Amateur Extra Class Study Guide

E1A01Why is it not legal to transmit a 3 kHz bandwidth USB signal with a carrier frequency of 14.348 MHz?

DThe upper 1 kHz of the signal is outside the 20-meter band

Tip20 m ends at 14.350. USB at 14.348 + 3 kHz = 14.351, so 1 kHz hangs outside the band.

E1A02When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

D3 kHz above the lower band edge

TipLSB extends BELOW the dial, so the dial must be at least 3 kHz above the bottom edge.

E1A03What is the highest legal carrier frequency on the 20-meter band for transmitting a 2.8 kHz wide USB data signal?

C14.1472 MHz

Tip20 m data ends at 14.150. 14.150 − 0.0028 = 14.1472 MHz.

E1A04May an Extra class operator answer the CQ of a station on 3.601 MHz LSB phone?

CNo, the sideband components will extend beyond the edge of the phone band segment

Tip80 m phone starts at 3.600. LSB on 3.601 spills below 3.600, so no.

E1A05Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

CAny person holding an FCC issued amateur license or who is authorized for alien reciprocal operation

TipOn a US vessel, anyone with an FCC license (or reciprocal authorization) can be in control.

E1A06What is the required transmit frequency of a CW signal for channelized 60 meter operation?

BAt the center frequency of the channel

Tip60 m CW goes at the CENTER of the channel.

E1A07What is the maximum power permitted on the 2200-meter band?

C1 watt EIRP (equivalent isotropic radiated power)

Tip2200 m = 1 W EIRP. 630 m = 5 W EIRP (E1A09). "Longer band, less power."

E1A08If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

BThe control operator of the originating station

TipForwarding a bad message? The ORIGINATING station's operator is accountable.

E1A09Except in some parts of Alaska, what is the maximum power permitted on the 630-meter band?

D5 watts EIRP (equivalent isotropic radiated power)

Tip630 m = 5 W EIRP (2200 m is 1 W).

E1A10If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

AIts operation must be approved by the master of the ship or the pilot in command of the aircraft

TipShip or plane: the captain or pilot must approve.

E1A11What licensing is required when operating an amateur station aboard a US-registered vessel in international waters?

BAny FCC-issued amateur license

TipInternational waters on a US ship: any FCC license.

E1B01Which of the following constitutes a spurious emission?

DAn emission outside the signal’s necessary bandwidth that can be reduced or eliminated without affecting the information transmitted

TipSpurious = outside the needed bandwidth and removable without hurting the information.

E1B02Which of the following is an acceptable bandwidth for digital voice or slow-scan TV transmissions made on the HF amateur bands?

A3 kHz

TipDigital voice or SSTV on HF: 3 kHz (same as SSB voice).

E1B03Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

A1 mile

TipProtect FCC monitoring stations within 1 mile.

E1B04What must the control operator of a repeater operating in the 70-centimeter band do if a radiolocation system experiences interference from that repeater?

CCease operation or make changes to the repeater that mitigate the interference

TipA 70 cm repeater bothering radiolocation (radar) must stop or fix it. Hams are secondary there.

E1B05What is the National Radio Quiet Zone?

CAn area surrounding the National Radio Astronomy Observatory

TipNational Radio Quiet Zone = around the radio astronomy observatory (Green Bank, WV).

E1B06Which of the following additional rules apply if you are erecting an amateur station antenna structure at a site at or near a public use airport?

AYou may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of the FCC rules

TipNear an airport: you may have to notify the FAA and register with the FCC (Part 17).

E1B07To what type of regulations does PRB-1 apply?

CState and local zoning

TipPRB-1 = state and LOCAL ZONING.

E1B08What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

DThe amateur station must avoid transmitting during certain hours on frequencies that cause the interference

TipInterfering with good-quality broadcast receivers: the FCC can impose quiet hours.

E1B09Which amateur stations may be operated under RACES rules?

CAny FCC-licensed amateur station certified by the responsible civil defense organization for the area served

TipRACES: any licensed station certified by civil defense.

E1B10What frequencies are authorized to an amateur station operating under RACES rules?

AAll amateur service frequencies authorized to the control operator

TipRACES: all frequencies the control operator is normally allowed.

E1B11What does PRB-1 require of state and local regulations affecting amateur radio antenna size and structures?

BReasonable accommodations of amateur radio must be made

TipPRB-1 = "reasonable accommodation."

E1C01What is the maximum bandwidth for a data emission on 60 meters?

D2.8 kHz

Tip60 m data max = 2.8 kHz.

E1C02Which of the following apply to communications transmitted to amateur stations in foreign countries?

CCommunications must be limited to those incidental to the purpose of the amateur service and remarks of a personal nature

TipForeign contacts: incidental to ham radio + personal remarks.

E1C03How long must an operator wait after filing a notification with the Utilities Technology Council (UTC) before operating on the 2200-meter or 630-meter band?

BOperators may operate after 30 days, providing they have not been told that their station is within 1 kilometer of PLC systems using those frequencies

Tip630/2200 m: wait 30 days after notifying the UTC (unless told you're within 1 km of power-line systems).

E1C04What is an IARP?

AA permit that allows US amateurs to operate in certain countries of the Americas

TipIARP = permit for the Americas (I-Am-in-the-Americas Radio Permit).

E1C05Under what situation may a station transmit third party communications while being automatically controlled?

BOnly when transmitting RTTY or data emissions

TipAutomatic third-party traffic: only RTTY or data.

E1C06Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

CYou must have a copy of FCC Public Notice DA 16-1048

TipCEPT abroad: carry a copy of FCC Public Notice DA 16-1048.

E1C07What notifications must be given before transmitting on the 630- or 2200-meter bands?

DOperators must inform the Utilities Technology Council (UTC) of their call sign and coordinates of the station

Tip630/2200 m: tell the UTC your call sign and coordinates.

E1C08What is the maximum permissible duration of a remotely controlled station’s transmissions if its control link malfunctions?

B3 minutes

TipRemote control link fails: off the air within 3 minutes.

E1C09What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

B1.0

TipFM/PM below 29 MHz: modulation index max 1.0.

E1C10What is the maximum mean power level for a spurious emission below 30 MHz with respect to the fundamental emission?

A- 43 dB

TipSpurious below 30 MHz: −43 dB.

E1C11Which of the following operating arrangements allows an FCC-licensed US citizen to operate in many European countries, and amateurs from many European countries to operate in the US?

ACEPT

TipEurope reciprocal = CEPT.

E1C12In what portion of the 630-meter band are phone emissions permitted?

DThe entire band

TipPhone on 630 m: the entire band.

E1D01What is the definition of telemetry?

AOne-way transmission of measurements at a distance from the measuring instrument

TipTelemetry = one-way measurements sent from far away.

E1D02Which of the following may transmit encrypted messages?

BTelecommand signals from a space telecommand station

TipEncryption allowed only for space telecommand.

E1D03What is a space telecommand station?

BAn amateur station that transmits communications to initiate, modify, or terminate functions of a space station

TipTelecommand = commands that control a space station.

E1D04Which of the following is required in the identification transmissions from a balloon-borne telemetry station?

ACall sign

TipBalloon telemetry must ID with a call sign.

E1D05What must be posted at the location of a station being operated by telecommand on or within 50 kilometers of the Earth’s surface?

DAll these choices are correct

TipTelecommand station: post name, address, phone... "All these."

E1D06What is the maximum permitted transmitter output power when operating a model craft by telecommand?

A1 watt

TipModel craft telecommand: 1 W max.

E1D07Which of the following HF amateur bands include allocations for space stations?

A40 meters, 20 meters, 15 meters, and 10 meters

TipHF space station bands: 40, 20, 15, 10 m.

E1D08Which VHF amateur bands have frequencies authorized for space stations?

D2 meters

TipVHF space: 2 m.

E1D09Which UHF amateur bands have frequencies authorized for space stations?

B70 centimeters and 13 centimeters

TipUHF space: 70 cm and 13 cm.

E1D10Which amateur stations are eligible to be telecommand stations of space stations, subject to the privileges of the class of operator license held by the control operator of the station?

BAny amateur station so designated by the space station licensee

TipTelecommand stations: whoever the space station licensee designates.

E1D11Which amateur stations are eligible to operate as Earth stations?

DAny amateur station, subject to the privileges of the class of operator license held by the control operator

TipEarth stations: any amateur station.

E1D12Which of the following amateur stations may transmit one-way communications?

AA space station, beacon station, or telecommand station

TipOne-way allowed: space station, beacon, telecommand.

E1E01For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

APreparing, processing, administering, and coordinating an examination for an amateur radio operator license

TipVEs can be reimbursed for exam expenses (preparing, administering, and so on).

E1E02Who is tasked by Part 97 with maintaining the pools of questions for all US amateur license examinations?

CThe VECs

TipThe VECs maintain the question pools.

E1E03What is a Volunteer Examiner Coordinator?

CAn organization that has entered into an agreement with the FCC to coordinate, prepare, and administer amateur operator license examinations

TipVEC = an organization with an FCC agreement to coordinate exams.

E1E04What is required to be accredited as a Volunteer Examiner?

DA VEC must confirm that the VE applicant meets FCC requirements to serve as an examiner

TipA VEC accredits the VE.

E1E05What must the VE team do with the application form if the examinee does not pass the exam?

BReturn the application document to the examinee

TipFailed? Hand the application back to the examinee.

E1E06Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

CEach administering VE

TipEACH VE is responsible for the session.

E1E07What should a VE do if a candidate fails to comply with the examiner’s instructions during an amateur operator license examination?

BImmediately terminate the candidate’s examination

TipCandidate won't follow instructions: end their exam immediately.

E1E08To which of the following examinees may a VE not administer an examination?

CRelatives of the VE as listed in the FCC rules

TipA VE can't test their own relatives.

E1E09What may be the penalty for a VE who fraudulently administers or certifies an examination?

ARevocation of the VE’s amateur station license grant and the suspension of the VE’s amateur operator license grant

TipFraudulent VE: station license revoked + operator license suspended.

E1E10What must the administering VEs do after the administration of a successful examination for an amateur operator license?

CThey must submit the application document to the coordinating VEC according to the coordinating VEC instructions

TipPassed: send the application to the VEC.

E1E11What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

BThree VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements

TipPassed: three VEs certify.

E1F01On what frequencies are spread spectrum transmissions permitted?

BOnly on amateur frequencies above 222 MHz

TipSpread spectrum only above 222 MHz.

E1F02What privileges are authorized in the US to persons holding an amateur service license granted by the government of Canada?

CThe operating terms and conditions of the Canadian amateur service license, not to exceed US Amateur Extra class license privileges

TipCanadians in the US: their Canadian privileges, capped at Extra.

E1F03Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

DThe amplifier is constructed or modified by an amateur radio operator for use at an amateur station

TipUncertified amps can be sold if built or modified by a ham for ham use.

E1F04Which of the following geographic descriptions approximately describes "Line A"?

AA line roughly parallel to and south of the border between the US and Canada

TipLine A = runs just south of the US–Canada border.

E1F05Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

D420 MHz - 430 MHz

TipNorth of Line A: no 420–430 MHz.

E1F06Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

ATo provide for experimental amateur communications

TipSTA = Special Temporary Authority for experiments.

E1F07When may an amateur station send a message to a business?

DWhen neither the amateur nor their employer has a pecuniary interest in the communications

TipMessages to a business: OK only if neither the ham nor their employer profits.

E1F08Which of the following types of amateur station communications are prohibited?

ACommunications transmitted for hire or material compensation, except as otherwise provided in the rules

TipHire or compensation = prohibited.

E1F09Which of the following cannot be transmitted over an amateur radio mesh network?

CMessages encoded to obscure their meaning

TipMesh network: no encrypted messages.

E1F10Who may be the control operator of an auxiliary station?

BOnly Technician, General, Advanced, or Amateur Extra class operators

TipAuxiliary control op: Technician or higher.

E1F11Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

DIt must satisfy the FCC’s spurious emission standards when operated at the lesser of 1500 watts or its full output power

TipAmp certification: must meet spurious limits at 1500 W or full output (whichever is less).

E2A01What is the direction of an ascending pass for an amateur satellite?

CFrom south to north

TipAscending pass = moving south to north.

E2A02Which of the following is characteristic of an inverting linear transponder?

