1. What distinguishing characteristic of a radio system makes it different from a carrier system?
a. Radio uses a carrier frequency below 20,000 Hz.
b. Radio uses a method of modulation different from that used in carrier.
c. Intelligence is separated from the carrier during the demodulation of a radio wave.
d. The carrier used in a radio system is higher in frequency than that used in a carrier system.
2. Low-frequency carriers are usually transmitted over wire or cable facilities because
a. the bandwidth is very large.
b. they will not radiate.
c. they can carry many messages.
d. channel separation is required,
3. One characteristic of a radio communication system is that
a. frequencies have no bearing on distance coverage.
b. a frequency assignment must be made for each RF channel used.
c. it requires less transmitting power than a landline carrier system.
d. there is no danger of power loss due to undesirable radiation from the transmission line.
4. The electrical characteristics of the interconnecting line of a carrier communication system largely
determine the efficiency of transmission. Line loss is due primarily to
a. radiation.
c. attenuation.
b. absorption.
d. intermodulation.
5. The integrated communication system shown in figure 3-1 is built up by starting first with the radio
system and then successively adding
a. telephones, telegraph carrier, teletypewriters, and telephone carrier.
b. telephone carrier, telephones, telegraph carrier, and teletypewriters.
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