10.
Assume that you are required to determine the attenuation of a transmission line. If the input is 60 milliwatts and
the output power is 12 milliwatts, the attenuation is:
a.
5 dB.
c.
12 dB.
b.
7 dB.
d.
48 dB.
11.
A transmission line requiring minimum attenuation is being installed between stations A and B. The type of
transmission line that has the lowest attenuation for a given distance is:
a.
field wire.
c.
five-pair cable.
b.
open-wire line.
d.
spiral-four cable.
12.
Assume that the distortion of a voice-frequency signal in a transmission line is due to the unequal attenuation of
the different frequencies. This distortion, as well as the attenuation, in the line can be reduced by the addition of:
a.
series inductance.
c.
parallel capacitance.
b.
parallel resistance
d.
series resistance.
13.
Inductive coupling (fig. 63) between the conductors of a transmission line may cause crosstalk between adjacent
circuits. One method used to reduce this crosstalk is to:
a.
transpose and balance the capacitance of the lines.
b.
install filters in the lines.
c.
install repeating coils in the lines.
d.
transpose the conductors of the lines.
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