Symptom
Correction
Probable trouble
Defective capacitor or inductor L2
Check parts with appropriate test
10. Output frequency does not coincide
in the frequency determining
equipment. Replace where
with FREQ. IN MEGACYCLES dial
elements of oscillator V5.
necessary.
setting.
Reactor LI defective
Replace LI.
Defective R100, RT2, R66, R65, or
Replace defective component.
C52.
Check alinement of oscillator.
Rf oscillator V5 misalined
Check and, if necessary, replace V3
Defective audio oscillator V3 or am-
11. No audio modulation in output, and
and V4.
plifier V4.
KILOCYCLES DEVIATION meter
Replace El.
Defective El
does not indicate in the 100B, 1600'
Make a voltage and resistance meas-
A defective part in the circuitry of
and 20KC positions of the MODULA-
urement at the tube sockets of V3
V3 or V4.
TION switch.
and V4.
Open arm on DEVIATION cotrol
Replace R15.
R15.
Replace S2.
Open contact on 2
Check contacts on both sections of S2.
Defective contact in a particular
position of the MODULATION
12. No audio modulation in output, and
switch.
KILOCYCLES DEVIATION
Defective part connected to a
meter does not indicate on one of
In 1000' position, check and, if
particular contact of 82.
the three modulation positions of
necessary, replace R23, R26, or CS.
the MODULATION switch.
In 1600' position, check and, if
necessary.replace R22, R25, or C7.
In 20KC position, check and, if necessary,
replace R21, R24, or C6.
Replace SI.
Defective contact on SI
13. KILOCYCLES DEVIATION meter
Replace defective resistor.
Defective resistor in DEV MULT
indicates correctly on all positions
attenuator networks.
of MODULATION switch. There
is no audio modulation in the out-
put on one position of the DEV
MULT switch.
Defective amplifier VI or rectifier V2
Check and, if necessary, repbe VI
14. Audio modulation and deviation
orV2.
normal on all ranges of MODULA-
Defective part in the circuitry of VI
Make a voltage and resistance mess-
TION switch. KILOCYCLES
or V2.
urement at the tube sockets of VI
DEVIATION meter does not indicate
Defective KILOCYCLES DEVIATION
and V2.
meter.
at all.
Replaces MI.
Tube VI 0 or VII in modulator circuit
15. KILOCYCLES DEVIATION meter
Check and, if necessary, replace VI 0
defective.
indicates correctly on all positions
or V11.
A component inthe circuitry of VI 0
of MODULATION switch. There
Make a voltage and resistance meas-
or VII is defective.
is no audio modulation in the out-
urement at the tube sockets of VI 0
C81 shorted
put, very little deviation or excessive
and V11.
Defective V3 or V4
modulation distortion.
Replace C81.
R27 misadjusted. El defective
16. Modulation frequency in output does
Replace defective part.
not coincide with setting of
Realine audio oscillator.
MODULATION switch on all three
positions. Excessive distortion. EXT.
MOD. produces correct output.
17. Modulation frequency in output does
Replace R23 or R26.
In 1000' position, defective R23 or
not coincide with setting of
R26.
Realine C8.
MODULATION switch on one of the
Misadjusted C8
Replace R22 and R25.
three positions.
In 1600' position, defective R22 or
Realine C7.
R25.
Replace R21 or R24.
Misadjusted C7
Realine C6.
In 20KC position, defective R21 or
R24.
Misadjusted C6
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