LESSON 4 EXERCISES
In each of the following exercise, select the ONE answer that BEST completes the statement or answers the
question. Indicate your solution by circling the letter opposite the correct answer in the subcourse booklet.
1.
A communication system consisting of teletypewriters connected by a dc signal line is essentially a telegraph
system in which the:
a.
stop pulse need never be transmitted.
b.
first impulse of a code character is always a mark.
c.
line carries no current until the operator starts sending.
d.
receiving teletypewriter automatically translates the coded pulses into words.
2.
A voice-frequency (vf) telegraph terminal operates on the principle that marks and spaces in a teletypewriter
output signal cause:
a.
an oscillator to shift from one frequency to another.
b.
the amplitude to change in a constant-frequency signal.
c.
a tone to pass during the marking interval and disappear during the spacing interval.
d.
the tone to pass during the spacing interval and disappear during the marking interval.
3.
The function of the stop pulse in a character of the Baudot teletypewriter code is to:
a.
signal the end of transmission.
b.
stop the motor when the message is finished.
c.
indicate a momentary pause in the transmission of a message.
d.
synchronize the receiving teletypewriter with the sending teletypewriter.
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