41
VC-A422U
VC-H822U
FLOW CHART NO.9
The cassette tape fails to eject.
Does the capstan motor start when
the EJECT button is pressed?
See
FLOW CHART NO.12.
Does the take-up reel disk turn when
the capstan motor is running?
Check reel disk and reel drive unit.
Are pulses applied at pin(2) of IC701
when the take-up reel disk is turning?
Check take-up reel sensor and all the
way up thru to IC701.
Is a "H"(about 4.7V) level applied at
pin(12) of IC706 when a reel pules
has been inputted?
Check pin(90) of IC701.
Is the voltage about 10V sent out of
pin(15) of IC706?
Check IC706.
Is the specified voltage applied at the
loading motor terminal?
Check between IC706 and all the
way up thru to the loading motor.
Does the loading motor run?
Replace loading motor.
Replace cassette cam, gear, etc.
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
YES
YES
YES
NO
NO
NO
FLOW CHART NO.10
No power is turned on.
Does power control(H) signal at
pin(95) of IC701 change from "L" to
"H" level?
Check IC701.
Does the base of Q951 change from
about 5.0V to 4.5V?
Check IC701 and all the way up thru
to Q951.
Is 5V sent out of the emitter of
Q951?
Check Q951 and the AT 5V line.
Check peripheral circuits for poor
soldering.
FLOW CHART NO.11
The capstan motor fails to run.
Is the voltage more than 2.6V DC
given out of pin(29) of IC701.
Check IC701.
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
Is the supply voltage of 5V feed to
pin(8) of AC connector?
Check PC 5V line.
Is the voltage more than 2.6V DC
sent in pin(4) of AC connector?
Check between the AC connector
and all the way up thru to pin(29)
of IC701.
Is the voltage at pin(3) of AC
connector about 3.5V?
Check between the pin(92) of IC701
and all the way up thru to pin(3) of
AC connector.
Is the supply voltage of 23V feed to
pin(5) of AC connector?
Check AT 23V line and motor voltage
selector circuit.
Replace capstan motor.
Summary of Contents for VC-A422U
Page 51: ...VC A422U VC H822U VC A422U VC H822U 52 53 SIGNAL FLOW BLOCK DIAGRAM VC A422U ...
Page 52: ...VC A422U VC H822U VC A422U VC H822U 54 55 SIGNAL FLOW BLOCK DIAGRAM VC H822U ...
Page 53: ...56 VC A422U VC H822U POWER CIRCUIT BLOCK DIAGRAM ...
Page 63: ...72 VC A422U VC H822U M E M O ...
Page 76: ...85 VC A422U VC H822U M E M O ...