DAll these choices are correct

TipInverting transponder questions: "All these."

E2A03How is an upload signal processed by an inverting linear transponder?

DThe signal is mixed with a local oscillator signal and the difference product is transmitted

TipInverting transponder transmits the DIFFERENCE product (that's what flips it).

E2A04What is meant by the “mode” of an amateur radio satellite?

BThe satellite’s uplink and downlink frequency bands

TipSatellite "mode" = its uplink and downlink bands.

E2A05What do the letters in a satellite’s mode designator specify?

DThe uplink and downlink frequency ranges

TipMode letters = uplink and downlink frequency ranges.

E2A06What are Keplerian elements?

AParameters that define the orbit of a satellite

TipKeplerian elements = orbit parameters.

E2A07Which of the following types of signals can be relayed through a linear transponder?

DAll these choices are correct

TipLinear transponders relay SSB, CW, data: "All these."

E2A08Why should effective radiated power (ERP) be limited to a satellite that uses a linear transponder?

BTo avoid reducing the downlink power to all other users

TipToo much uplink power steals downlink power from everyone else.

E2A09What do the terms “L band” and “S band” specify?

AThe 23- and 13-centimeter bands

TipL band = 23 cm, S band = 13 cm.

E2A10What type of satellite appears to stay in one position in the sky?

BGeostationary

TipStays in one spot = geostationary.

E2A11What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

BA circularly polarized antenna

TipSpin and Faraday fading = circular polarization.

E2A12What is the purpose of digital store-and-forward functions on an amateur radio satellite?

CTo hold digital messages in the satellite for later download

TipStore-and-forward = holds messages for later download.

E2B01In digital television, what does a coding rate of 3/4 mean?

A25% of the data sent is forward error correction data

TipCoding rate 3/4 = 3/4 data, 1/4 (25%) error correction.

E2B02How many horizontal lines make up a fast-scan (NTSC) television frame?

C525

TipNTSC = 525 lines.

E2B03How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?

DBy scanning odd-numbered lines in one field and even-numbered lines in the next

TipInterlaced = odd lines, then even lines.

E2B04How is color information sent in analog SSTV?

AColor lines are sent sequentially

TipAnalog SSTV color = lines sent one after another.

E2B05Which of the following describes the use of vestigial sideband in analog fast-scan TV transmissions?

CVestigial sideband reduces the bandwidth while increasing the fidelity of low frequency video components

TipVestigial sideband = less bandwidth, better low-frequency video.

E2B06What is vestigial sideband modulation?

AAmplitude modulation in which one complete sideband and a portion of the other are transmitted

TipVSB = one full sideband + a "vestige" (part) of the other.

E2B07Which types of modulation are used for amateur television DVB-T signals?

BQAM and QPSK

TipDVB-T = QAM and QPSK.

E2B08What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70-centimeter band?

ATransmitting on channels shared with cable TV

Tip70 cm FSTV on a TV set: use the channels shared with cable TV.

E2B09What kind of receiver can be used to receive and decode SSTV using the Digital Radio Mondiale (DRM) protocol?

DSSB

TipDRM SSTV = an SSB receiver.

E2B10What aspect of an analog slow-scan television signal encodes the brightness of the picture?

ATone frequency

TipSSTV brightness = tone frequency.

E2B11What is the function of the vertical interval signaling (VIS) code sent as part of an SSTV transmission?

BTo identify the SSTV mode being used

TipVIS code = identifies the SSTV mode.

E2B12What signals SSTV receiving software to begin a new picture line?

ASpecific tone frequencies

TipNew line = specific tone (sync tone).

E2C01What indicator is required to be used by US-licensed operators when operating a station via remote control and the remote transmitter is located in the US?

DNo additional indicator is required

TipRemote operation with the transmitter in the US: no extra indicator.

E2C02Which of the following file formats is used for exchanging amateur radio log data?

CADIF

TipLog file format = ADIF.

E2C03From which of the following bands is amateur radio contesting generally excluded?

A30 meters

TipNo contesting on 30 m (WARC bands).

E2C04Which of the following frequencies can be used for amateur radio mesh networks?

BFrequencies shared with various unlicensed wireless data services

TipMesh = shared with unlicensed Wi-Fi.

E2C05What is the function of a DX QSL Manager?

BHandle the receiving and sending of confirmations for a DX station

TipDX QSL manager handles confirmations for a DX station.

E2C06During a VHF/UHF contest, in which band segment would you expect to find the highest level of SSB or CW activity?

CIn the weak signal segment of the band, with most of the activity near the calling frequency

TipVHF/UHF contests: weak-signal segment, near the calling frequency.

E2C07What is the Cabrillo format?

AA standard for submission of electronic contest logs

TipCabrillo = contest log submission format.

E2C08Which of the following contacts may be confirmed through the Logbook of The World (LoTW)?

DAll these choices are correct

TipLoTW confirms all kinds of contacts: "All these."

E2C09What type of equipment is commonly used to implement an amateur radio mesh network?

CA wireless router running custom firmware

TipMesh gear = a Wi-Fi router with custom firmware.

E2C10Why do DX stations often transmit and receive on different frequencies?

DAll these choices are correct

TipDX works "split" to avoid pileups, interference, and different band rules: "All these."

E2C11How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

ASend your full call sign once or twice

TipPileup: send your FULL call once or twice.

E2C12What indicates the delay between a control operator action and the corresponding change in the transmitted signal?

CLatency

TipDelay = LATENCY.

E2D01Which of the following digital modes is designed for meteor scatter communications?

BMSK144

TipMeteor scatter = MSK144 ("M" for Meteor).

E2D02What information replaces signal-to-noise ratio when using the FT8 or FT4 modes in a VHF contest?

DGrid square

TipVHF contest FT8/FT4: send the grid square instead of a signal report.

E2D03Which of the following digital modes is designed for EME communications?

DQ65

TipEME (moonbounce) = Q65.

E2D04What technology is used for real-time tracking of balloons carrying amateur radio transmitters?

CAPRS

TipBalloon tracking = APRS.

E2D05What is the characteristic of the JT65 mode?

BDecodes signals with a very low signal-to-noise ratio

TipJT65 = very weak signals.

E2D06Which of the following is a method for establishing EME contacts?

ATime-synchronous transmissions alternating between stations

TipEME: stations take turns in timed slots.

E2D07What digital protocol is used by APRS?

CAX.25

TipAPRS runs on AX.25 (packet).

E2D08What type of packet frame is used to transmit APRS beacon data?

CUnnumbered Information

TipAPRS beacon = Unnumbered Information (UI) frame.

E2D09What type of modulation is used by JT65?

AMultitone AFSK

TipJT65 = multitone AFSK (65 tones).

E2D10What does the packet path WIDE3-1 designate?

CThree digipeater hops are requested with one remaining

TipWIDE3-1 = 3 hops requested, 1 left.

E2D11How do APRS stations relay data?

DBy packet digipeaters

TipAPRS relays via packet digipeaters.

E2E01Which of the following types of modulation is used for data emissions below 30 MHz?

BFSK

TipHF data = FSK.

E2E02Which of the following synchronizes WSJT-X digital mode transmit/receive timing?

BSynchronization of computer clocks

TipWSJT-X timing = synchronized computer clocks.

E2E03To what does the "4" in FT4 refer?

BFour-tone continuous-phase frequency shift keying

TipFT4 = four-tone FSK.

E2E04Which of the following is characteristic of the FST4 mode?

DAll these choices are correct

TipFST4 questions: "All these."

E2E05Which of these digital modes does not support keyboard-to-keyboard operation?

AWSPR

TipWSPR is beacon-only, not keyboard chat.

E2E06What is the length of an FT8 transmission cycle?

C15 seconds

TipFT8 cycle = 15 seconds.

E2E07How does Q65 differ from JT65?

CMultiple receive cycles are averaged

TipQ65 averages several receive cycles.

E2E08Which of the following HF digital modes can be used to transfer binary files?

BPACTOR

TipBinary files over HF = PACTOR.

E2E09Which of the following HF digital modes uses variable-length character coding?

DPSK31

TipVariable-length code = PSK31 (Varicode).

E2E10Which of these digital modes has the narrowest bandwidth?

CFT8

TipNarrowest = FT8 (about 50 Hz).

E2E11What is the difference between direct FSK and audio FSK?

ADirect FSK modulates the transmitter VFO

TipDirect FSK shifts the VFO itself (audio FSK uses tones).

E2E12How do ALE stations establish contact?

AALE constantly scans a list of frequencies, activating the radio when the designated call sign is received

TipALE scans frequencies and wakes up when its call sign is received.

E2E13Which of these digital modes has the highest data throughput under clear communication conditions?

DPACTOR IV

TipFastest = PACTOR IV.

E3A01What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by EME?

D12,000 miles, if the moon is “visible” by both stations

TipEME reaches 12,000 miles: anywhere both stations can see the moon.

E3A02What characterizes libration fading of an EME signal?

BA fluttery, irregular fading

TipLibration fading = fluttery, irregular (the moon wobbles).

E3A03When scheduling EME contacts, which of these conditions will generally result in the least path loss?

AWhen the Moon is at perigee

TipLeast EME loss at perigee (moon closest).

E3A04In what direction does an electromagnetic wave travel?

DIt travels at a right angle to the electric and magnetic fields

TipThe wave travels at right angles to both fields.

E3A05How are the component fields of an electromagnetic wave oriented?

CThey are at right angles

TipElectric and magnetic fields are at right angles.

E3A06What should be done to continue a long-distance contact when the MUF for that path decreases due to darkness?

BSwitch to a lower frequency HF band

TipMUF dropping at night: go to a LOWER band.

E3A07Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

CLarge bodies of water

TipMicrowave ducts form over large bodies of water.

E3A08When a meteor strikes the Earth’s atmosphere, a linear ionized region is formed at what region of the ionosphere?

AThe E region

TipMeteor trails form in the E region.

E3A09Which of the following frequency ranges is most suited for meteor-scatter communications?

C28 MHz - 148 MHz

TipMeteor scatter: 28–148 MHz (6 m is best).

E3A10What determines the speed of electromagnetic waves through a medium?

DThe index of refraction

TipSpeed in a medium = index of refraction.

E3A11What is a typical range for tropospheric duct propagation of microwave signals?

B100 miles to 300 miles

TipTropo duct range: 100–300 miles.

E3A12What is most likely to result in auroral propagation?

CSevere geomagnetic storms

TipAurora = severe geomagnetic storms.

E3A13Which of these emission modes is best for auroral propagation?

ACW

TipAurora: CW (it survives the distortion).

E3A14What are circularly polarized electromagnetic waves?

BWaves with rotating electric and magnetic fields

TipCircular polarization = rotating fields.

E3B01Where is transequatorial propagation (TEP) most likely to occur?

ABetween points separated by 2,000 miles to 3,000 miles over a path perpendicular to the geomagnetic equator

TipTEP: 2,000–3,000 miles straight across the geomagnetic equator.

E3B02What is the approximate maximum range for signals using transequatorial propagation?

C5,000 miles

TipTEP max range ≈ 5,000 miles.

E3B03At what time of day is transequatorial propagation most likely to occur?

CAfternoon or early evening

TipTEP: afternoon or early evening.

E3B04What are “extraordinary” and “ordinary” waves?

BIndependently propagating, elliptically polarized waves created in the ionosphere

TipOrdinary and extraordinary waves = elliptically polarized waves created in the ionosphere.

E3B05Which of the following paths is most likely to support long-distance propagation on 160 meters?

DA path entirely in darkness

Tip160 m DX: a path entirely in darkness.

E3B06On which of the following amateur bands is long-path propagation most frequent?

B40 meters and 20 meters

TipLong-path: most often on 40 m and 20 m.

E3B07What effect does lowering a signal’s transmitted elevation angle have on ionospheric HF skip propagation?

CThe distance covered by each hop increases

TipLower angle = longer hops.

E3B08How does the maximum range of ground-wave propagation change when the signal frequency is increased?

CIt decreases

TipHigher frequency = shorter ground-wave range.

E3B09At what time of year is sporadic-E propagation most likely to occur?

AAround the solstices, especially the summer solstice

TipSporadic E: around the solstices, especially summer.

E3B10What is the effect of chordal-hop propagation?

AThe signal experiences less loss compared to multi-hop propagation, which uses Earth as a reflector

TipChordal hop = less loss (no ground bounce in between).

