IF UNIT ALIGNMENT
S-Meter Sensitivity Adjustment
1 .
Set the BAND swit ch to 20 meters, the main
dial to 1 4 . 2 5 0 MHz, and set the RF GAIN
fully clo ckwise.
2 .
Set the signal generator t o 1 4 . 2 5 0 MHz, and
set its output to 6 dB . Tune the signal
generator signal on the receiver, and peak the
preselector for m aximum signal strength. The
S-m eter should just b egin to move with the
6 dB input.
3 .
Adjust VR403 for a reading of 0 on the S
meter.
4.
Set the generator output to 1 00 dB, and
adjust VR405 for a reading of S9 + 60 dB on
the S-meter. Confirm that the presele ctor is
peaked.
5 .
Return the signal generator output t o 6 dB,
and recheck the adjustment of V R403
Variable IF Bandwidth Alignment
1 .
Set the controls as follows :
BAND . . . . . . . . 20 m
DIAL . . . . . . . . 1 4 . 200 MHz
RF GAIN . . . . . Fully clockwise
WIDTH swit ch . . OFF
MODE . . . . . . . . USB
Peak the preselector for m aximum response
against the marker signal or background noise .
2 .
Connect the frequen cy counter to TP4 1 1 .
Adjust VR1 s o 1 for a reading of exactly
1 9 . 7 4 7 5 MHz.
3 .
Place the WIDTH swit ch ON. Make sure that
the WI DTH control is exactly in the 1 2
o ' clock position . Adjust VR404 for a reading
of exactly 1 9 . 7 4 7 5 MHz on the frequency
counter.
4 .
Switch between USB and LSB, and observe
the background noise. If there is any dif-
ference , adjust Y R 1 so 1
noise i s the same.
ALC Meter Alignment
until the background
1 .
On any b and, set the MODE swit ch to USB.
Set the meter swit ch to ALC.
2 .
With no speech input , activate the transmitter.
Adjust V R40 1 for a 0 reading on the ALC
m eter scale .
BAND WIDTH
V R 1 5 0 1
CONTROL UNIT
(PB- 1 972)
RECTIFIER B UNIT
Bias Adjustment
1 .
Set the MODE swit ch to USB or LSB , and set
the M IC GAIN control fully counterclockwise.
2 .
Place the M ETER swit ch in the IC position,
and set the VOX GAIN control t o VOX.
Adjust the rear apron B IAS control, V R 1 00 1 ,
for a reading of 5 0 mA. For 1 0 watt m odels,
the corre ct meter reading is 2 5 mA.
V R 1 0 0 1
R E C T . B U N I T ( P B - 1 9 6 8 )
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