Sharp VC-S2000HM, Service Manual

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38
VC-S2000HM
FLOW CHART NO.6 TIMER TROUBLESHOOTING (2)
Does the key switch make good contact, when the cassette tape is inserted?
Check switch contact.
Is there the function control voltage inputted at the pins(87) and (88) of IC701, when the keys are activated?
Replace IC701.
Check peripheral circuit of pins(87) and (88) of IC701, and the function keys.
YES
NO NO
YES
Key-in input is not received
<Except for jog shuttle mode
.>
SWITCH
FUNCTION
SWITCH
FUNCTION
SWITCH
FUNCTION
Ref No.
Ref No.
Ref No.
KEY
OFF
KEY
OFF
KEY
OFF
5.0V
S897
REW
(S-VHS ET)
——
———
4.375V
S896
FF
S866
S-VHS ET
——
———
3.75V
S895
REC
S865
TBC/DNR
——
———
3.125V
S894
PLA
Y
S864
TIMER
P801
CASSETTE
2.5V
S893
P
AUSE/STILL
S802
CH(+)
——
———
1.875V
S892
ST
OP
S863
MENU
——
———
1.25V
S861
SET/S.PICT
.
S891
EJECT
——
———
0.625V
S801
CH(-)
S826
ST
ANDBY
P802
TEST
0V
KEY
-1(Pin87 of IC701) KEY
-0(Pin88 of IC701) KEY
-2(Pin82 of IC701)
TERMINAL
VOL
T
AGE
Is the cassette housing distorted?
Fix or replace the cassette housing.
NO
YES YES
YES
YES NO
YES
NO
NO
YES
NO
YES
FLOW CHART NO.8 CASSETTE CONTROL TROUBLESHOOTING(1)
A cassette tape is not take in.
NO
NO
Check start sensor cover.
Check line between start sensor and pin(79) of IC701
Check line between pin(93) of IC701 and pin(11) of IC702. Is the supply voltage of 12V fed to pin(9) of IC702?
Check M 12V lines.
Check IC702.
Check line between IC702 and loading motor.
Replace loading motor.
Is the specified voltage applied at the loading motor terminal when the cassette tape is inserted?
Does pin(13) of IC702 change to about 10V when the cassette tape in inserted?
Does pin(11) of IC702 go to a "H" level when the cassette tape is inserted?
Does pin(79) of IC701 change from "H" to "L" level when the cassette tape is inserted?
Does the start sensor cover go to open when the cassette tape is inserted?
FLOW CHART NO.7 INFRARED R/C TROUBLESHOOTING
No operation is possible from the infrared remote control.
Dose the infrared remote control function?
Replace infrared remote control as required.
Is the supply voltage of 5V fed to C861 of (+) side?
Check AT 5V and GND lines.
Is "L" pulse sent out from pin(1) of the receiver when the infrared remote control is activated?
Replace receiver.
Check between at pin(1) of receiver and all the way up thru to pin(5) of IC701.
Replace IC701.
YES
NO
YES
NO NO NO
YES