11.
In addition to the low input power, the most serious limiting factor to the transmission range of sound-powered
transmitters is the:
a.
lack of amplifying facilities.
b.
poor quality of the transmission media.
c.
poor quality of permanent magnets.
d.
lack of inflexibility of the diaphragms.
12.
The condition of a carbon telephone transmitter can sometimes be determined by measuring its resistance. The
normal value of the resistance should measure approximately:
a.
20 ohms.
c.
100 ohms.
b.
35 ohms.
d.
300 ohms.
13.
The use of the carbon transmitter in place of the original transmitting device used by Bell has greatly increased
the transmitting distance of telephone communication. The current through the carbon transmitter during conversation
can be described as:
a.
an alternating current.
b.
a steady direct current.
c.
a pulsating direct current.
d.
a complex alternating current.
14.
Telephone transmitters generally pick up and transmit undesirable background noises. One transmitter that is
most effective in canceling these noises is the:
a.
positional transmitter.
b.
differential transmitter.
c.
nonpositional transmitter.
d.
nondirectional transmitter.
55