E3B11At what time of day is sporadic-E propagation most likely to occur?

DBetween sunrise and sunset

TipSporadic E: daytime (sunrise to sunset).

E3B12What is chordal-hop propagation?

BSuccessive ionospheric refractions without an intermediate reflection from the ground

TipChordal hop = bounces between ionosphere layers, skipping the ground.

E3B13What type of polarization is supported by ground-wave propagation?

AVertical

TipGround wave = vertical polarization.

E3C01What is the cause of short-term radio blackouts?

DSolar flares

TipShort blackouts = solar flares.

E3C02What is indicated by a rising A-index or K-index?

AIncreasing disturbance of the geomagnetic field

TipRising A or K index = more disturbed.

E3C03Which of the following signal paths is most likely to experience high levels of absorption when the A-index or K-index is elevated?

BThrough the auroral oval

TipHigh A/K: paths through the auroral oval get absorbed.

E3C04What does the value of Bz (B sub z) represent?

CNorth-south strength of the interplanetary magnetic field

TipBz = north-south component of the sun's magnetic field.

E3C05What orientation of Bz (B sub z) increases the likelihood that charged particles from the Sun will cause disturbed conditions?

ASouthward

TipBz SOUTH = trouble ("South = Storm").

E3C06How does the VHF/UHF radio horizon compare to the geographic horizon?

AIt is approximately 15 percent farther

TipRadio horizon ≈ 15% farther than the visual horizon.

E3C07Which of the following indicates the greatest solar flare intensity?

DClass X

TipStrongest flare = Class X ("X = eXtreme").

E3C08Which of the following is the space-weather term for an extreme geomagnetic storm?

DG5

TipExtreme storm = G5 (top of the G1–G5 scale).

E3C09What type of data is reported by amateur radio propagation reporting networks?

DDigital-mode and CW signals

TipPropagation networks report digital and CW signals (RBN, PSK Reporter).

E3C10What does the 304A solar parameter measure?

BUV emissions at 304 angstroms, correlated to the solar flux index

Tip304A = UV at 304 angstroms (tracks solar flux).

E3C11What does VOACAP software model?

CHF propagation

TipVOACAP = HF propagation modeling.

E3C12Which of the following is indicated by a sudden rise in radio background noise across a large portion of the HF spectrum?

BA coronal mass ejection impact or a solar flare has occurred

TipNoise jumps across HF: flare or CME hit.

E4A01Which of the following limits the highest frequency signal that can be accurately displayed on a digital oscilloscope?

ASampling rate of the analog-to-digital converter

TipDigital scope frequency limit = ADC sampling rate.

E4A02Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

BSignal amplitude and frequency

TipSpectrum analyzer: amplitude (vertical) vs frequency (horizontal).

E4A03Which of the following test instruments is used to display spurious signals and/or intermodulation distortion products generated by an SSB transmitter?

BSpectrum analyzer

TipSpurs and IMD = spectrum analyzer.

E4A04How is compensation of an oscilloscope probe performed?

AA square wave is displayed, and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible

TipProbe compensation: adjust until the square wave tops are flat.

E4A05What is the purpose of using a prescaler with a frequency counter?

DReduce the signal frequency to within the counter's operating range

TipPrescaler divides the frequency down to the counter's range.

E4A06What is the effect of aliasing on a digital oscilloscope when displaying a waveform?

AA false, jittery low-frequency version of the waveform is displayed

TipAliasing = a fake low-frequency jittery wave.

E4A07Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge?

BAntenna analyzers compute SWR and impedance automatically

TipAn analyzer calculates SWR and impedance for you.

E4A08Which of the following is used to measure SWR?

DAll these choices are correct

TipSWR measuring tools: "All these."

E4A09Which of the following is good practice when using an oscilloscope probe?

AMinimize the length of the probe's ground connection

TipKeep the probe's ground lead SHORT.

E4A10Which trigger mode is most effective when using an oscilloscope to measure a linear power supply’s output ripple?

DLine

TipMeasuring power supply ripple = trigger on "Line."

E4A11Which of the following can be measured with an antenna analyzer?

DAll these choices are correct

TipAntenna analyzer measures many things: "All these."

E4B01Which of the following factors most affects the accuracy of a frequency counter?

BTime base accuracy

TipCounter accuracy = time base accuracy.

E4B02What is the significance of voltmeter sensitivity expressed in ohms per volt?

AThe full scale reading of the voltmeter multiplied by its ohms per volt rating is the input impedance of the voltmeter

TipFull scale × ohms-per-volt = input impedance.

E4B03Which S parameter is equivalent to forward gain?

CS21

TipForward gain = S21 ("2 from 1": out port 2, in port 1).

E4B04Which S parameter represents input port return loss or reflection coefficient (equivalent to VSWR)?

AS11

TipInput reflection = S11 (in and back to the same port).

E4B05What three test loads are used to calibrate an RF vector network analyzer?

BShort circuit, open circuit, and 50 ohms

TipVNA calibration: short, open, 50 Ω load.

E4B06How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

D75 watts

Tip100 forward − 25 reflected = 75 W absorbed.

E4B07What do the subscripts of S parameters represent?

AThe port or ports at which measurements are made

TipS-parameter subscripts = the ports.

E4B08Which of the following can be used to determine the Q of a series-tuned circuit?

CThe bandwidth of the circuit's frequency response

TipQ from bandwidth (Q = f ÷ BW).

E4B09Which of the following can be measured by a two-port vector network analyzer?

BFilter frequency response

TipTwo-port VNA = filter response.

E4B10Which of the following methods measures intermodulation distortion in an SSB transmitter?

BModulate the transmitter using two AF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer

TipIMD test = two non-harmonic audio tones + spectrum analyzer.

E4B11Which of the following can be measured with a vector network analyzer?

DAll these choices are correct

TipVNA measures many things: "All these."

E4C01What is an effect of excessive phase noise in an SDR receiver’s master clock oscillator?

DIt can combine with strong signals on nearby frequencies to generate interference

TipClock phase noise mixes with nearby strong signals and causes interference.

E4C02Which of the following receiver circuits can be effective in eliminating interference from strong out-of-band signals?

AA front-end filter or preselector

TipStrong out-of-band signals = front-end filter or preselector.

E4C03What is the term for the suppression in an FM receiver of one signal by another stronger signal on the same frequency?

CCapture effect

TipStronger FM signal wins = capture effect.

E4C04What is the noise figure of a receiver?

DThe ratio in dB of the noise generated by the receiver to the theoretical minimum noise

TipNoise figure = receiver noise vs the theoretical minimum, in dB.

E4C05What does a receiver noise floor of -174 dBm represent?

BThe theoretical noise in a 1 Hz bandwidth at the input of a perfect receiver at room temperature

Tip−174 dBm = theoretical noise of a perfect receiver in 1 Hz at room temperature.

E4C06How much does increasing a receiver’s bandwidth from 50 Hz to 1,000 Hz increase the receiver’s noise floor?

D13 dB

Tip50 → 1000 Hz = 20× wider. 10 log(20) ≈ 13 dB.

E4C07What does the MDS of a receiver represent?

BThe minimum discernible signal

TipMDS = Minimum Discernible Signal.

E4C08An SDR receiver is overloaded when input signals exceed what level?

DThe reference voltage of the analog-to-digital converter

TipSDR overload = input exceeds the ADC reference voltage.

E4C09Which of the following choices is a good reason for selecting a high IF for a superheterodyne HF or VHF communications receiver?

CEasier for front-end circuitry to eliminate image responses

TipHigh IF = images are easier to reject.

E4C10What is an advantage of having a variety of receiver bandwidths from which to select?

CReceive bandwidth can be set to match the modulation bandwidth, maximizing signal-to-noise ratio and minimizing interference

TipMatch bandwidth to the mode for the best S/N.

E4C11Why does input attenuation reduce receiver overload on the lower frequency HF bands with little or no impact on signal-to-noise ratio?

DAtmospheric noise is generally greater than internally generated noise even after attenuation

TipOn low bands, atmospheric noise dominates anyway, so attenuating doesn't hurt S/N.

E4C12How does a narrow-band roofing filter affect receiver performance?

CIt improves blocking dynamic range by attenuating strong signals near the receive frequency

TipRoofing filter = narrow filter up front that improves blocking dynamic range.

E4C13What is reciprocal mixing?

DLocal oscillator phase noise mixing with adjacent strong signals to create interference to desired signals

TipReciprocal mixing = LO phase noise mixing with strong nearby signals.

E4C14What is the purpose of the receiver IF Shift control?

CTo reduce interference from stations transmitting on adjacent frequencies

TipIF Shift = slide the passband away from adjacent interference.

E4D01What is meant by the blocking dynamic range of a receiver?

AThe difference in dB between the noise floor and the level of an incoming signal that will cause 1 dB of gain compression

TipBlocking dynamic range = noise floor up to the signal level that causes 1 dB of compression.

E4D02Which of the following describes problems caused by poor dynamic range in a receiver?

ASpurious signals caused by cross modulation and desensitization from strong adjacent signals

TipPoor dynamic range = cross-modulation and desensitization.

E4D03What creates intermodulation interference between two repeaters in close proximity?

BThe output signals mix in the final amplifier of one or both transmitters

TipRepeater intermod = the two outputs mixing in a transmitter's final amplifier.

E4D04Which of the following is used to reduce or eliminate intermodulation interference in a repeater caused by a nearby transmitter?

BA properly terminated circulator at the output of the repeater’s transmitter

TipRepeater intermod fix = a circulator on the transmitter output.

E4D06What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

CDesensitization

TipStrong nearby signal reducing sensitivity = DESENSITIZATION.

E4D07Which of the following reduces the likelihood of receiver desensitization?

AInsert attenuation before the first RF stage

TipPrevent desense: add attenuation before the first RF stage.

E4D08What causes intermodulation in an electronic circuit?

CNonlinear circuits or devices

TipIntermod comes from NONLINEAR circuits.

E4D09What is the purpose of the preselector in a communications receiver?

CTo increase the rejection of signals outside the band being received

TipPreselector = rejects signals outside the band.

E4D10What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

CA pair of 40 dBm input signals will theoretically generate a third-order intermodulation product that has the same output amplitude as either of the input signals

TipIP3 of 40 dBm = two 40 dBm inputs would create a 3rd-order product as strong as the inputs (theoretical).

E4D11Why are odd-order intermodulation products, created within a receiver, of particular interest compared to other products?

AOdd-order products of two signals in the band being received are also likely to be within the band

TipOdd-order products fall inside your band, so they matter most.

E4D12What is the link margin in a system with a transmit power level of 10 W (+40 dBm), a system antenna gain of 10 dBi, a cable loss of 3 dB, a path loss of 136 dB, a receiver minimum discernable signal of -103 dBm, and a required signal-to-noise ratio of 6 dB?

C+8dB

TipReceived: 40 + 10 − 3 − 136 = −89 dBm. Needed: −103 + 6 = −97 dBm. Margin = +8 dB.

E4D13What is the received signal level with a transmit power of 10 W (+40 dBm), a transmit antenna gain of 6 dBi, a receive antenna gain of 3 dBi, and a path loss of 100 dB?

A-51 dBm

Tip40 + 6 + 3 − 100 = −51 dBm.

E4D14What power level does a receiver minimum discernible signal of -100 dBm represent?

D0.1 picowatts

Tip−100 dBm = 10⁻¹³ W = 0.1 picowatts.

E4E01What problem can occur when using an automatic notch filter (ANF) to remove interfering carriers while receiving CW signals?

ARemoval of the CW signal as well as the interfering carrier

TipAn auto-notch can remove the CW signal too (CW looks like a carrier).

E4E02Which of the following types of noise can often be reduced by a digital noise reduction?

DAll these choices are correct

TipDSP noise reduction works on many noise types: "All these."

E4E03Which of the following types of noise are removed by a noise blanker?

BImpulse noise

TipNoise blanker = impulse noise (pops and clicks).

E4E04How can conducted noise from an automobile battery charging system be suppressed?

DBy installing ferrite chokes on the charging system leads

TipCar charging noise: ferrite chokes on the charging leads.

E4E05What is used to suppress radio frequency interference from a line-driven AC motor?

BA brute-force AC-line filter in series with the motor’s power leads

TipAC motor noise: brute-force AC line filter.

