AMATEUR RADIO CLASS "A" EXAMINATION
ELEMENT IX
PREPARED BY: HOMER M. ALBUFERA, 4F1KYW


1. The bending of radio waves as they pass over the upper edge of a hill or mountain is known as,

refraction
knife edge diffraction
troposcatter
re-radiation

2. For line of sight propagation, which frequency band is more adaptable?

LF
MF
HF

VHF

3. What type of modulation is largely contained in static and lightning radio waves?

AM
FM
PCM
PM

4. Mobile antennas are of two types; quarter wave ground plane and half-wave type. They are both

parabolic
parasitic
coaxial
vertical-collinear antennas

5. What is the unit of field intensity?

ohms/meter
amperes/meter
watts/meter
volts/meter


6. The ratio of the voltage and current infinite line or a line terminated in its own characteristic impedance

impedance watch
resistance line
characteristic impedance
output impedance

7. Circuit or device that permits transmit and receive operation using one antenna is

diplexer
duplexer
diversity antenna
space antenna

8. A circuit or device that permits two different transmitters to operate with a single antenna,

diplexer

duplexer
diversity antenna
space antenna

9. On what TV channel do the 2nd harmonic of a 27 MHz transmitter fall?

Channel 2
Channel 3
Channel 4
Channel 5

10. A plot of the relative strength or intensity of the antenna radiation as a function of the orientation in a given plane is called

I vs V graph
characteristic curve
radiation pattern
R vs V graph

11.What is the unit of magnetic field intensity?

amperes per meter
volts per meter
amperes per ohm
volts per ohm

12. What is the parameter that compares the concentration of power in the given antenna to that of some reference antenna?

amplification of the antenna
radiation strength of the antenna
propagation of the antenna
gain of the antenna

13. The characteristic of an antenna referring to its capability of beaming, the energy in narrow range of directions is,

selectivity
directivity
sensitivity
accuracy

14. When the electric field lines in a plane parallel to the earth's surface; the polarization is said to be,

vertical
horizontal
circular
perpindicular

15. What is the resistance of free space?

177 ohms
377 ohms
277 ohms
477 ohms

16. The gain in the direction of one of the major lobes of the radiation pattern is known as,

minimum gain
power gain
directivity
directive gain

17. Antenna gains are measured with reference to

parabolic radiator
dipole radiator
directive radiator
isotropic radiator

18. A device used to connect antenna to the output tank circuit of a transmitter in order to prevent the DC supply from reaching the antenna

impedance network
antenna coupler
inductor
oscillator

19. Transmission lines normally used for frequencies above 186 Hz

waveguides
heliax cable
coaxial cable
parallel wire line

20. When the electric field lines in a plane is perpindicular to the earth's surface. the polarization is said to be,

vertical
horizontal
circular
perpindicular

21. What is the wavelength of tje frequency used is 300 MHz,

30 meters
3 meters
1 meter
15 meters


22
. What is the quarter-wave length of 150 MHz?

2 meters
1 meter
0.5 meter
5 meter


23
. What is the approximate height of the geostationary satellite from the earth's surface?

360,000 kms
360,000 miles
36,000 meters
36,000 kms


24
. What is the other name of directing in propagation of radio waves?

bending
tilting
super diffraction
super refraction


25
. What is the speed of electromagnetic waves in free space?

3,000,000 meters/sec
300,000,000 meters/sec
300,000 meters/sec
3,000,000,000 meters/sec


Score = 

Correct answers: