C2, TM 11-6625-564-45
capacitor C8 to tripler amplifier Q3.
coupled through C20 to the input of direction-
c. Transitor Q3, tuned for the third har-
al coupler DC1.
monic (300 mc), multiplies the signal and
1-16.1 Uhf Test Generator Module 1A5
couples it through capacitor C14 to tuned
d. Transistor Q4 amplifies the 300 mc and
couples it through capacitor C17 to tuned
The uhf test generator consists of a crystal-
e. Transistor Q5 amplifies the 300-mc
controlled oscillator, a t r i p l e r , a n d f o u r
The setting of VSWR CAL variable
The oscillator produces a
resistor determines the gain of the stage
100-mc cw signal that is multiplied to a
and, thus, the output of the uhf test genera-
300-mc cw signal by the tripler. The ampli-
fiers provide gain and impedance matching
f Transistors QS and Q7 function together
with excellent signal-plus-noise t o n o i s e
to provide an impedance match and cali-
brated 300-mc output signal through capaci-
a. The first stage is a tuned-collector,
tor C36 to directional coupler DC1.
A positive voltage is applied to the collector
of transistor Q1, and the collector circuit
begins to resonate.
The voltage developed
1-17. Directional Coupler DC1
in the collector tank circuit is applied to
voltage divider capacitors C3 and C4.
voltage across C3 is applied to the emitter
The directional coupler consists of a length
tank circuit through crystal Y1, thus pro-
of nominal 50-ohm transmission line con-
ducing a very selective feedback signal to the
This signal is
nected to two permanently adjusted coupler
emitter of transistor Q1.
amplified by transistor Q1 and coupled
assemblies to which meter M1 can be attached
through capacitor C5 to tuned amplifier Q2.
for the reading of forward and reflected
b. Transistor Q2, tuned for 100 mc, am-
The directional coupler samples rf
plifies t h e s i g n a l a n d c o u p l e s i t t h r o u g h
power and converts it to dc power.