E4E06What type of electrical interference can be caused by computer network equipment?

CThe appearance of unstable modulated or unmodulated signals at specific frequencies

TipNetwork gear = unstable signals at specific frequencies (birdies).

E4E07Which of the following can cause shielded cables to radiate or receive interference?

BCommon-mode currents on the shield and conductors

TipShielded cable radiates from common-mode current.

E4E08What current flows equally on all conductors of an unshielded multiconductor cable?

BCommon-mode current

TipSame current on all conductors = common-mode.

E4E09What undesirable effect can occur when using a noise blanker?

CStrong signals may be distorted and appear to cause spurious emissions

TipNoise blanker side effect: strong signals get distorted.

E4E10Which of the following can create intermittent loud roaring or buzzing AC line interference?

DAll these choices are correct

TipRoaring or buzzing AC-line noise: many causes (arcing, bad insulators...). "All these."

E4E11What could be the cause of local AM broadcast band signals combining to generate spurious signals on the MF or HF bands?

BNearby corroded metal connections are mixing and reradiating the broadcast signals

TipAM broadcast mixing = corroded metal joints acting like diodes ("rusty bolt").

E4E12What causes interference received as a series of carriers at regular intervals across a wide frequency range?

ASwitch-mode power supplies

TipCarriers at regular intervals = switch-mode power supplies.

E4E13Where should a station AC surge protector be installed?

COn the single point ground panel

TipAC surge protector goes on the single-point ground panel.

E4E14What is the purpose of a single point ground panel?

DEnsure all lightning protectors activate at the same time

TipSingle-point ground = all protectors trip together.

E5A01What can cause the voltage across reactances in a series RLC circuit to be higher than the voltage applied to the entire circuit?

AResonance

TipResonance makes reactance voltages higher than the applied voltage.

E5A02What is the resonant frequency of an RLC circuit if R is 22 ohms, L is 50 microhenries, and C is 40 picofarads?

C3.56 MHz

Tipf = 1/(2π√LC) = 1/(2π√(50µH × 40pF)) ≈ 3.56 MHz. (R doesn't matter.)

E5A03What is the magnitude of the impedance of a series RLC circuit at resonance?

DApproximately equal to circuit resistance

TipSeries resonance: Z ≈ R.

E5A04What is the magnitude of the impedance of a parallel RLC circuit at resonance?

AApproximately equal to circuit resistance

TipParallel resonance: Z ≈ R too.

E5A05What is the result of increasing the Q of an impedance-matching circuit?

AMatching bandwidth is decreased

TipHigher Q = narrower bandwidth.

E5A06What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

BIt is at a maximum

TipParallel LC at resonance: circulating current is MAXIMUM.

E5A07What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

AMinimum

TipParallel at resonance: input current is MINIMUM (impedance is highest).

E5A08What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

CThe voltage and current are in phase

TipAt resonance, V and I are in phase.

E5A09How is the Q of an RLC parallel resonant circuit calculated?

CResistance divided by the reactance of either the inductance or capacitance

TipParallel Q = R ÷ X (series is the opposite, X ÷ R).

E5A10What is the resonant frequency of an RLC circuit if R is 33 ohms, L is 50 microhenries, and C is 10 picofarads?

A7.12 MHz

Tipf = 1/(2π√(50µH × 10pF)) ≈ 7.12 MHz.

E5A11What is the half-power bandwidth of a resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

C47.3 kHz

TipBandwidth = f ÷ Q = 7.1 MHz ÷ 150 = 47.3 kHz.

E5A12What is the half-power bandwidth of a resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

C31.4 kHz

Tip3.7 MHz ÷ 118 = 31.4 kHz.

E5A13What is an effect of increasing Q in a series resonant circuit?

CInternal voltages increase

TipHigher Q in series = higher internal voltages.

E5B01What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage or to discharge to 36.8% of its initial voltage?

BOne time constant

Tip63.2% charge = one time constant.

E5B02What letter is commonly used to represent susceptance?

DB

TipSusceptance = B.

E5B03How is impedance in polar form converted to an equivalent admittance?

BTake the reciprocal of the magnitude and change the sign of the angle

TipZ → Y: take 1/magnitude and flip the angle's sign.

E5B04What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors, all in parallel?

D220 seconds

TipTwo 220 µF in parallel = 440 µF. Two 1 MΩ in parallel = 0.5 MΩ. 440µ × 0.5M = 220 s.

E5B05What is the effect on the magnitude of pure reactance when it is converted to susceptance?

DIt is replaced by its reciprocal

TipReactance → susceptance: take the reciprocal.

E5B06What is susceptance?

CThe imaginary part of admittance

TipSusceptance = the imaginary part of admittance.

E5B07What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

C14.0 degrees with the voltage lagging the current

TipX = 250 − 500 = −250 (capacitive). atan(250/1000) = 14°. Capacitive = voltage LAGS.

E5B08What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 300 ohms, R is 100 ohms, and XL is 100 ohms?

A63 degrees with the voltage lagging the current

TipX = 100 − 300 = −200. atan(200/100) = 63°. Capacitive = voltage lags.

E5B09What is the relationship between the AC current through a capacitor and the voltage across a capacitor?

DCurrent leads voltage by 90 degrees

TipICE: in a Capacitor, current (I) leads voltage (E) by 90°. "ELI the ICE man."

E5B10What is the relationship between the AC current through an inductor and the voltage across an inductor?

AVoltage leads current by 90 degrees

TipELI: in an inductor (L), voltage (E) leads current (I) by 90°.

E5B11What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 75 ohms?

B27 degrees with the voltage leading the current

TipX = 75 − 25 = +50 (inductive). atan(50/100) = 27°. Inductive = voltage LEADS.

E5B12What is admittance?

AThe inverse of impedance

TipAdmittance = 1/impedance.

E5C01Which of the following represents pure capacitive reactance of 100 ohms in rectangular notation?

A0 - j100

TipCapacitive = negative j: 0 − j100.

E5C02How are impedances described in polar coordinates?

CBy magnitude and phase angle

TipPolar = magnitude + angle.

E5C03Which of the following represents a pure inductive reactance in polar coordinates?

CA positive 90 degree phase angle

TipPure inductor = +90°.

E5C04What type of Y-axis scale is most often used for graphs of circuit frequency response?

DLogarithmic

TipFrequency response graphs use a log scale.

E5C05What kind of diagram is used to show the phase relationship between impedances at a given frequency?

CPhasor diagram

TipPhase relationships = phasor diagram.

E5C06What does the impedance 50 - j25 ohms represent?

B50 ohms resistance in series with 25 ohms capacitive reactance

Tip−j = capacitive: 50 Ω + 25 Ω capacitive.

E5C07Where is the impedance of a pure resistance plotted on rectangular coordinates?

DOn the horizontal axis

TipPure resistance = horizontal axis.

E5C08What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive, and/or capacitive reactance?

DPolar coordinates

TipPhase angles = polar coordinates.

E5C09When using rectangular coordinates to graph the impedance of a circuit, what do the axes represent?

AThe X axis represents the resistive component, and the Y axis represents the reactive component

TipRectangular: X axis = resistance, Y axis = reactance.

E5C10Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 400-ohm resistor and a 38-picofarad capacitor at 14 MHz?

BPoint 4

TipXc = 1/(2π × 14 MHz × 38 pF) ≈ 300 Ω, so 400 − j300 = Point 4. (Figure: Point 1 = 300 − j400, 3 = 300 + j400, 4 = 400 − j300.)

E5C11Which point in Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and an 18-microhenry inductor at 3.505 MHz?

BPoint 3

TipXL = 2π × 3.505 MHz × 18 µH ≈ 400 Ω, so 300 + j400 = Point 3 (above the axis).

E5C12Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz?

APoint 1

TipXc = 1/(2π × 21.2 MHz × 19 pF) ≈ 400 Ω, so 300 − j400 = Point 1.

E5D01What is the result of conductor skin effect?

AResistance increases as frequency increases because RF current flows closer to the surface

TipSkin effect: RF rides the surface, so resistance rises with frequency.

E5D02Why is it important to keep lead lengths short for components used in circuits for VHF and above?

BTo minimize inductive reactance

TipShort leads = less inductance at VHF.

E5D03What is the phase relationship between current and voltage for reactive power?

CThey are 90 degrees out of phase

TipReactive power: V and I are 90° apart.

E5D04Why are short connections used at microwave frequencies?

BTo reduce phase shift along the connection

TipMicrowaves: short connections reduce phase shift.

E5D05What parasitic characteristic causes electrolytic capacitors to be unsuitable for use at RF?

CInductance

TipElectrolytics have too much inductance for RF.

E5D06What parasitic characteristic creates an inductor’s self-resonance?

DInter-turn capacitance

TipInductor self-resonance = capacitance between turns.

E5D07What combines to create the self-resonance of a component?

BThe component’s nominal and parasitic reactance

TipSelf-resonance = the part's normal reactance + its parasitic reactance.

E5D08What is the primary cause of loss in film capacitors at RF?

DSkin effect

TipFilm capacitor RF loss = skin effect.

E5D09What happens to reactive power in ideal inductors and capacitors?

BEnergy is stored in magnetic or electric fields, but power is not dissipated

TipIdeal L and C store energy but don't burn it up.

E5D10As a conductor’s diameter increases, what is the effect on its electrical length?

DIt increases

TipFatter conductor = electrically longer.

E5D11How much real power is consumed in a circuit consisting of a 100-ohm resistor in series with a 100-ohm inductive reactance drawing 1 ampere?

B100 watts

TipOnly the resistor uses real power: I²R = 1² × 100 = 100 W.

E5D12What is reactive power?

DWattless, nonproductive power

TipReactive power = "wattless."

E6A01In what application is gallium arsenide used as a semiconductor material?

CIn microwave circuits

TipGaAs = microwaves.

E6A02Which of the following semiconductor materials contains excess free electrons?

AN-type

TipN-type = extra electrons (N = Negative).

E6A03Why does a PN-junction diode not conduct current when reverse biased?

CHoles in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region

TipReverse bias widens the depletion region, so no conduction.

E6A04What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

CAcceptor impurity

TipAcceptor = adds holes (accepts electrons). Donor adds electrons.

E6A05How does DC input impedance at the gate of a field-effect transistor (FET) compare with that of a bipolar transistor?

CAn FET has higher input impedance

TipFET input impedance is much higher than a bipolar transistor's.

E6A06What is the beta of a bipolar junction transistor?

BThe change in collector current with respect to the change in base current

TipBeta = collector current change ÷ base current change.

E6A07Which of the following indicates that a silicon NPN junction transistor is biased on?

DBase-to-emitter voltage of approximately 0.6 volts to 0.7 volts

TipSilicon NPN on = base-emitter about 0.6–0.7 V.

E6A08What is the term for the frequency at which the grounded-base current gain of a bipolar junction transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

DAlpha cutoff frequency

TipGrounded-base gain down to 0.7 = ALPHA cutoff.

E6A09What is a depletion-mode field-effect transistor (FET)?

AAn FET that exhibits a current flow between source and drain when no gate voltage is applied

TipDepletion-mode FET = conducts with zero gate voltage ("normally on").

E6A10In Figure E6-1, which is the schematic symbol for an N-channel dual-gate MOSFET?

B4

TipFigure E6-1: N-channel dual-gate MOSFET = symbol 4.

E6A11In Figure E6-1, which is the schematic symbol for a P-channel junction FET?

A1

TipFigure E6-1: P-channel JFET = symbol 1.

E6A12What is the purpose of connecting Zener diodes between a MOSFET gate and its source or drain?

DTo protect the gate from static damage

TipZeners on a MOSFET gate = static protection.

E6B01What is the most useful characteristic of a Zener diode?

BA constant voltage drop under conditions of varying current

TipZener = constant voltage.

E6B02Which characteristic of a Schottky diode makes it a better choice than a silicon junction diode for use as a power supply rectifier?

DLower forward voltage drop

TipSchottky = lower forward drop.

E6B03What property of an LED's semiconductor material determines its forward voltage drop?

BBand gap

TipLED forward voltage = the material's band gap.

E6B04What type of semiconductor device is designed for use as a voltage-controlled capacitor?

AVaractor diode

TipVoltage-controlled capacitor = VARACTOR (VARiable reACTOR).

