6.
The transmitter shown in Figure 65 uses two pulse transformers to
transfer the modulator pulse to the magnetron. The reason for using a
bifilar secondary winding on T2 is to
a.
permit a 4:1 step-up of voltage.
b.
allow the use of a conventional filament transformer.
c.
reduce the effects of the changing magnetron impedance.
d.
permit the use of a smaller pulse cable with less high-voltage
insulation.
7.
The performance of a high-level modulator can be improved by coupling
the pulse from the modulator to the magnetron through a pulse
transformer.
In addition, the use of a pulse transformer has the
advantage of
a.
eliminating the magnetron filament transformer.
b.
permitting higher voltages in the pulse-forming network.
c.
reducing the
potential
between
cathode
and
ground
of
the
magnetron.
d.
eliminating the need for long transmission lines between the
transmitter and the antenna.
8.
If the characteristic resistance of the PFN shown in Figure 65 is not
equal to the magnetron's impedance, the pulse applied to the magnetron
will be distorted. This impedance mismatch will also cause the PFN to
a.
charge to a lower voltage on each succeeding charge cycle.
b.
charge to a higher voltage on each succeeding charge cycle.
c.
produce a pulse that has a duration time of less than two TDs.
d.
produce a voltage
that
will
cause
the
thyratron
to
conduct
prematurely.
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