Sparking may be reduced at the contacts of a morse
code key used with a radio-telegraph transmitter by:
  1. buffing the key contact surfaces with light sandpaper 2. use of a good grade cleaning fluid 3. ensuring that the code key is properly grounded 4. use of a capacitor and resistor in parallel with the telegraph key

One possible cause of TV interference by harmonics from a SSB transmitter is from :flat topping" driving the final into non-linear operation. The most appropriate remedy for this is to:
1. reduce microphone gain 2. reduce oscillator output 3. use another antenna 4. retune transmitter output

Television interference caused by harmonics radiated from
an amateur transmitter could be eliminated by fitting:
1. a low pass filter in the TV receiver antenna input 2. a high pass filter in the transmitter output 3. a low pass filter in the transmitter output 4. a band-pass filter in the speech amplifier

A low pass filter suitable for a high frequency amateur transmitter would:
1. attenuate frequencies above 30 Mhz 2. pass audio frequencies below 3khz 3. attenuate frequencies below 30 Mhz 4. pass audio frequencies above 3khz

One of the principle causes of TVI from VHF transmitters operating on 50 Mhz is:
1. co-channel interference 2. cross modulation 3. second harmonics 4. adjacent channel interference on channels 2 and 3

An interfering signal from a transmitter is found to have a
frequency of 57 Mhz (TV ch 2 is 54-60Mhz). This signal could be:
1. seventh harmonic of an 80 metre transmission 2. third harmonic of a 15 metre transmission 3. second harmonic of a 10 metre transmission 4. crystal oscillator operating on its fundamental

Unwanted signals, transmitted by a radio transmitter causing
harmful interference to other users, are known as:
1. rectified signals 2. reradiation signals 3. reflected signals 4. harmonic and spurious signals

When the signal from a transmitter overloads the audio
stages of a broadcast receiver, the transmitted signal:
1. can appear wherever the receiver is tuned 2. appears only when a station is tuned 3. is distorted on voice peaks 4. appears only on one frequency

Cross-modulation of a broadcast receiver by a nearby
transmitter would be noticed in the receiver by:
1. interference continuously across the dial 2. the undesired signal is in the background of the desired signal 3. interference only when a broadcast signal is tuned 4. distortion on transmitted voice peaks

Cross modulation is usually caused by:
1. rectification of strong signals 2. harmonics generated at the transmitter 3. improper filtering in the transmitter 4. lack of receiver sensitivity and selectivity