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18.2 AM FREQUENCY RANGE AND TRACKING ALIGNMENT
1. Set an AM signal generator to 515kHz. Turn the tuning capacitor fully closed (with the
tuning pointer placed at the low end.) and adjust the oscillator coil L152 for maximum audio
output.
2. Set the signal generator to 1650kHz. Place |he tuning pointer in the high frequency
end and adjust the oscillator trimmer on the oscillator tuning capacitor for maximum audio
output.
3. Repeat Steps 1 and 2 above until no further adjustment is necessary.
4. Set the signal generator to 600kHz and tune the receiver to the same frequency and
adjust the slug core of the AM ferrite rod antenna and RF coil L151 for maximum output.
5. Set the signal generator to 1400kHz and tune the receiver to the same frequency
and adjust both trimming capacitors of the antenna and RF tuned circuit for maximum
output.
6. Repeat Steps 4 and 5 above until no further adjustment is necessary.
Note: During tracking alignment reduce the signal generator output as necessary to avoid
AGC action.
18.3 AM Signal Strength Meter Adjustment
Set the AM Signal generator to 1000kHz with 5KuV output level, and adjust R178 until
the signal strength meter may read 80%.
19. FM ALIGNMENT PROCEDURES
1. Connect an FM signal generator to the FM ANTENNA terminals and an oscilloscope
and an audio distortion analyzer to the TAPE MONITOR OUT jacks on the rear panel.
2. Set the signal generator to 87.0MHz and provide about 3 to 5uV. Place the tuning
pointer at the low frequency end by turning the tuning knob and adjust the core of the
oscillator coil L105 for maximum audio output.
3. Set the signal generator to 109.0MHz and provide about 3 to 5uV output. Turn the
tuning knob to place the tuning pointer to the high frequency end and adjust the trimming
capacitor C106 for maximum output.
4. Repeat Steps 2 and 3 above until no further adjustment is necessary.
5. Set the signal generator to 90MHz and tune the receiver to the same frequency.
Decrease the signal generator output until the audio output level decreases with decrease
of the signal generator output. Adjust the antenna coil L101, RF coils L102, L103, and
L104, and IF transformer L106 for minimum audio distortion.
6. Set the signal generator to 106MHz and tune the receiver to the same frequency.
Adjust the trimming capacitors (C102, C103, C104, C105) of the antenna and RF tuning
circuits for minimum distortion.
7. Repeat Steps 5 and 6 above until no further adjustment is necessary.
8. Adjust the secondary core (upper) of the discriminator transformer L201 until the
center tuning meter pointer indicates its center with no signal applied. Set the signal
generator to 98MHz and increase its output level to 1kuV and tune the receiver to the same
frequency so that the center tuning meter pointer indicates its center. Adjust the primary
core (lower) of L201 for minimum distortion.
9. Set the signal generator to 98MHz with 100kuV, and adjust R374 until signal strength
meter may read 90%.
19.1 Stereo Separation Alignment
1. Set an FM signal generator to provide 1KuV at 98MHz. Tune the receiver to the
same frequency so that the center tuning meter pointer indicates its center. Then turn
off the modulation of the signal generator, connect a frequency counter to the test point J310
(point ©) and adjust R311 until the frequency counter may precisely read 19kHz.
2. Modulate the signal generator with the stereo composite signal composed of either
Digitized in Heiloo Netherland
5/30/2017
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