NZART Amateur Examination                     page 9          NZARTX07 Security code 270029
- To lower the resonant frequency of an antenna, the
operator should:
- lengthen the antenna
- centre feed the antenna with TV ribbon
- shorten the antenna
- ground one end
- A Yagi antenna is said to have a power gain over a
dipole antenna for
the same frequency band because:
- it radiates more power than a dipole
- more powerful transmitters can use it
- it concentrates the radiation in one direction
- it can be used for more than one band
- Because of high absorption levels at frequencies below
4 MHz during
daylight
hours, only high angle signals are normally reflected back by
this layer:
- C
- D
- E
- F
- One of the ionospheric layers splits into two parts during
the day called:
- A & B
- D1 & D2
- E1 & E2
- F1 & F2
- The distance from the transmitter to the nearest point
where the sky wave
returns to the earth is called the:
- angle of radiation
- maximum usable frequency
- skip distance
- skip zone
- If the frequency of a transmitted signal is so high that we
no longer receive
a
reflection from the ionosphere, the signal frequency is above
the:
- speed of light
- sun spot frequency
- skip distance
- maximum usable frequency
- Reception of high frequency radio waves beyond 4000
km normally
occurs by
the:
- ground wave
- skip wave
- surface wave
- sky wave
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