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2-28. Synchronous teletypewriter systems are
characterized by which of the following
features when compared to asynchronous
systems?
1. Internal timing signals are always
used
2. Only the start-stop element must be
transmitted
3. Only the intelligence elements must
be transmitted
4. Signal quality determines receiver
line signal condition
2-29. When you are referring to the unit of
teletypewriter signaling speed, the
reciprocal of the time (in seconds) of the
shortest signal element is described by
which of the following terms?
1. Unit code
2. Baud rate
3. Bits per second
4. Words per minute
2-30. The teletypewriter condition where
current flow represents a mark and no
current flow represents a space occurs in
which of the following types of
operation?
1. Polar
2. Arctic
3. Biased
4. Neutral
2-31. You are using neutral keying and the
teletypewriter type hammer continually
strikes the type box but there is no
printing or type box movement across the
page. What is the name of this
condition?
1. Debugging
2. Running open
3. Baudot blanking
4. Decoding at random
2-32. Of the following equipment which one
changes teletypewriter dc pulses to mark
and space modulation for the transmitter
carrier wave?
1. A comparator
2. A modulator
3. A converter
4. A keyer
2-33. To change an rf signal to do pulses for
teletypewriter operation, you must use a
receiver and what other piece of
equipment?
1. A keyer
2. A converter
3. A comparator
4. A demodulator
2-34. A tone-modulated radio teletypewriter
system uses what modulation method to
change dc mark and space impulses into
audio electrical impulses?
1. Amplitude
2. Frequency
3. Phase
4. Pulse
2-35. In a basic tone-modulated radio
teletypewriter system, separation of the
audio signal from the carrier is
accomplished by what process?
1. Conversion
2. Modulation
3. Selection
4. Detection
2-36. In a radio-frequency-carrier shift system,
what equipment is the source of radio-
frequency excitation voltages?
1. The inverter
2. The converter
3. The comparator
4. The transmitter keyer
