Sharp VC-384N Serviceanleitung Seite 18

AUDIO CIRCUIT ADJUSTMENT
Output Select Switch
Operational mode of IC6605 is switched by a signal
output from the Speech Output Selector on the front
panel. When the Selector remains in the CH] + CH2
position, the Audio Head outputs both the RCH and
LCH signals. At this time, RF Output sends out a speech
signal REE) . When the Selector remains in either the
CHI or CH? position, only the LCH and RCH signals
are output from the Audio Line and RF Speech Signal
Output.
Perform switching of the Output Select Switch only
when playing back a bilingual tape. Except for the bilin-
gual mode, operate the switch in the CH1 + CH2 posi-
tion.
Y) BIAS
FREQENCY
To01 ABJ
DUNTKO903HE
Bo [_] BH[
R606 © LCH EE LEVEL
BJ
(C601
(C603 TP6O2 LCH
SO REC LEVEL
BA 1602 hers
LCHREC BIAS Sas
01
@) R622 LCH PB1
R602
ied eg
BF ® EE LEVEL
R656 RCH
| REC LEVEL
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IC653 R664 iceso
ae, TP652
BB TP651
—-—-———
RCH IC652
qa REC BIAS @) R652
R653 RCH P8 LEVEL
1) Playbak level adjustment
(A)
1. Play back adjustment the alignment tape (400Hz,
120nwb/m? dolby tape).
2. Connect VTVM to TP6601.
3. Adjust R602 so that the output level become
-2.5dBs.
(B)
1. Play back adjustment the alignment tape (400 Hz,
120nwb/m/m dolby tape).
2. Connect VTVM to TP6602.
3. Adjust R652 so that the out put level become
~2.5dBs.
2) Bias frequency adjustment
1. Select record mode.
2. Connect a frequency counter to AE HEAD.
3. Adjust T601 so that the couter reads 70kHz.
3) Check of erase voltage higher than SOVp-p.
1. Select record mode.
2. Connect an osciloscope to AE HEAD.
3. Check that the erase voltage is higher than SOVp-p.
YA DUNTKOSO4HE \
E> =
BP
BN
1C6605
IC6601