B-006-08: Wavelength vs physical length
B-006-08-01:
If an antenna is made longer, what happens to its resonant frequency?
It decreases
It increases
It stays the same
It disappears
B-006-08-02:
If an antenna is made shorter, what happens to its resonant frequency?
It increases
It stays the same
It disappears
It decreases
B-006-08-03:
The wavelength for a frequency of 25 MHz is:
12 metres (39.4 ft)
15 metres (49.2 ft)
4 metres (13.1 ft)
32 metres (105 ft)
B-006-08-04:
The velocity of propagation of radio frequency energy in free space is:
300 000 kilometres per second
3000 kilometres per second
150 kilometres per second
186 000 kilometres per second
B-006-08-05:
Adding a series inductance to an antenna would:
decrease the resonant frequency
increase the resonant frequency
have little effect
have no change on the resonant frequency
B-006-08-06:
The resonant frequency of an antenna may be increased by:
shortening the radiating element
lowering the radiating element
increasing the height of the radiating element
lengthening the radiating element
B-006-08-07:
The speed of a radio wave:
is the same as the speed of light
is infinite in space
is always less than half speed of light
varies directly with frequency
B-006-08-08:
At the end of suspended antenna wire, insulators are used. These act to:
limit the electrical length of the antenna
increase the effective antenna length
allow the antenna to be more easily held vertically
prevent any loss of radio waves by the antenna
B-006-08-09:
To lower the resonant frequency of an antenna, the operator should:
lengthen it
shorten it
ground one end
centre feed it with TV ribbon feeder
B-006-08-10:
One solution to multiband operation with a shortened radiator is the "trap dipole" or trap vertical. These "traps" are actually:
a coil and capacitor in parallel
large wire-wound resistors
coils wrapped around a ferrite rod
hollow metal cans
B-006-08-11:
The wavelength corresponding to a frequency of 2 MHz is:
150 m (492 ft)
360 m (1181 ft)
1500 m (4921 ft)
30 m (98 ft)
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