1. What is meant by receiver overload?
    A. Interference caused by turning the volume up too high.
    B. Too much current from the power supply.
    C. Interference caused by strong signals from a nearby transmitter.
    D. Too much voltage from the power supply.

  2. What is one way to tell if radio frequency interference to a receiver is caused by front-end overload?
    A. If grounding the receiver makes the problem worse.
    B. If connecting a low pass filter to the receiver greatly cuts down the interference.
    C. If the interference is about the same no matter what frequency is used for the transmitter.
    D. If connecting a low pass filter to the transmitter greatly cuts down the interference.

  3. If a neighbour reports television interference whenever you transmit, no matter what band you use, what is probably the cause of the interference?
    A. Incorrect antenna length.
    B. Receiver VR tube discharge.
    C. Receiver overload.
    D. Too little transmitter harmonic suppression.

  4. What type of a filter should be connected to a TV receiver as a first step in trying to prevent RF overload from an amateur HF station transmission?
    A. High-pass.
    B. Low-pass.
    C. Band-pass.
    D. No filter.

  5. When the signal from a transmitter overloads the audio stages of a broadcast receiver, the transmitted signal:
    A. is distorted on voice peaks
    B. can appear wherever the receiver is tuned
    C. appears only on one frequency
    D. appears only when a station is tuned

  6. Cross-modulation of a broadcast receiver by a nearby transmitter would be noticed in the receiver as:
    A. interference only when a broadcast signal is tuned
    B. the undesired signal in the background of the desired signal
    C. distortion on transmitted voice peaks
    D. interference continuously across the dial

  7. What is cross-modulation interference?
    A. Interference between two transmitters of different modulation type.
    B. Interference caused by audio rectification in the receiver preamplifier.
    C. Harmonic distortion of the transmitted signal.
    D. Modulation from an unwanted signal is heard in addition to the desired signal.

  8. What is the term used to refer to the condition where the signals from a very strong station is superimposed on other signals being received?
    A. Receiver quieting.
    B. Cross-modulation interference.
    C. Capture effect.
    D. Intermodulation distortion.

  9. What is the result of cross-modulation?
    A. Receiver quieting.
    B. A decrease in modulation level of transmitted signals.
    C. Inverted sidebands in the final stage of the amplifier.
    D. The modulation of an unwanted signal is heard on the desired signal.

  10. If a television receiver suffers from cross-modulation when a nearby amateur transmitter is operating at 14 MHz, which of the following cures may be effective?
    A. A low pass filter attached to the antenna output of the transmitter.
    B. A high pass filter attached to the antenna output of the transmitter.
    C. A high pass filter attached to the antenna input of the television.
    D. A low pass filter attached to the antenna input of the television.

  11. How can cross-modulation be reduced?
    A. By installing a suitable filter at the receiver.
    B. By using a better antenna.
    C. By increasing the receiver RF gain while decreasing the AF gain.
    D. By adjusting the passband tuning.

  12. What device would you install to reduce or eliminate audio-frequency interference to home entertainment systems?
    A. Bypass resistors.
    B. Metal-oxide varistors.
    C. Bypass capacitors.
    D. Bypass inductors.

  13. What should be done if a properly operating amateur station is the cause of interference to a nearby telephone?
    A. Ground and shield the local telephone distribution amplifier.
    B. Stop transmitting whenever the telephone is in use.
    C. Ask the telephone company to install RFI filters.
    D. Make internal adjustments to the telephone equipment.

  14. What sound is heard from a public address system if audio rectification of a nearby single-sideband phone transmission occurs?
    A. Clearly audible speech from the transmitter’s signals.
    B. On-and-off humming or clicking.
    C. Distorted speech from the transmitter’s signals.
    D. A steady hum whenever the transmitter’s carrier is on the air.

  15. What sound is heard from a public address system if audio rectification of a nearby CW transmission occurs?
    A. Audible, possibly distorted speech.
    B. Muffled, severely distorted speech.
    C. A steady whistling.
    D. On-and-off humming or clicking.

  16. How can you minimize the possibility of audio rectification of your transmitter’s signals?
    A. By installing bypass capacitors on all power supply rectifiers.
    B. By using CW emissions only.
    C. By ensuring all station equipment is properly grounded.
    D. By using a solid-state transmitter.

  17. An amateur transmitter is being heard across the entire dial of a broadcast receiver. The receiver is most possibly suffering from:
    A. harmonic interference from the transmitter
    B. cross-modulation or audio rectification in the receiver
    C. poor image rejection
    D. splatter from the transmitter

  18. Cross-modulation is usually caused by:
    A. rectification of strong signals
    B. harmonics generated at the transmitter
    C. improper filtering in the transmitter
    D. lack of receiver sensitivity and selectivity

  19. What device can be used to minimize the effect of RF pickup by audio wires connected to stereo speakers, intercom amplifiers, telephones, etc.?
    A. Magnet.
    B. Attenuator.
    C. Diode.
    D. Ferrite core.