E6B05What characteristic of a PIN diode makes it useful as an RF switch?

DLow junction capacitance

TipPIN diode RF switch = low capacitance.

E6B06Which of the following is a common use of a Schottky diode?

DAs a VHF/UHF mixer or detector

TipSchottky = VHF/UHF mixer or detector.

E6B07What causes a junction diode to fail from excessive current?

BExcessive junction temperature

TipToo much current = overheating junction.

E6B08Which of the following is a Schottky barrier diode?

AMetal-semiconductor junction

TipSchottky = metal-to-semiconductor junction.

E6B09What is a common use for point-contact diodes?

CAs an RF detector

TipPoint-contact diode = RF detector.

E6B10In Figure E6-2, which is the schematic symbol for a Schottky diode?

B6

TipFigure E6-2: Schottky diode = symbol 6.

E6B11What is used to control the attenuation of RF signals by a PIN diode?

AForward DC bias current

TipPIN diode attenuation is controlled by forward DC bias current.

E6C01What is the function of hysteresis in a comparator?

ATo prevent input noise from causing unstable output signals

TipHysteresis stops noise from making the output chatter.

E6C02What happens when the level of a comparator’s input signal crosses the threshold voltage?

BThe comparator changes its output state

TipCrosses the threshold = output flips.

E6C03What is tri-state logic?

ALogic devices with 0, 1, and high-impedance output states

TipTri-state = 0, 1, and "disconnected" (high impedance).

E6C04Which of the following is an advantage of BiCMOS logic?

CIt has the high input impedance of CMOS and the low output impedance of bipolar transistors

TipBiCMOS = CMOS high input impedance + bipolar low output impedance.

E6C05Which of the following digital logic families has the lowest power consumption?

DCMOS

TipLowest power logic = CMOS.

E6C06Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

CThe input switching threshold is about half the power supply voltage

TipCMOS switches at half the supply voltage, so it's noise-immune.

E6C07What best describes a pull-up or pull-down resistor?

BA resistor connected to the positive or negative supply used to establish a voltage when an input or output is an open circuit

TipPull-up or pull-down resistor = sets a default level when nothing's driving the line.

E6C08In Figure E6-3, which is the schematic symbol for a NAND gate?

B2

TipFigure E6-3: NAND = 2, NOR = 4, NOT = 5. So NAND = 2.

E6C09What is used to design the configuration of a field-programmable gate array (FPGA)?

BHardware description language (HDL)

TipFPGA designs are written in HDL (hardware description language).

E6C10In Figure E6-3, which is the schematic symbol for a NOR gate?

D4

TipFigure E6-3: NOR = 4. (NAND 2, NOR 4, NOT 5.)

E6C11In Figure E6-3, which is the schematic symbol for the NOT operation (inversion)?

C5

TipFigure E6-3: NOT (inverter) = 5. (NAND 2, NOR 4, NOT 5.)

E6D01What is piezoelectricity?

CA characteristic of materials that generate a voltage when stressed and that flex when a voltage is applied

TipPiezoelectric = squeeze it and get voltage; apply voltage and it flexes.

E6D02What is the equivalent circuit of a quartz crystal?

ASeries RLC in parallel with a shunt C representing electrode and stray capacitance

TipCrystal equivalent = series RLC in parallel with a shunt C.

E6D03Which of the following is an aspect of the piezoelectric effect?

AMechanical deformation of material due to the application of a voltage

TipPiezo: voltage causes deformation.

E6D04Why are cores of inductors and transformers sometimes constructed of thin layers?

BTo reduce power loss from eddy currents in the core

TipThin laminated layers reduce eddy-current losses.

E6D05How do ferrite and powdered iron compare for use in an inductor core?

CFerrite cores generally require fewer turns to produce a given inductance value

TipFerrite needs fewer turns than powdered iron for the same inductance.

E6D06What core material property determines the inductance of an inductor?

DPermeability

TipInductance depends on core PERMEABILITY.

E6D08Which of the following materials has the highest temperature stability of its magnetic characteristics?

BPowdered iron

TipMost temperature-stable core = powdered iron.

E6D09What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

CFerrite beads

TipParasitic suppressors on HF amps = ferrite beads.

E6D10What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

AToroidal cores confine most of the magnetic field within the core material

TipToroid keeps the magnetic field inside the core.

E6D11Which type of core material decreases inductance when inserted into a coil?

BBrass

TipBrass core LOWERS inductance (iron and ferrite raise it).

E6D12What causes inductor saturation?

COperation at excessive magnetic flux

TipSaturation = too much magnetic flux.

E6E01Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?

BHigher electron mobility

TipGaAs = higher electron mobility (fast at UHF).

E6E02Which of the following device packages is a through-hole type?

ADIP

TipThrough-hole = DIP.

E6E03Which of the following materials supports the highest frequency of operation when used in MMICs?

DGallium nitride

TipHighest-frequency MMIC material = gallium nitride (GaN).

E6E04Which is the most common input and output impedance of MMICs?

A50 ohms

TipMMICs are 50 Ω in and out.

E6E05Which of the following noise figure values is typical of a low-noise UHF preamplifier?

A0.5 dB

TipLow-noise UHF preamp ≈ 0.5 dB noise figure.

E6E06What characteristics of MMICs make them a popular choice for VHF through microwave circuits?

DControlled gain, low noise figure, and constant input and output impedance over the specified frequency range

TipMMICs: controlled gain, low noise, constant impedance.

E6E07What type of transmission line is often used for connections to MMICs?

DMicrostrip

TipMMIC connections = microstrip.

E6E08How is power supplied to the most common type of MMIC?

CThrough a resistor and/or RF choke connected to the amplifier output lead

TipMMIC power comes through a resistor or RF choke on the OUTPUT lead.

E6E09Which of the following component package types have the least parasitic effects at frequencies above the HF range?

DSurface mount

TipLeast parasitics = surface mount.

E6E10What advantage does surface-mount technology offer at RF compared to using through-hole components?

DAll these choices are correct

TipSurface mount advantages at RF: "All these."

E6E11What is a characteristic of DIP packaging used for integrated circuits?

DTwo rows of connecting pins on opposite sides of package (dual in-line package)

TipDIP = Dual In-line Package: two rows of pins.

E6E12Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?

CExcessive lead length

TipDIP leads are too long for UHF.

E6F01What absorbs the energy from light falling on a photovoltaic cell?

CElectrons

TipIn a solar cell, electrons absorb the light energy.

E6F02What happens to photoconductive material when light shines on it?

AResistance decreases

TipLight on photoconductive material = resistance DROPS.

E6F03What is the most common configuration of an optoisolator or optocoupler?

DAn LED and a phototransistor

TipOptoisolator = LED + phototransistor.

E6F04What is the photovoltaic effect?

BThe conversion of light to electrical energy

TipPhotovoltaic = light to electricity.

E6F05Which of the following describes an optical shaft encoder?

AA device that detects rotation by interrupting a light source with a patterned wheel

TipOptical shaft encoder = patterned wheel interrupting a light beam.

E6F06Which of these materials is most commonly used to create photoconductive devices?

CCrystalline semiconductor

TipPhotoconductors are made of crystalline semiconductor.

E6F07What is a solid-state relay?

BA device that uses semiconductors to implement the functions of an electromechanical relay

TipSolid-state relay = a relay made with semiconductors (no moving parts).

E6F08Why are optoisolators often used in conjunction with solid-state circuits that control 120 VAC circuits?

COptoisolators provide an electrical isolation between a control circuit and the circuit being switched

TipOptoisolators keep the control circuit electrically separate from 120 VAC.

E6F09What is the efficiency of a photovoltaic cell?

DThe relative fraction of light that is converted to current

TipPV efficiency = fraction of light turned into current.

E6F10What is the most common material used in power-generating photovoltaic cells?

BSilicon

TipSolar cells are usually silicon.

E6F11What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?

A0.5 volts

TipOne silicon cell ≈ 0.5 V.

E7A01Which circuit is bistable?

CA flip-flop

TipBistable = flip-flop (two stable states).

E7A02What is the function of a decade counter?

AIt produces one output pulse for every 10 input pulses

TipDecade counter = 1 output per 10 inputs.

E7A03Which of the following can divide the frequency of a pulse train by 2?

BA flip-flop

TipDivide by 2 = one flip-flop.

E7A04How many flip-flops are required to divide a signal frequency by 16?

A4

TipDivide by 16 = 2⁴, so 4 flip-flops.

E7A05Which of the following circuits continuously alternates between two states without an external clock signal?

DAstable multivibrator

TipFree-running oscillation between states = ASTABLE ("not stable").

E7A06What is a characteristic of a monostable multivibrator?

AIt switches temporarily to an alternate state for a set time

TipMonostable = flips for a set time, then returns ("one shot").

E7A07What logical operation does a NAND gate perform?

DIt produces a 0 at its output only if all inputs are 1

TipNAND = 0 only when ALL inputs are 1 (opposite of AND).

E7A08What logical operation does an OR gate perform?

AIt produces a 1 at its output if any input is 1

TipOR = 1 if ANY input is 1.

E7A09What logical operation is performed by a two-input exclusive NOR gate?

CIt produces a 0 at its output if one and only one of its inputs is 1

TipXNOR = 0 when exactly one input is 1 (1 when they match).

E7A10What is a truth table?

BA list of inputs and corresponding outputs for a digital device

TipTruth table = inputs vs outputs.

E7A11What does “positive logic” mean in reference to logic devices?

BHigh voltage represents a 1, low voltage a 0

TipPositive logic: high = 1.

E7B01For what portion of the signal cycle does each active element in a push-pull, Class AB amplifier conduct?

AMore than 180 degrees but less than 360 degrees

TipClass AB conducts more than 180° but less than 360°.

E7B02What is a Class D amplifier?

AAn amplifier that uses switching technology to achieve high efficiency

TipClass D = switching, very efficient.

E7B03What circuit is required at the output of an RF switching amplifier?

AA filter to remove harmonic content

TipSwitching amp output needs a harmonic filter.

E7B04What is the operating point of a Class A common emitter amplifier?

AApproximately halfway between saturation and cutoff

TipClass A bias = halfway between saturation and cutoff.

E7B05What can be done to prevent unwanted oscillations in an RF power amplifier?

CInstall parasitic suppressors and/or neutralize the stage

TipStop parasitic oscillation: parasitic suppressors and/or neutralization.

E7B06What is a characteristic of a grounded-grid amplifier?

BLow input impedance

TipGrounded grid = low input impedance.

E7B07Which of the following is the likely result of using a Class C amplifier to amplify a single-sideband phone signal?

DSignal distortion and excessive bandwidth

TipClass C on SSB = distortion and splatter.

E7B08Why are switching amplifiers more efficient than linear amplifiers?

BThe switching device is at saturation or cutoff most of the time

TipSwitching amps are always fully on or fully off, so little is wasted.

E7B09What is characteristic of an emitter follower (or common collector) amplifier?

DInput and output signals in-phase

TipEmitter follower: output in phase with input.

E7B10In Figure E7-1, what is the purpose of R1 and R2?

BVoltage divider bias

TipFigure E7-1: R1 and R2 = voltage divider bias.

E7B11In Figure E7-1, what is the purpose of R3?

DSelf bias

TipFigure E7-1: R3 (emitter resistor) = self bias.

E7B12What type of amplifier circuit is shown in Figure E7-1?

CCommon emitter

TipFigure E7-1 = common emitter.

E7C01How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network’s input and output?

DA capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between the input and output

TipLow-pass Pi: capacitor to ground at each end, inductor in the middle (looks like the letter π).

E7C02What is the frequency response of a T-network with series capacitors and a shunt inductor?

BHigh-pass

TipSeries capacitors + shunt inductor = high-pass (capacitors pass highs).

E7C03What is the purpose of adding an inductor to a Pi-network to create a Pi-L-network?

AGreater harmonic suppression

TipPi-L = better harmonic suppression.

E7C04How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

CIt cancels the reactive part of the impedance and changes the resistive part to the desired value

TipMatching network cancels the reactance and transforms the resistance.

E7C05Which filter type has ripple in the passband and a sharp cutoff?

DA Chebyshev filter

TipRipple in passband + sharp cutoff = Chebyshev.

E7C06What are the characteristics of an elliptical filter?

