16.
Assume that the output of a blocking oscillator is composed of
the desired positive trigger and an undesired negative trigger.
What circuit could be added to the timer to eliminate the
negative triggers?
a.
Peaker.
b.
Clipper.
c.
d.
Overdriven amplifier.
SITUATION.
Assume that the timer shown in Figure 12 is being used to
establish the pulse repetition frequency and develop the gating
voltages of a groundcontrolled approach (GCA) radar set.
Exercises 17 through 19 are based on the above situation.
17.
The blocking oscillator (V6) shown in Figure 12 is used to
develop the transmitter trigger. If the blocking oscillator is
adjusted to produce a pulse repetition frequency of 10,000 Hz,
it will operate in a manner that is best described as
a.
dividing the incoming frequency by three.
b.
reducing the master oscillator frequency by one half.
c.
producing two output triggers for each input trigger.
d.
requiring five input triggers to produce one output trigger.
18.
Cathode followers are used to reduce the loading effects of
components and to
a.
increase the amplitude of the output pulses.
b.
decrease the rise time of the trigger pulse.
c.
provide a lowimpedance output to match cable impedances.
d.
invert or change the polarity of the timer output pulse.
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