Fm Section - Pioneer sx-450 Service Manual

9 . 2 F M S E C T I O N
1. Through 300 ohm dummy antenna, connect
FM signal generator to the 300 ohm FM
antenna terminals and set for 4OOHz at 100dB
and IO0% modulation.
2. Connect AC voltmeter and distortion meter to
TAPE REC jack (L or R).
3. Set FUNCTION switch to FM and MUTING
switch to OFF.
4. Set FM signal generator and SX-450 dial
indication to point A (90MHz).
5. Adjust T3 for maximum indication on AC
voltmeter.
6. Adjust T5 lower core for center of scale
indication on AM/FM meter.
7. Set FM signal generator for 9dB output and
adjust T1 and T2 for maximum indication on
AC voltmeter.
8. Set FM signal generator and SX-450 dial
indication to point C (106MHz).
9. Adjust TC3, then TC1 and TC2 for *u"i*rr-
A | /
indication on AC voltmeter.
10. Again set FM signal generator and SX-450 dial
indication to point A.
11. Adjust T3, then T1 and T2 for maximum
indication on AC voltmeter.
12. Repeat steps 8-11 to eliminate variations in
sensitivity at points A and C.
13. Adjust "t4 for maximum sensitivity.
14. Detune to noise only and adjust T5 lower core
for center of scale indication on FM meter.
15. Set SX-450 dial indication to point B (98MHz)
and adjust FM signal generator for center of
scale indication on AM/FM meter.
16. Set FM signal generator output to 60dB and
adjust T5 upper core for minimum distortion.
17. Repeat steps 14-16 eliminate variation in mini- J" 'a
mum distortion position.
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