CExtremely sharp cutoff with one or more notches in the stop band

TipElliptical = super-sharp cutoff with notches.

E7C07Which describes a Pi-L network?

BA Pi-network with an additional output series inductor

TipPi-L = Pi plus a series output inductor.

E7C08Which of the following is most frequently used as a band-pass or notch filter in VHF and UHF transceivers?

BA helical filter

TipVHF/UHF band-pass or notch = helical filter.

E7C09What is a crystal lattice filter?

DA filter for low-level signals made using quartz crystals

TipCrystal lattice filter = quartz crystals, for low-level signals.

E7C10Which of the following filters is used in a 2-meter band repeater duplexer?

BA cavity filter

TipRepeater duplexer = cavity filters.

E7C11Which of the following measures a filter’s ability to reject signals in adjacent channels?

CShape factor

TipAdjacent-channel rejection = shape factor.

E7D01How does a linear electronic voltage regulator work?

DThe conduction of a control element is varied to maintain a constant output voltage

TipLinear regulator varies a control element's conduction.

E7D02How does a switchmode voltage regulator work?

BBy varying the duty cycle of pulses input to a filter

TipSwitching regulator varies pulse duty cycle into a filter.

E7D03What device is used as a stable voltage reference?

AA Zener diode

TipVoltage reference = Zener.

E7D04Which of the following describes a three-terminal voltage regulator?

BA series regulator

TipThree-terminal regulator (like a 7805) = series regulator.

E7D05Which of the following types of linear voltage regulator operates by loading the unregulated voltage source?

DA shunt regulator

TipLoads the source to regulate = shunt regulator.

E7D06What is the purpose of Q1 in the circuit shown in Figure E7-2?

CIt controls the current to keep the output voltage constant

TipFigure E7-2: Q1 = pass transistor that keeps the output constant.

E7D07What is the purpose of C2 in the circuit shown in Figure E7-2?

AIt bypasses rectifier output ripple around D1

TipFigure E7-2: C2 = bypasses ripple around D1 (the Zener).

E7D08What type of circuit is shown in Figure E7-2?

CLinear voltage regulator

TipFigure E7-2 = linear voltage regulator.

E7D09How is battery operating time calculated?

CCapacity in amp-hours divided by average current

TipBattery time = amp-hours ÷ average current.

E7D10Why is a switching type power supply less expensive and lighter than an equivalent linear power supply?

CThe high frequency inverter design uses much smaller transformers and filter components for an equivalent power output

TipSwitchers run at high frequency, so smaller transformers and filters.

E7D11What is the purpose of an inverter connected to a solar panel output?

DConvert the panel’s output from DC to AC

TipInverter = DC to AC.

E7D12What is the dropout voltage of a linear voltage regulator?

CMinimum input-to-output voltage required to maintain regulation

TipDropout = minimum input-to-output difference needed to stay regulated.

E7D13Which of the following calculates power dissipated by a series linear voltage regulator?

CVoltage difference from input to output multiplied by output current

TipSeries regulator heat = (Vin − Vout) × output current.

E7D14What is the purpose of connecting equal-value resistors across power supply filter capacitors connected in series?

DAll these choices are correct

TipEqualizing resistors balance voltages and bleed off charge: "All these."

E7D15What is the purpose of a step-start circuit in a high-voltage power supply?

DTo allow the filter capacitors to charge gradually

TipStep-start = charges the capacitors gradually.

E7E01Which of the following can be used to generate FM phone signals?

BReactance modulation of a local oscillator

TipFM phone: reactance modulation of the oscillator.

E7E02What is the function of a reactance modulator?

DProduce PM or FM signals by varying a capacitance

TipReactance modulator = varies capacitance to make FM or PM.

E7E03What is a frequency discriminator?

DA circuit for detecting FM signals

TipDiscriminator = FM detector.

E7E04What is one way to produce a single-sideband phone signal?

AUse a balanced modulator followed by a filter

TipSSB = balanced modulator + filter.

E7E05What is added to an FM speech channel to boost the higher audio frequencies?

DA pre-emphasis network

TipBoost high audio before transmitting = PRE-emphasis.

E7E06Why is de-emphasis used in FM communications receivers?

AFor compatibility with transmitters using phase modulation

TipDe-emphasis = compatibility with phase-modulation transmitters.

E7E07What is meant by the term “baseband” in radio communications?

BThe frequency range occupied by a message signal prior to modulation

TipBaseband = the original message signal before modulation.

E7E08What are the principal frequencies that appear at the output of a mixer?

CThe two input frequencies along with their sum and difference frequencies

TipMixer output: both inputs + sum + difference.

E7E09What occurs when the input signal levels to a mixer are too high?

ASpurious mixer products are generated

TipMixer overdriven = spurious products.

E7E10How does a diode envelope detector function?

ABy rectification and filtering of RF signals

TipEnvelope detector = rectify + filter.

E7E11Which type of detector is used for demodulating SSB signals?

CProduct detector

TipSSB = product detector.

E7F01What is meant by “direct sampling” in software defined radios?

CIncoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal

TipDirect sampling = digitize RF directly, no mixing.

E7F02What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

AAn adaptive filter

TipDSP noise removal = adaptive filter.

E7F03What type of digital signal processing filter is used to generate an SSB signal?

CA Hilbert-transform filter

TipDSP SSB generation = Hilbert transform.

E7F04Which method generates an SSB signal using digital signal processing?

DSignals are combined in quadrature phase relationship

TipDSP SSB = signals combined in quadrature (90°).

E7F05How frequently must an analog signal be sampled to be accurately reproduced?

BAt least twice the rate of the highest frequency component of the signal

TipNyquist: sample at least twice the highest frequency.

E7F06What is the minimum number of bits required to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

D10 bits

Tip1 V ÷ 1 mV = 1000 steps. 2¹⁰ = 1024, so 10 bits.

E7F07What function is performed by a Fast Fourier Transform?

CConverting signals from the time domain to the frequency domain

TipFFT = time domain to frequency domain.

E7F08What is the function of decimation?

BReducing the effective sample rate by removing samples

TipDecimation = lower the sample rate by dropping samples.

E7F09Why is an anti-aliasing filter required in a decimator?

AIt removes high-frequency signal components that would otherwise be reproduced as lower frequency components

TipAnti-alias filter removes highs that would fold down into fake lows.

E7F10What aspect of receiver analog-to-digital conversion determines the maximum receive bandwidth of a direct-sampling software defined radio (SDR)?

ASample rate

TipDirect-sampling SDR bandwidth = sample rate.

E7F11What sets the minimum detectable signal level for a direct-sampling software defined receiver in the absence of atmospheric or thermal noise?

BReference voltage level and sample width in bits

TipMinimum signal = ADC reference voltage + number of bits.

E7F12Which of the following is generally true of Finite Impulse Response (FIR) filters?

AFIR filters can delay all frequency components of the signal by the same amount

TipFIR filters delay all frequencies equally (linear phase).

E7F13What is the function of taps in a digital signal processing filter?

DProvide incremental signal delays for filter algorithms

TipTaps = small delays used by the filter math.

E7F14Which of the following would allow a digital signal processing filter to create a sharper filter response?

BMore taps

TipSharper DSP filter = more taps.

E7G01What is the typical output impedance of an op-amp?

AVery low

TipOp-amp output impedance = very low.

E7G02What is the frequency response of the circuit in E7-3 if a capacitor is added across the feedback resistor?

BLow-pass filter

TipCapacitor across the feedback resistor = low-pass (it shorts the highs).

E7G03What is the typical input impedance of an op-amp?

DVery high

TipOp-amp input impedance = very high.

E7G04What is meant by the term “op-amp input offset voltage”?

CThe differential input voltage needed to bring the open loop output voltage to zero

TipOffset voltage = the input difference needed to zero the output.

E7G05How can unwanted ringing and audio instability be prevented in an op-amp audio filter?

ARestrict both gain and Q

TipPrevent ringing: limit gain and Q.

E7G06What is the gain-bandwidth of an operational amplifier?

BThe frequency at which the open-loop gain of the amplifier equals one

TipGain-bandwidth = frequency where open-loop gain = 1.

E7G07What voltage gain can be expected from the circuit in Figure E7-3 when R1 is 10 ohms and RF is 470 ohms?

C47

TipInverting gain = RF ÷ R1 = 470 ÷ 10 = 47.

E7G08How does the gain of an ideal operational amplifier vary with frequency?

DIt does not vary with frequency

TipIdeal op-amp: gain doesn't change with frequency.

E7G09What will be the output voltage of the circuit shown in Figure E7-3 if R1 is 1,000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

D-2.3 volts

TipGain = −10,000 ÷ 1,000 = −10. −10 × 0.23 = −2.3 V (inverting).

E7G10What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 1,800 ohms and RF is 68 kilohms?

C38

Tip68,000 ÷ 1,800 ≈ 38.

E7G11What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 3,300 ohms and RF is 47 kilohms?

B14

Tip47,000 ÷ 3,300 ≈ 14.

E7G12What is an operational amplifier?

AA high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance

TipOp-amp = high-gain, direct-coupled differential amp: high Z in, low Z out.

E7H01What are three common oscillator circuits?

DColpitts, Hartley, and Pierce

TipOscillators: Colpitts, Hartley, Pierce.

E7H02What is a microphonic?

CChanges in oscillator frequency caused by mechanical vibration

TipMicrophonics = frequency changes from vibration.

E7H03What is a phase-locked loop?

CAn electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator

TipPLL = phase detector + low-pass filter + VCO + reference.

E7H04How is positive feedback supplied in a Colpitts oscillator?

CThrough a capacitive divider

TipColpitts = Capacitive divider ("C for Colpitts"). Hartley uses a tapped inductor.

E7H05How is positive feedback supplied in a Pierce oscillator?

DThrough a quartz crystal

TipPierce = feedback through a crystal ("Pierce the crystal").

E7H06Which of these functions can be performed by a phase-locked loop?

BFrequency synthesis and FM demodulation

TipPLL: frequency synthesis and FM demodulation.

E7H07How can an oscillator’s microphonic responses be reduced?

DMechanically isolate the oscillator circuitry from its enclosure

TipStop microphonics: mechanically isolate the oscillator.

E7H08Which of the following components can be used to reduce thermal drift in crystal oscillators?

ANP0 capacitors

TipThermal drift: NP0 capacitors (zero temperature coefficient).

E7H09What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital-to-analog converter, and a low-pass anti-alias filter?

AA direct digital synthesizer

TipPhase accumulator + lookup table + DAC = DDS.

E7H10What information is contained in the lookup table of a direct digital synthesizer (DDS)?

BAmplitude values that represent the desired waveform

TipDDS lookup table = waveform amplitude values.

E7H11What are the major spectral impurity components of direct digital synthesizers?

CSpurious signals at discrete frequencies

TipDDS impurities = spurs at discrete frequencies.

E7H12Which of the following ensures that a crystal oscillator operates on the frequency specified by the crystal manufacturer?

BProvide the crystal with a specified parallel capacitance

TipTo hit the crystal's exact frequency, give it the specified parallel capacitance.

E7H13Which of the following is a technique for providing highly accurate and stable oscillators needed for microwave transmission and reception?

DAll these choices are correct

TipStable microwave oscillators: several techniques. "All these."

E8A01What technique shows that a square wave is made up of a sine wave and its odd harmonics?

AFourier analysis

TipSquare wave = sine + odd harmonics, shown by Fourier analysis.

E8A02Which of the following is a type of analog-to-digital conversion?

ASuccessive approximation

TipADC type = successive approximation.

E8A03Which of the following describes a signal in the time domain?

BAmplitude at different times

TipTime domain = amplitude over time.

E8A04What is “dither” with respect to analog-to-digital converters?

BA small amount of noise added to the input signal to reduce quantization noise

TipDither = tiny noise added to reduce quantization noise.

E8A05What is the benefit of making voltage measurements with a true-RMS calculating meter?

DRMS is measured for both sinusoidal and non-sinusoidal signals

TipTrue-RMS works on any waveform, not just sine waves.

E8A06What is the approximate ratio of PEP-to-average power in an unprocessed single-sideband phone signal?

A2.5 to 1

TipSSB PEP-to-average ≈ 2.5:1.

E8A07What determines the PEP-to-average power ratio of an unprocessed single-sideband phone signal?

