CHAPTER 4 (1-53)

1. Which of the following choices below is the primary purpose of a dummy load?

• a. to prevent the radiation of signals when making tests
• b. to prevent over-modulation of your transmitter
• c. to improve the radiation from your antenna
• d. to improve the signal to noise ratio of your receiver

2. Applying RF energy to the elements of an antenna results in what phase relationship voltage and current?

• a. voltage lags current by 90 degrees
• b. voltage leads current by 90 degrees
• c. voltage and current are 180 degrees out of phase
• d. voltage and current are in phase

3. Which beam width represents the best antenna directivity?

• a. 7
• c. 19
• b. 12
• d. 28

4. The addition of parasitic elements to the Yagi antenna has which of the effects on antenna characteristics?

• a. increased gain
• b. narrower beam width
• c. narrower frequency response
• d. each of the above

5. In trap antenna, if the operating frequency is below that of a trap resonance, the trap behaves as a/n:

• a. series resonant circuit
• b. parallel resonant circuit
• c. inductor
• d. capacitor

6. The polarity of a radio wave is determined by the orientation of (a) what moving field with respect to (b) what reference?

• a. (a) electric (b) earth
• b. (a) electric (b) antenna
• c. (a) magnetic (b) antenna
• d. (a) magnetic (b) earth

7. What does "antenna front-to-back ratio" mean in reference to a Yagi antenna?

• a. the relative position of the driven element with respect to the reflectors and directors
• b. the power radiated in the major radiation lobe compared to the power radiated in exactly the opposite direction
• c. lobe compared to the power radiated 90 degrees away from that direction
• d. the number of directors versus the number of reflectors

8. It is ideally suited to HF transmission and reception and is very popular antenna in commercial point-to-point communications.

• a. Long single-wire antenna
• b. rhombic antenna
• c. fishbone antenna
• d. beverage antenna

9. The front-to-back ratio of a half-wave dipole antenna is:

• a. 0dB
• c. 10 dB
• b. 3 dB
• d. infinite

10. radiated from an antenna is considered horizontally polarized under which of the following conditions?

• a. if the wavefront is in the horizontal plane
• b. if the magnetic field is in the horizontal plane
• c. if the electric field is in the horizontal plane
• d. if the induction field is in the horizontal plane