  20. Stereo speaker leads often act as antennas to pick up RF signals. What is one method you can use to minimize this effect?
    A. Shorten the leads.
    B. Lengthen the leads.
    C. Connect the speaker through an audio attenuator.
    D. Connect a diode across the speaker.

  21. One method of preventing RF from entering a stereo set through the speaker leads is to wrap each of the speaker leads around a:
    A. copper bar
    B. iron bar
    C. ferrite core
    D. wooden dowel

  22. Stereo amplifiers often have long leads which pick up transmitted signals because they act as:
    A. transmitting antennas
    B. RF attenuators
    C. frequency discriminators
    D. receiving antennas

  23. How can you prevent key-clicks?
    A. By increasing power.
    B. By using a key-click filter.
    C. By using a better power supply.
    D. By sending CW more slowly.

  24. If someone tells you that signals from your hand-held transceiver are interfering with other signals on a frequency near yours, what may be the cause?
    A. Your hand-held may be transmitting spurious emissions.
    B. You may need a power amplifier for you hand-held.
    C. Your hand-held may have chirp from weak batteries.
    D. You may need to turn the volume up on your hand-held.

  25. If your transmitter sends signals outside the band where it is transmitting, what is this called?
    A. Side tones.
    B. Transmitter chirping.
    C. Spurious emissions.
    D. Off-frequency emissions.

  26. What problem may occur if your transmitter is operated without the cover and other shielding in place?
    A. It may transmit a weak signal.
    B. It may transmit spurious emissions.
    C. It may interfere with other stations operating nears its frequency.
    D. It may transmit a chirpy signal.

  27. In Morse code transmission, local RF interference (key-clicks) is produced by:
    A. the making and breaking of the circuit at the Morse key
    B. frequency shifting by poor voltage regulation
    C. the power amplifier, and is caused by high frequency parasitics
    D. poor waveshaping cause by a poor voltage regulator

  28. Key-clicks, heard from a Morse code transmitter at a distant receiver, are the result of:
    A. power supply hum modulating the carrier
    B. too sharp rise and decay time of the carrier
    C. sparks emitting RF from the key contacts
    D. changes in oscillator frequency on keying

  29. In a Morse code transmission, local RF interference (key-clicks) is produced by:
    A. shift in frequency when keying the transmitter
    B. sparking at the key contacts
    C. sudden movement in the receiver loudspeaker
    D. poor shaping of the waveform

  30. Key-clicks can be suppressed by:
    A. inserting a choke and capacitors at the key
    B. turning the receiver down
    C. regulating the oscillator supply voltage
    D. using a choke in the RF power output

  31. A parasitic oscillation:
    A. is generated by parasitic elements of a Yagi beam
    B. does not cause any radio interference
    C. is produced in a transmitter oscillator stage
    D. is an unwanted signal developed in a transmitter

  32. Parasitic oscillations in the RF power amplifier stage of a transmitter may be found:
    A. at high or low frequencies
    B. on harmonic frequencies
    C. at high frequencies only
    D. on harmonics of the transmitter frequency

  33. Transmitter RF amplifiers can generate parasitic oscillations:
    A. on VHF frequencies only
    B. on the transmitter fundamental frequency
    C. on either side of the transmitter frequency
    D. on harmonics of the transmitter frequency

  34. If a neighbour reports television interference on one or two channels only when you transmit on 15 meters, what is probably the cause of the interference?
    A. De-ionization of the ionosphere near your neighbour’s TV antenna.
    B. Harmonic radiation from your transmitter.
    C. TV receiver front-end overload.
    D. Too much low pass filtering on the transmitter.

  35. What is meant by harmonic radiation?
    A. Unwanted signals on frequencies that are multiples of the fundamental (chosen) frequency.
    B. Unwanted signals that are combined with a 60 Hz hum.
    C. Unwanted signals caused by sympathetic vibrations from a nearby
    transmitter.
    D. Signals that cause skip propagation to occur.

  36. Why is harmonic radiation from an amateur station not wanted?
    A. It uses large amounts of electrical power.
    B. It may cause sympathetic vibrations in nearby transmitters.
    C. It may cause auroras in the air.
    D. It may cause interference to other stations and may result in out-of-band signals.

  37. What type of interference may come from a multi-band antenna connected to a poorly tuned transmitter?
    A. Parasitic excitation.
    B. Harmonic radiation.
    C. Intermodulation.
    D. Auroral distortion.

