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. Repeat step 1 and 2 until no further adjustment is necessary.
. Set the generator to 600 KHz,
tune
the receiver to the same frequenty-and adjust aslug
core of AM ferrite rod antenna for maximum output.:
. Set the generator to 1400 KHz and tune the receiver to the same frequency and adjust the
trimming capacitor CA-1 for maximum output.
. Repeat
procedures
4 and 5 until no further adjustment is necessary.
Note:
During tracking alignment reduce the signal generator output as necessary to avoid AGC
action.
9.
FM Alignment Procedure
1.
2
Connect a FM signal generator to the FM antenna terminals and an oscilloscope and an audio
distortion analyzer to the tape output jack on the rear panel.
Set the FM SG to 87.5 MHz and provide about 3 to 5yV. Place the tuning pointer at the low
frequency end by rotating the tuning knob and adjust the core of oscillator coil L108 to
obtain maximum audio output.
. Set the FM SG to 108.5 MHz and provide about 3 to 5uV. Rotate the tuning knob and dbs
the tuning pointer at the high frequency end and adjust the trimming capacitor C152 for
maximum output.
. Repeat
steps 2 and 3 until no further adjustment is necessary.
. Set the FM
SG to 90 MHz and tune the receiver to the same frequency.
Decrease signal
generator output until the audio output level decreases with the decreasing generator output.
Adjust the RF coil L107 and antenna coil L106 and IF transformer L109 for minimum audio
distortion.
. Set the FM SG to 106 MHz and tune the receiver to the same frequency. Decrease the signal
generator output until the audio output level decreases with the decreasing generator output.
Adjust the trimming capacitor CF-1 and CF-2 for minimum distortion.
. Repeat
steps 5 and6
until no further adjustment is necessary.
. Connect
a DC VTVM
with 1 V range selected to the resistor R237 (inside) and adjust the
secondary
core
(black)
of discriminator transformer
L201
so that no voltage reading is
obtained on the VTVM at no signal. Next set the FM SG to 98 MHz. and increase the output
level 1 KuV, then tune the receiver to the same frequency so that no deflection is obtained on
the VTVM. Adjust primary core (pink) of L201 for minimum distortion.
ane.
10. Stereo Separation Alignment
=
=
1.
2.
Set the FM SG to provide
1KuV at 98 MHz. Tune the receiver to the same faddenty so that
the VTVM connected to the Resistor R237 (inside) will give no readings.
Modulate the FM SG with 67 KHz audio frequency. Connect an oscilloscope to the R315.
- Adjust the core of L303 for minimum height of the 67 KHz signal on the scope.
4,
. Modulate the FM SG output with stereo composite signal consisting of subchannel signal only
(of course, a pilot signal must be included). Adjust the core of L304 for maximum
audio
output, then modulate the signal generator output with a stereo composite signal consisting of
L channel signal only and again adjust the core of L304 for maximum audio output.
Adjust the trimming resistor R329 for maximum and same separation in both channels.
11. Muting Threshold Adjustment
1.
Set the FM SG output to provide 12.5uV (IHF) at 98 MHz and tune receiver to the same
frequency. Adjust the trimming resistor R245 for the threshold level of 12.5uV. (During this
adjustment turn the MUTING
pushswitch ''on''.)
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