Pioneer TX-9500II Service Manual page 22

the OFF positions, tum t*re IF tsAND switch
to the NARROW position, and the FUNCTION
switch to the FM AUTO position..
3. Set the semi-variable resistors (VR2 -- VR5 ) of
the AM FM IF assembly to the mechanical
center points, but turn VR1 in the maximum
clockwise direction.
4. Set FM SG to modulation frequency of 400H2,
1007o modulation, and output of 60d8.
5. Tune the dial indicator of TX-9500II and FM
SG to
98MHz (maximum
SIGNAL meter
deflection).
6. Lower the output of the FM SG to a level
(about 10dB) where the SIGNAL meter is no
longer effected by the limiter.
7. Adjust the FM front-end IF TRANS to give
maximum SIGNAL meter deflection.
8. Tum the FM SG output level down until only
the noise level remains, and adjust the core of
T12 to bring the TUNING meter needle to the
center marker.
9. Set the IF BAND switch to the WIDE posi
tion, and the FM SG output level to 60dB.
10. Tune the TX-9500II to 98MHz with the TUN-
ING meter needle at the center marker.
11. Reduce the FM SG output down to a level
(about 20 - 30dB) where the DC voltmeter is
A M F M l F a s s e m b l y
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no longer effected by the limiter (point just
below where any increase in FM SG output
stops producing a change in DC voltmeter
reading.).
12. Adjust the cores of T1 to T5 until the DC volt-
meter gives maximum reading.
13. Return the FM SG output level to 60dB, and
adjust the cores of T11, Tro, Tr, Tr, and T,
consecutively in this order to reduce distortion
to a minimum use a distortion meter for this
measurement. Repeat the process until the
minimum is reached. Then adjust further with
V R r .
14. Set the FM SG output to 80dB, and then
adjust VR3 so that the SIGNAL meter reads
4.8 on the scale.
15. Reset the FM SG output to 50dB, and adjust
(by VRr ) the SIGNAL meter to read 4.
16. Repeat steps 14 and 15 until the required
SIGNAL meter readings are attained.
17. Set the FM SG output to 14dB, and tum the
MUTING switch to position 1.
18. Adjust VRa to the point where the muting
circuit is activated.
19. Reset the FM SG output to 29dB, and turn the
MUTING switch to position 2.
20. Adjust VR5 to the point where the muting cir-
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