  38. If you are told your station was heard on 21375 kHz, but at the time you were operating on 7125 kHz, what is one reason this could happen?
    A. Your transmitter’s power supply filter choke was bad.
    B. You were sending CW too fast.
    C. Your transmitter was radiating harmonic signals.
    D. Your transmitter’s power supply filter capacitor was bad.

  39. What causes splatter interference?
    A. Keying a transmitter too fast.
    B. Signals from a transmitter’s output circuit are being sent back to its input circuit.
    C. The transmitting antenna is the wrong length.
    D. Overmodulation of a transmitter.

  40. Your amateur radio transmitter appears to be causing interference to the television on channel 3 (60-66 MHz) when you are transmitting on the 15 meter band. Other channels are not affected. The most likely cause is:
    A. no high-pass filter on the TV
    B. a bad ground on the transmitter
    C. harmonic radiation from the transmitter
    D. front-end overload of the TV

  41. One possible cause of TV interference by harmonics from a SSB transmitter is from “flat topping” – driving the final amplifier into non-linear operation. The most appropriate remedy for this is:
    A. retune transmitter output
    B. use another antenna
    C. reduce microphone gain
    D. reduce oscillator output

  42. In a transmitter, excessive harmonics are produced by:
    A. low SWR
    B. resonate circuits
    C. a linear amplifier
    D. overdriven stages

  43. An interfering signal from a transmitter is found to have a frequency of 57 MHz (TV channel 2 is 54-60 MHz). This signal could be the:
    A. crystal oscillator operating on its fundamental frequency
    B. seventh harmonic of an 80 meter transmission
    C. second harmonic of a 10 meter transmission
    D. third harmonic of a 15 meter transmission

  44. Harmonics may be produced in the RF power amplifier of a transmitter if:
    A. excessive drive signal is applied to it
    B. the output drive circuit is not correctly tuned
    C. the oscillator frequency is unstable
    D. modulation is applied to more than one stage

  45. What type of filter might be connected to an amateur HF transmitter to cut down on harmonic radiation?
    A. A low pass filter.
    B. A key-click filter.
    C. A high pass filter.
    D. A CW filter.

  46. Why do modern HF transmitters have a built-in low pass filter in their RF output circuit?
    A. To reduce fundamental radiation.
    B. To reduce frequency interference to other amateurs.
    C. To reduce harmonic radiation.
    D. To reduce RF energy below a cut-off point.

  47. What circuit blocks RF energy above and below a certain limit?
    A. A high pass filter.
    B. An input filter.
    C. A low pass filter.
    D. A band pass filter.

  48. What should be the impedance of a low pass filter as compared to the impedance of the transmission line into which it is inserted?
    A. Substantially lower.
    B. Twice the transmission line impedance.
    C. About the same.
    D. Substantially higher.

  49. In order to reduce the harmonic output of a high frequency (HF) transmitter, which of the following filters should be installed at the transmitter?
    A. Band pass.
    B. High pass.
    C. Rejection.
    D. Low pass.

  50. To reduce harmonic output from a transmitter, you put a __________ in the transmission line as close to the transmitter as possible.
    A. high pass filter
    B. low pass filter
    C. band reject filter
    D. wave trap

  51. To reduce energy from an HF transmitter getting into a television set, you would place a _________ as close to the TV as possible.
    A. low pass filter
    B. wave trap
    C. band reject filter
    D. high pass filter

  52. A band pass filter will:
    A. attenuate high frequencies but not low
    B. pass frequencies each side of a band
    C. allow only certain frequencies through
    D. stop frequencies in a certain band

  53. A band reject filter will:
    A. allow only two frequencies through
    B. pass frequencies each side of a band
    C. pass frequencies below 100 MHz
    D. stop frequencies each side of a band

  54. A high pass filter would normally be fitted:
    A. between microphone and speech amplifier
    B. as a Morse key or keying relay in a transmitter
    C. at the antenna terminals of the TV receiver
    D. between transmitter output and feed line

  55. A low pass filter suitable for a high frequency transmitter would:
    A. pass audio frequencies above 3 kHz
    B. attenuate frequencies below 30 MHz
    C. attenuate frequencies above 30 MHz
    D. pass audio frequencies below 3 kHz

  56. What does chirp mean?
    A. A high-pitched tone which is received along with a CW signal.
    B. A small change in a transmitter’s frequency each time it is keyed
    . C. A slow change in transmitter frequency as the circuit warms up.
    D. An overload in the receivers audio circuit when CW is received

  57. What can be done to keep a CW transmitter from chirping?
    A. Add a key-click filter
    B. Keep the power supply voltages very steady.
    C. Keep the power supply currents very steady.
    D. Add a low pass filter.