Figure 25.
Comparing Characteristics of ATL and
Real Transmission Line.
7.
Radar systems need rectangular pulses.
The magnetron, under the control of the modulator, generates short,
regularly spaced pulses of RF energy. The modulator controls the operation
of the magnetron by supplying it with high-voltage, rectangular pulses of
DC. That is, the modulator controls the shape and duration of the pulses.
The accuracy of the radar set depends on the shape of these pulses. We need
the rectangular pulses that have constant amplitude and steep edges. The
amplitude of the pulse must be constant to keep the magnetron oscillating at
its assigned frequency and correct power output.
The leading edge of the
pulse must be as steep as possible for accurate ranging. The trailing edge
must also be steep to ensure minimum range determination.
8.
ATL produce pulses used in radar.
a. An ATL can produce a nearly rectangular pulse having an amplitude of
several thousand volts.
A multivibrator that could give the same output
would weigh a hundred pounds or more and occupy considerable space.
The
ATL, of course, consists of only a few inductors and capacitors and takes up
much less space. Another advantage is the accuracy with which the amplitude
and duration of the pulse can be delivered.
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