Pioneer SX-3700 Service Manual page 19

8 . 3 I D L E C U R R E N T A D J U S T M E N T
1. Turn the VOLUME control down to minimum
level, turn the power on, and wait about 10
minutes.
2. Connect a DC voltmeter to the TP terminals
(L ch; TP48 + and 49 Pin R ch; TP47 +
and TP46 ) of the GWM-159.
3. Check that the voltage between 49 Pin and
TP48 (L ch) lies within the DC 2.2mV-100mV
range. Then make a similar check for the R ch
between "1P47 and TP46. If the voltage is less
than 2.2mY, cut jumper A (L ch), and jumper B
(R ch). If the voltage exceeds 100mV, check for
circuit failure.
8 . 4 F L I N D I C A T O R C I R C U I T
F requency Display Circuit
The offset switching circuit
is employed in
PD5009 AM/FM band selection and FM IF offset.
If cuts are made as directed in the table 2, the level
of each pin in PD5009 will be switched to the
mode indicated in Table 1 on page g.
F M c € r a m i c
f i l t € r
0 1 1
412
R 1 2 1 o k O
O p€n
B l u e
T h e j u m p e r b e t w e e n c o l l e c t o r a n d
e m i t t e r i s t o b e l e f t o p e n .
R 1 2 1 0 k n
Open
Orange
T h € j u m p e r b e t w e e n c o l l e c t o r a n d
e m i t t e r i s t o b e l e f t o p e n .
Table 2
s)<-37clCl
. If
the
SX-3700 frequency display reads
97.95MH2 or 98.05MH2 when a 98.00MH2
signal is applied to the receiver, adjust TC1 so
that the display reads 98.00MH2 correctly.
. If an accurate 98.00MH2 input signal source is
not available, tune the receive to the nearest
known broadcasting station in the 98MHz re-
gion, and check that the station's frequency is
correctly displayed, adjusting TC1 if necessary.
Output Power Indicator Calibration
1. Apply a lkHz signal to the AUX terminals.
2. Adjust the level of this input signal so that the
voltage on the output terminals (SPEAKERS)
read 8.95V (AC).
3. Adjust VR1(L) and VR2(R) so that the out-
put power indicator read 10 watts.
vR2R ip47
Fig. 8-4 Adjusrment point