BSpeech characteristics

TipThat ratio depends on speech characteristics.

E8A08Why are direct or flash conversion analog-to-digital converters used for a software defined radio?

CVery high speed allows digitizing high frequencies

TipFlash ADCs are very fast, so they can digitize high frequencies.

E8A09How many different input levels can be encoded by an analog-to-digital converter with 8-bit resolution?

D256

Tip8 bits = 2⁸ = 256 levels.

E8A10What is the purpose of a low-pass filter used at the output of a digital-to-analog converter?

CRemove spurious sampling artifacts from the output signal

TipDAC output low-pass removes sampling artifacts.

E8A11Which of the following is a measure of the quality of an analog-to-digital converter?

ATotal harmonic distortion

TipADC quality = total harmonic distortion.

E8B01What is the modulation index of an FM signal?

AThe ratio of frequency deviation to modulating signal frequency

TipModulation index = deviation ÷ modulating frequency.

E8B02How does the modulation index of a phase-modulated emission vary with RF carrier frequency?

DIt does not depend on the RF carrier frequency

TipPM modulation index doesn't depend on the carrier frequency.

E8B03What is the modulation index of an FM phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency if the highest modulating frequency is 1000 Hz?

A3

Tip3000 ÷ 1000 = 3.

E8B04What is the modulation index of an FM phone signal having a maximum carrier deviation of plus or minus 6 kHz if the highest modulating frequency is 2 kHz?

B3

Tip6 kHz ÷ 2 kHz = 3.

E8B05What is the deviation ratio of an FM phone signal having a maximum frequency swing of plus or minus 5 kHz if the highest modulation frequency is 3 kHz?

D1.67

TipDeviation ratio = max deviation ÷ max audio: 5 ÷ 3 = 1.67.

E8B06What is the deviation ratio of an FM phone signal having a maximum frequency swing of plus or minus 7.5 kHz if the highest modulation frequency is 3.5 kHz?

A2.14

Tip7.5 ÷ 3.5 = 2.14.

E8B07Orthogonal frequency-division multiplexing (OFDM) is a technique used for which types of amateur communication?

ADigital modes

TipOFDM = digital modes.

E8B08What describes orthogonal frequency-division multiplexing (OFDM)?

DA digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference

TipOFDM = subcarriers spaced to avoid intersymbol interference.

E8B09What is deviation ratio?

BThe ratio of the maximum carrier frequency deviation to the highest audio modulating frequency

TipDeviation ratio = max deviation ÷ highest audio frequency.

E8B10What is frequency division multiplexing (FDM)?

BDividing the transmitted signal into separate frequency bands that each carry a different data stream

TipFDM = divide by frequency.

E8B11What is digital time division multiplexing?

BTwo or more signals are arranged to share discrete time slots of a data transmission

TipTDM = share time slots.

E8C01What is Quadrature Amplitude Modulation or QAM?

BTransmission of data by modulating the amplitude of two carriers of the same frequency but 90 degrees out of phase

TipQAM = two carriers, same frequency, 90° apart, amplitude modulated.

E8C02What is the definition of symbol rate in a digital transmission?

CThe rate at which the waveform changes to convey information

TipSymbol rate = how fast the waveform changes.

E8C03Why should the phase of a PSK signal be changed at the zero crossing of the RF signal?

ATo minimize bandwidth

TipChange PSK phase at the zero crossing to minimize bandwidth.

E8C04What technique minimizes the bandwidth of a PSK31 signal?

CUse of sinusoidal data pulses

TipPSK31 stays narrow with sinusoidal (smooth) pulses.

E8C05What is the approximate bandwidth of a 13-WPM International Morse Code transmission?

C52 Hz

TipCW bandwidth ≈ 4 × WPM = 4 × 13 = 52 Hz.

E8C06What is the bandwidth of an FT8 signal?

B50 Hz

TipFT8 ≈ 50 Hz.

E8C07What is the bandwidth of a 4,800-Hz frequency shift, 9,600-baud ASCII FM transmission?

A15.36 kHz

TipBW = baud + 1.2 × shift = 9600 + 1.2 × 4800 = 15,360 Hz = 15.36 kHz.

E8C08How does ARQ accomplish error correction?

DIf errors are detected, a retransmission is requested

TipARQ = ask for a resend.

E8C09Which digital code allows only one bit to change between sequential code values?

DGray code

TipOne bit changes at a time = Gray code.

E8C10How can data rate be increased without increasing bandwidth?

CUsing a more efficient digital code

TipMore data, same bandwidth = more efficient code.

E8C11What is the relationship between symbol rate and baud?

AThey are the same

TipSymbol rate = baud.

E8C12What factors affect the bandwidth of a transmitted CW signal?

CKeying speed and shape factor (rise and fall time)

TipCW bandwidth depends on speed and rise/fall time.

E8C13What is described by the constellation diagram of a QAM or QPSK signal?

BThe possible phase and amplitude states for each symbol

TipConstellation = the possible phase and amplitude states.

E8C14What type of addresses do nodes have in a mesh network?

CInternet Protocol (IP)

TipMesh nodes use IP addresses.

E8C15What technique do individual nodes use to form a mesh network?

CDiscovery and link establishment protocols

TipMesh forms by discovery and link protocols.

E8D01Why are received spread spectrum signals resistant to interference?

ASignals not using the spread spectrum algorithm are suppressed in the receiver

TipSpread spectrum rejects signals that don't match its code.

E8D02What spread spectrum communications technique uses a high-speed binary bit stream to shift the phase of an RF carrier?

BDirect sequence

TipBit stream shifting phase = direct sequence.

E8D03Which describes spread spectrum frequency hopping?

DRapidly varying the frequency of a transmitted signal according to a pseudorandom sequence

TipFrequency hopping = pseudorandom frequency changes.

E8D04What is the primary effect of extremely short rise or fall time on a CW signal?

CThe generation of key clicks

TipToo-fast rise or fall = key clicks.

E8D05What is the most common method of reducing key clicks?

AIncrease keying waveform rise and fall times

TipFix key clicks: slow the rise and fall times.

E8D06What is the advantage of including parity bits in ASCII characters?

DSome types of errors can be detected

TipParity = detects some errors.

E8D07What is a common cause of overmodulation of AFSK signals?

DExcessive transmit audio levels

TipAFSK overmodulation = too much audio.

E8D08What parameter evaluates distortion of an AFSK signal caused by excessive input audio levels?

DIntermodulation Distortion (IMD)

TipAFSK distortion = IMD.

E8D09What is considered an acceptable maximum IMD level for an idling PSK signal?

D-30 dB

TipAcceptable PSK IMD = −30 dB.

E8D10What are some of the differences between the Baudot digital code and ASCII?

BBaudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code

TipBaudot = 5 bits with letters/figures shift codes. ASCII = 7 or 8 bits, no shift codes.

E8D11What is one advantage of using ASCII code for data communications?

CIt is possible to transmit both uppercase and lowercase text

TipASCII has upper AND lower case.

E9A01What is an isotropic radiator?

CA hypothetical, lossless antenna having equal radiation intensity in all directions used as a reference for antenna gain

TipIsotropic = imaginary antenna radiating equally in all directions (the reference).

E9A02What is the effective radiated power (ERP) of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

D286 watts

Tip7 − 2 − 2.2 = +2.8 dB ≈ 1.9×. 150 × 1.9 ≈ 286 W.

E9A03What term describing total radiated power takes into account all gains and losses?

CEffective radiated power

TipAll gains and losses = ERP.

E9A04Which of the following factors affect the feed point impedance of an antenna?

BAntenna height

TipHeight affects feed point impedance.

E9A05What does the term “ground gain” mean?

DAn increase in signal strength from ground reflections in the environment of the antenna

TipGround gain = boost from ground reflections.

E9A06What is the effective radiated power (ERP) of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

A317 watts

Tip10 − 4 − 3.2 − 0.8 = +2 dB ≈ 1.58×. 200 × 1.58 ≈ 317 W.

E9A07What is the effective isotropic radiated power (EIRP) of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

B252 watts

Tip7 − 2 − 2.8 − 1.2 = +1 dB ≈ 1.26×. 200 × 1.26 ≈ 252 W EIRP.

E9A08Which frequency band has the smallest first Fresnel zone?

A5.8 GHz

TipSmallest Fresnel zone = highest frequency: 5.8 GHz.

E9A09What is antenna efficiency?

BRadiation resistance divided by total resistance

TipEfficiency = radiation resistance ÷ total resistance.

E9A10Which of the following improves the efficiency of a ground-mounted quarter-wave vertical antenna?

AInstalling a ground radial system

TipGround-mounted vertical: add radials.

E9A11Which of the following determines ground losses for a ground-mounted vertical antenna operating on HF?

CSoil conductivity

TipGround loss = soil conductivity.

E9A12How much gain does an antenna have compared to a half-wavelength dipole if it has 6 dB gain over an isotropic radiator?

A3.85 dB

TipdBd = dBi − 2.15: 6 − 2.15 = 3.85 dB.

E9B01What is the 3 dB beamwidth of the antenna radiation pattern shown in Figure E9-1?

B50 degrees

TipFigure E9-1: 3 dB beamwidth = 50°.

E9B02What is the front-to-back ratio of the antenna radiation pattern shown in Figure E9-1?

D18 dB

TipFigure E9-1: front-to-back = 18 dB.

E9B03What is the front-to-side ratio of the antenna radiation pattern shown in Figure E9-1?

D14 dB

TipFigure E9-1: front-to-side = 14 dB. (E9-1 numbers: 50°, 18 dB, 14 dB.)

E9B04What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

B28 dB

TipFigure E9-2: front-to-back = 28 dB.

E9B05What type of antenna pattern is shown in Figure E9-2?

AElevation

TipFigure E9-2 is an ELEVATION pattern (side view).

E9B06What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

C7.5 degrees

TipFigure E9-2: peak at 7.5°. (E9-2 numbers: 28 dB, elevation, 7.5°.)

E9B07What is the difference in radiated power between a lossless antenna with gain and an isotropic radiator driven by the same power?

CThey are the same

TipGain just redirects power. Total radiated power is the same.

E9B08What is the far field of an antenna?

DThe region where the shape of the radiation pattern no longer varies with distance

TipFar field = the pattern's shape stops changing with distance.

E9B09What type of analysis is commonly used for modeling antennas?

BMethod of Moments

TipAntenna modeling = Method of Moments (NEC).

E9B10What is the principle of a Method of Moments analysis?

AA wire is modeled as a series of segments, each having a uniform value of current

TipMoM = wire chopped into segments, each with uniform current.

E9B11What is a disadvantage of decreasing the number of wire segments in an antenna model below 10 segments per half-wavelength?

CThe computed feed point impedance may be incorrect

TipToo few segments = wrong feed impedance.

E9C01What type of radiation pattern is created by two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

DA figure-eight oriented along the axis of the array

Tip½ λ apart, 180° out of phase = figure-8 ALONG the array axis (end-fire).

E9C02What type of radiation pattern is created by two 1/4-wavelength vertical antennas spaced 1/4-wavelength apart and fed 90 degrees out of phase?

ACardioid

Tip¼ λ apart, 90° out of phase = cardioid.

E9C03What type of radiation pattern is created by two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed in phase?

CA figure-eight broadside to the axis of the array

Tip½ λ apart, in phase = figure-8 BROADSIDE to the array.

E9C04What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

BAdditional lobes form with major lobes increasingly aligned with the axis of the antenna

TipLonger long-wire = more lobes, swinging toward the wire's axis.

E9C05What is the purpose of feeding an off-center-fed dipole (OCFD) between the center and one end instead of at the midpoint?

ATo create a similar feed point impedance on multiple bands

TipOff-center feed = similar impedance on multiple bands.

E9C06What is the effect of adding a terminating resistor to a rhombic or long-wire antenna?

BIt changes the radiation pattern from bidirectional to unidirectional

TipTerminating resistor = bidirectional becomes unidirectional.

E9C07What is the approximate feed point impedance at the center of a two-wire half-wave folded dipole antenna?

A300 ohms

TipFolded dipole ≈ 300 Ω (4 × 75).

E9C08What is a folded dipole antenna?

CA half-wave dipole with an additional parallel wire connecting its two ends

TipFolded dipole = dipole + a parallel wire joining its ends.

