6.
Assume that a change in the tactical situation requires the extension of a 20-mile wire circuit composed of twin-
pair WD-1/TT strung on poles without insulators. By installing insulators, the length of this circuit can be extended to a
maximum of:
a.
40 miles.
c.
60 miles.
b.
50 miles.
d.
70 miles.
7.
The wavelength of a signal is determined by the velocity and the frequency of the signal. For example, the
wavelength of a 1,500-cycle signal over an open-wire line is approximately:
a.
40 miles.
c.
1/40 mile.
b.
120 miles.
d.
1/120 mile.
8.
One of the characteristics of a transmission line is its electrical length. The term electrically short line means that
the length of the line is:
a.
physically 1 mile or less in length.
b.
greater than the transmitted signal wavelength.
c.
equal to the transmitted signal wavelength.
d.
less than the transmitted signal wavelength.
9.
A communications-electronics (C-E) officer constructing a section of open-wire line has two sizes of copper
conductor (104 mils and 128 mils) available for the job. The distributed constant which is the same value for either of the
two conductors is the:
a.
series resistance.
c.
shunt capacitance.
b.
series inductance.
d.
shunt conductance.
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