(a) Signal voltage chart.
(5) If the
indications obtained in (3)
o r (4)
above are low or absent,
Circuit junction
Signal Voltage (rms)
to h below.
proceed
g. Bandwidth
Test for 47-Mc Amplifier.
P7701-M
81mv
R7703 and c7701
15.55 mv
(1) A d j u s t the 606A for a 411A in-
Q7701 emitter
17.5 mv
dication of 200 mv.
Q7701 collector
1.75 v
(2) Adjust potentiometer R7718 for an
(b) DC voltage chart.
ME-26 B/U indication of +3 volts
dc.
+dc Voltage to
Circuit junction
ground (volts)
(3) Adjust the 606A frequency to 42.00
mc and adjust the output level to
P7701-L
16.0
L7701 and C7702
14.8
maintain a 411A indication of 200
6.95
Q7701 emitter
m v . Record the ME-26B/U indi-
Q7701 base
6.75
cation.
2.9 (rectified
CR7701 and R7708
signal)
(4) Adjust the 606A frequency to 54.00
P7701-J
2.0 (rectified
mc and adjust the output level to
Signal)
maintain a 411A indication of 200
(3) Remove the test signal and set the
m v . Record the ME-26B/U indi-
T S - 1 7 7 7 / V R M - 1 ON-OFF switch
cation.
to OFF.
(5) A normal indication, noted in (3)
(4) Replace the faulty part.
above, should be +1.0 volt dc 0.25.
(5) Repeat b and c above.
(6) A normal indication, noted in (4)
e. P r e p a r a t i o n f o r 4 7 - M c A.m p l i f i e r
above is +1.0 volt dc 0.25.
Tests.
(a) If indications obtained are nor-
(1) S e t T S - 1 7 7 7 / V R M - l s e l e c t o r
mal, trouble isolation in assem-
switch S7 902 to position 18.
bly A7700 is complete.
(2) Adjust the 606A for a frequency of
47.000 mc with an output of 0 volt
(b) If " indications are low, proceed
and connect it to the test probe.
to h below.
(3) C o n n e c t the 411A to connector
h. Trouble Isolation in 47-Mc Amplifier.
P7701-B.
(1) Adjust the 606A for a frequency of
(4) C o n n e c t the ME-26B/U to con-
47.000 mc at a level of 165 mv as
nector P7801-H and adjust to in-
indicated on the 411A.
d i c a t e + volts dc on the W-volt
(2) Measure the listed typical signal
scale.
and dc voltages listed in the charts
f. Gain Test for 47-Mc Amplifier.
b e l o w to isolate the faulty part.
(1) Adjust the 607A output for a 411A
M e a s u r e the ac voltages with an
indication of 200 mv.
M E - 3 0 B / U ; measure the dc volt-
(2) Adjust potentiometer R7718 for a
ages with an ME-26B/U.
m a x i m u m indication on the ME-
(a) Signal voltage chart.
26B/U.
(3) A d j u s t capacitor C7708, trans-
Circuit junction
Signal Voltage (rms)
former T7702, and inductor L6705
I
for a maximum indication on the
P7701-B
165 Mv
M E - 2 6 B / U . A normal indication
Q7702 base
165 mv
Q7702 emitter
should be +3.0 volts dc minimum.
120 mv
Q7702 collector
680 mv
(4) Increase the 606A output to 300
T7702 and C77109
150 mv
mv as indicated on the 411A. A
Q7703 emitter
165 mv
Q7703 collector
normal indication should be +4.0
1.74.V
C7712 and CR7702
1.72 V
volts dc minimum.
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