E9C09Which of the following describes a G5RV antenna?

AA wire antenna center-fed through a specific length of open-wire line connected to a balun and coaxial feed line

TipG5RV = center-fed through a specific length of ladder line, then a balun and coax.

E9C10Which of the following describes a Zepp antenna?

BAn end-fed half-wavelength dipole

TipZepp = end-fed half-wave.

E9C11How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus soil?

DRadiation at low angles increases

TipVertical over seawater = more low-angle radiation.

E9C12Which of the following describes an extended double Zepp antenna?

CA center-fed 1.25-wavelength dipole antenna

TipExtended double Zepp = center-fed 1.25 λ.

E9C13How does the radiation pattern of a horizontally polarized antenna vary with increasing height above ground?

BThe takeoff angle of the lowest elevation lobe decreases

TipHigher horizontal antenna = lower takeoff angle.

E9C14How does the radiation pattern of a horizontally-polarized antenna mounted above a long slope compare with the same antenna mounted above flat ground?

BThe main lobe takeoff angle decreases in the downhill direction

TipOver a downhill slope = lower takeoff angle in that direction.

E9D01How much does the gain of an ideal parabolic reflector antenna increase when the operating frequency is doubled?

D6 dB

TipDish gain grows with frequency²: double the frequency = +6 dB.

E9D02How can two linearly polarized Yagi antennas be used to produce circular polarization?

CArrange two Yagis on the same axis and perpendicular to each other with the driven elements at the same point on the boom and fed 90 degrees out of phase

TipCircular polarization: two Yagis at right angles, fed 90° apart.

E9D03What is the most efficient location for a loading coil on an electrically short whip?

ANear the center of the vertical radiator

TipBest loading coil spot = near the center of the whip.

E9D04Why should antenna loading coils have a high ratio of reactance to resistance?

CTo maximize efficiency

TipLoading coil: high X/R (high Q) = efficient.

E9D05Approximately how long is a Yagi’s driven element?

D1/2 wavelength

TipYagi driven element = ½ λ.

E9D06What happens to SWR bandwidth when one or more loading coils are used to resonate an electrically short antenna?

BIt is decreased

TipLoading coils = narrower SWR bandwidth.

E9D07What is an advantage of top loading an electrically short HF vertical antenna?

DImproved radiation efficiency

TipTop loading = better efficiency.

E9D08What happens as the Q of an antenna increases?

BSWR bandwidth decreases

TipHigher Q = narrower bandwidth.

E9D09What is the function of a loading coil in an electrically short antenna?

DTo resonate the antenna by cancelling the capacitive reactance

TipLoading coil cancels the short antenna's capacitive reactance.

E9D10How does radiation resistance of a base-fed whip antenna change below its resonant frequency?

BRadiation resistance decreases

TipBelow resonance, radiation resistance DROPS.

E9D11Why do most two-element Yagis with normal spacing have a reflector instead of a director?

DHigher gain

Tip2-element Yagi: a reflector gives more gain than a director.

E9D12What is the purpose of making a Yagi’s parasitic elements either longer or shorter than resonance?

CControl of phase shift

TipParasitic element length controls phase shift.

E9E01Which matching system for Yagi antennas requires the driven element to be insulated from the boom?

BBeta or hairpin

TipBeta/hairpin needs the driven element insulated from the boom (gamma doesn't).

E9E02What antenna matching system matches coaxial cable to an antenna by connecting the shield to the center of the antenna and the conductor a fraction of a wavelength to one side?

AGamma match

TipShield at center, conductor tapped off to one side = gamma match.

E9E03What matching system uses a short length of transmission line connected in parallel with the feed line at or near the feed point?

DStub match

TipShort line in parallel at the feed point = stub match.

E9E04What is the purpose of the series capacitor in a gamma match?

BTo cancel unwanted inductive reactance

TipGamma series capacitor cancels inductive reactance.

E9E05What Yagi driven element feed point impedance is required to use a beta or hairpin matching system?

ACapacitive (driven element electrically shorter than 1/2 wavelength)

TipHairpin needs a capacitive driven element (slightly short).

E9E06Which of these transmission line impedances would be suitable for constructing a quarter-wave Q-section for matching a 100-ohm feed point impedance to a 50-ohm transmission line?

C75 ohms

TipQ-section: Z = √(100 × 50) ≈ 71, so 75 Ω coax.

E9E07What parameter describes the interaction of a load and transmission line?

BReflection coefficient

TipLoad-line interaction = reflection coefficient.

E9E08What is a use for a Wilkinson divider?

CTo divide power equally between two 50-ohm loads while maintaining 50-ohm input impedance

TipWilkinson = splits power equally while keeping 50 Ω.

E9E09Which of the following is used to shunt feed a grounded tower at its base?

CGamma match

TipShunt-feeding a grounded tower = gamma match.

E9E11What is the purpose of using multiple driven elements connected through phasing lines?

ATo control the antenna’s radiation pattern

TipPhased driven elements = control the pattern.

E9F01What is the velocity factor of a transmission line?

DThe velocity of a wave in the transmission line divided by the velocity of light in a vacuum

TipVelocity factor = speed in line ÷ speed of light.

E9F02Which of the following has the biggest effect on the velocity factor of a transmission line?

CThe insulating dielectric material

TipVelocity factor depends on the dielectric.

E9F03Why is the electrical length of a coaxial cable longer than its physical length?

DElectromagnetic waves move more slowly in a coaxial cable than in air

TipWaves are slower in coax, so it's electrically longer.

E9F04What impedance does a 1/2-wavelength transmission line present to an RF generator when the line is shorted at the far end?

BVery low impedance

Tip½ λ line repeats the load: shorted = very low.

E9F05What is microstrip?

DPrecision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies

TipMicrostrip = PCB traces over a ground plane.

E9F06What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically 1/2 wavelength long at 14.10 MHz?

C10.6 meters

Tipλ = 300 ÷ 14.1 = 21.3 m. Half = 10.6 m (air line, VF ≈ 1).

E9F07How does parallel conductor transmission line compare to coaxial cable with a plastic dielectric?

ALower loss

TipLadder line = lower loss than coax.

E9F08Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric coaxial cable, assuming all other parameters are the same?

DAll these choices are correct

TipFoam vs solid: different velocity factor, loss, power handling... "All these."

E9F09What impedance does a 1/4-wavelength transmission line present to an RF generator when the line is shorted at the far end?

AVery high impedance

Tip¼ λ INVERTS: shorted = very HIGH.

E9F10What impedance does a 1/8-wavelength transmission line present to an RF generator when the line is shorted at the far end?

CAn inductive reactance

Tip⅛ λ shorted = inductive.

E9F11What impedance does a 1/8-wavelength transmission line present to an RF generator when the line is open at the far end?

CA capacitive reactance

Tip⅛ λ open = capacitive.

E9F12What impedance does a 1/4-wavelength transmission line present to an RF generator when the line is open at the far end?

DVery low impedance

Tip¼ λ inverts: open = very LOW. (Quarter flips, half repeats.)

E9G01Which of the following can be calculated using a Smith chart?

AImpedance along transmission lines

TipSmith chart = impedance along a line.

E9G02What type of coordinate system is used in a Smith chart?

BResistance circles and reactance arcs

TipSmith chart = resistance circles + reactance arcs.

E9G03Which of the following is often determined using a Smith chart?

CImpedance and SWR values in transmission lines

TipSmith chart = impedance and SWR.

E9G04What are the two families of circles and arcs that make up a Smith chart?

CResistance and reactance

TipSmith chart families: resistance and reactance.

E9G05Which of the following is a common use for a Smith chart?

ADetermine the length and position of an impedance matching stub

TipSmith chart: find matching stub length and position.

E9G06On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

BReactance axis

TipFigure E9-3: outer circle = reactance axis.

E9G07On the Smith chart shown in Figure E9-3, what is the only straight line shown?

DThe resistance axis

TipFigure E9-3: the only straight line = resistance axis.

E9G08How is a Smith chart normalized?

CReassign the prime center’s impedance value

TipNormalize = reassign the center's impedance value.

E9G09What third family of circles is often added to a Smith chart during the process of designing impedance matching networks?

AConstant-SWR circles

TipThird family = constant-SWR circles.

E9G10What do the arcs on a Smith chart represent?

DPoints with constant reactance

TipArcs = constant reactance.

E9G11In what units are the wavelength scales on a Smith chart calibrated?

BIn fractions of transmission line electrical wavelength

TipWavelength scales are in fractions of a wavelength.

E9H01When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

DIt should be at least one wavelength long

TipBeverage: at least 1 wavelength long.

E9H02Which is generally true for 160- and 80-meter receiving antennas?

AAtmospheric noise is so high that directivity is much more important than losses

TipLow-band receiving: noise is so high that directivity matters more than loss.

E9H03What is receiving directivity factor (RDF)?

DPeak antenna gain compared to average gain over the hemisphere around and above the antenna

TipRDF = peak gain vs average over the hemisphere.

E9H04What is the purpose of placing an electrostatic shield around a small-loop direction-finding antenna?

BIt eliminates unbalanced capacitive coupling to the antenna’s surroundings, improving the depth of its nulls

TipElectrostatic shield = deeper nulls.

E9H05What challenge is presented by a small wire-loop antenna for direction finding?

AIt has a bidirectional null pattern

TipSmall loop = TWO nulls (bidirectional), so it's ambiguous.

E9H06What indicates the correct value of terminating resistance for a Beverage antenna?

DMinimum variation in SWR over the desired frequency range

TipRight Beverage termination = flattest SWR across frequency.

E9H07What is the function of a Beverage antenna’s termination resistor?

BAbsorb signals from the reverse direction

TipTermination absorbs signals from the back.

E9H08What is the function of a sense antenna?

AIt modifies the pattern of a DF antenna to provide a null in only one direction

TipSense antenna = one null instead of two.

E9H09What type of radiation pattern is created by a single-turn, terminated loop such as a pennant antenna?

ACardioid

TipPennant (terminated loop) = cardioid.

E9H10How can the output voltage of a multiple-turn receiving loop antenna be increased?

CBy increasing the number of turns and/or the area enclosed by the loop

TipMore turns or more area = more voltage.

E9H11What feature of a cardioid pattern antenna makes it useful for direction-finding antennas?

BA single null

TipCardioid = single null, so it's good for direction finding.

E0A01What is the primary function of an external earth connection or ground rod?

BLightning charge dissipation

TipGround rod = dissipates lightning.

E0A02When evaluating RF exposure levels from your station at a neighbor’s home, what must you do?

BEnsure signals from your station are less than the uncontrolled maximum permissible exposure (MPE) limits

TipNeighbors: stay under the UNCONTROLLED MPE limits.

E0A03Over what range of frequencies are the FCC human body RF exposure limits most restrictive?

C30 - 300 MHz

TipMost restrictive: 30–300 MHz (the body absorbs most there).

E0A04When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

CEach transmitter that produces 5 percent or more of its MPE limit in areas where the total MPE limit is exceeded

TipMultiple transmitters: everyone contributing 5% or more shares responsibility.

E0A05What hazard is created by operating at microwave frequencies?

BThe high gain antennas commonly used can result in high exposure levels

TipMicrowave hazard = high-gain antennas concentrate exposure.

E0A06Why are there separate electric (E) and magnetic (H) MPE limits at frequencies below 300 MHz?

DAll these choices are correct

TipSeparate E and H limits: "All these."

E0A07What is meant by “100% tie-off” regarding tower safety?

BAt least one lanyard attached to the tower at all times

Tip100% tie-off = always at least one lanyard attached.

E0A08What does SAR measure?

CThe rate at which RF energy is absorbed by the body

TipSAR = the rate the body absorbs RF.

E0A09Which of the following types of equipment are exempt from RF exposure evaluations?

CHand-held transceivers sold before May 3, 2021

TipExempt: handhelds sold before May 3, 2021.

E0A10When must an RF exposure evaluation be performed on an amateur station operating on 80 meters?

AAn evaluation must always be performed

Tip80 m: an evaluation is ALWAYS required.

E0A11To what should lanyards be attached while climbing?

DTower legs

TipLanyards attach to the tower LEGS.

E0A12Where should a shock-absorbing lanyard be attached to a tower when working above ground?

AAbove the climber’s head level

TipShock-absorbing lanyard attaches above your head.