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Does the start sensor pulse at pin (87) 
of IC701 change from "L" to "H" level 
when the cassette tape is loaded?

Check line between start sensor and pin 
(87) of IC701.

Does the end sensor pulse at pin (86) 
of IC701 change from "L" to "H" level 
when the cassette tape is loaded?

Check line between end sensor and pin 
(86) of IC701.

Does the master cam mode shifter 
operate normally when the cassette 
tape is loaded?

Check line between cam switch and 
IC701.

Replace IC701.

Does the capstan motor start when the 
EJECT button is pressed?

See FLOW CHART NO.12. CAPSTAN 
MOTOR TROUBLESHOOTING

Does the take-up reel disk turn when the 
capstan motor is running?

Check line between take-up reel 
sensor and pin(2) of IC701.

Is a "H" level applied at pin(10) of P701 
when a reel pulse has been inputted?

Check line between pin(92) of IC701 
and pin(10) of P701.

Is the supply voltage of 12V fed to 
pin(8) of P701?

Is the voltage about 10V sent out from 
IC on mechanism?

Check IC on mechanism.

Is the specified voltage applied at the 
loading motor terminal?

Check line between IC on mechanism 
and loading motor.

Does the loading motor run?

Replace loading motor.

Replace cassette cam, gear, etc.

Check M 12V lines.

Is the voltage more than about 2.6V 
DC given out of pin(29) of IC701?

Check IC701.

Is the supply voltage of 5V fed to 
pin(3) of P701?

Check PC 5V line.

Is the voltage more than 2.6V DC 
sent in pin(9) of P701?

Check line between pin(9)  of P701
 and pin(29) of IC701.

Is the voltage of pin(5) of P701 is 
1.6~2.7V? 

Check line between the pin(91) of 
IC701 and pin(5) of P701.

Is the supply voltage of 12V/20V fed 
to pin(2) of P701? 

Replace capstan motor.

Check MOTOR Vcc line and motor 
voltage selector circuit.

Is the voltage more than about 2.6V 
DC given out of pin(30) of IC701?

Check IC701.

Is the voltage more than about 2.6V 
DC given out of pin(12) of P701?

Check line between pin(30) of IC701 
and pin(12) of P701.

Is the supply voltage of 12V fed to 
pin(8) of P701?

Replace drum motor.

Check M 12V line.

Replace IC on mechanism.

Check peripheral circuit of IC on 
mechanism

Is drum PG signal given out from the 
pin (11) of P701?

Is drum PG signal fed to pin(65) of 
IC701?

Check line between pin(11) of P701 
and pin(65) of IC701.

Is head switching pulse sent out from 
the pin(23) of IC701?

Check IC701.

Replace IC701.

Check drum motor.

D-FG

D-PG

See FLOW CHART NO.14, 15 (DRUM 
MOTOR TROUBLESHOOTING(1), (2))

Is the drum motor rotating?

Is the drum PG signal and drum FG 
signal present at pin(65) of IC701?

Replace IC701.

Check line between P701 and 
IC701.

Check peripheral circuit of IC on 
mechanism.

Are the drum PG signal and drum FG 
signal present on pin(11) of P701?

2.5V

2.5V

Is the supply voltage of 5V fed to 
pin(37) of IC8001?

Check AT 5V line.

Is the supply voltage of 3.4V, 1.7V 
feed to pin(38) and pin(39) of IC8001?

Check pin(38), (39) of IC8001 
and peripheral circuits.

Is it possible to confirm signals 
LCD RESET, LCD CS, LCD CLOCK
and LCD DATA on the pins(36),
(42), (43) and (44) of IC8001?

Are the segment signals 
supplied to the LCD display 
(LC8001) fromthe driver IC
(IC8001)?

Check peripheral circuit of pin(41) 
of IC8001.

Check that the LCD display is 
free from damages such as 
crack.

Replace IC8001.

Check the signal line between
IC701 and IC8001.

Is the OSC signal at pin(41) of 
IC8001 present?

Check peripheral circuit of X701.

Is there 14.318MHz oscillation at 
pins(37) and (38) of IC701?

Is there drum FG signal at pin(65) of 
IC701 present?

Is the C-SYNC signal(reference) at pin 
(50) of IC701?

Check peripheral circuit of pin(50) of 
IC701, C716, C715 and R708.

Check drum FG signal line.

Is the head switching pulse at pin (23) of 
IC701 present?

See FLOW CHART NO.16
(HEAD SWITCHING PULSE TROUBLE-
SHOOTING.)

Is the drum APC output at pin (34) of 
IC701 and drum AFC output at pin(32) of 
IC701 present?

Replace IC701.

Is the drum control voltage applied to 
pin(12) of P701?

Is pin(30) of IC701 in high impedance?

Check line between pins(34) and (32) of 
IC701 and pin(12) of P701.

Does the IC on mechanism operate 
normally?

Replace IC701.

Replace drum motor.

1

Check "

1

"

Check capstan motor unit and/or replace.

Is there capstan AFC and APC signal at 
pins(31) and (33) of IC701?

Replace A/C head.

Replace IC701.

Is there REC CTL signal output at pins 
(74) and (75) of IC701?

Does PB CTL signal appear at pin (76) of 
IC701?

Does A/C head operate normally?

Adjust the height of the A/C head.

Check the capstan FG signal line between 
pin(1) of P701 and pin(67) of IC701?

Check peripheral circuit at pin(1)  of P701.

Are REC and/or PB mode inoperative?

Check "

2

"

Does pin(29) of IC701 operate normally?

Is there capstan APC  signal at pin (33) 
of IC701?

Does PB CTL signal appear at pin (76) of 
IC701?

Replace IC701.

2

Check peripheral circuit of pin(50) of 
IC701, C716, C715 and R708.

Is the C-SYNC signal(reference) at pin(50) 
of IC701?

Does the capstan FG signal appear at pin 
(67) of IC701?

Check peripheral circuit of X701.

Is there 14.318MHz oscillation at pins(37) 
and (38) of IC701?

A

A

No picture E-E signal. (by pass)

Is picture signal input into the pins(31) and (32) of IC201?

Check the line between pin(24) of TU101 and pin(31) of IC201.
Check the line between external video input terminal (J201) and 
pin(31) of IC201.
Check the line betweem video input terminal and pin(28) of IC201.

Is picture signal outputted to the pin(52) of IC201?

Check the line between pins(63) and (62) of IC201 
and all the way up thru to pins(84) and (85) of IC701.

Is picture signal output to the emitter of video output buffer 
(Q251)?

1

 Line output: Check video output buffer(Q251) peripheral and output terminal periphery.

2

 RF output: Check video output buffer(Q251) peripheral and video input terminal of RF converter periphery.

Is supply voltage of 5V(Y-Vcc) fed to the pin(12) of IC201?

Check the PC 5V line.

Is there Y/C serial data and Y/C signal clock applied 
to the pins(63) and (62) of IC201?

Check peripheral circuit of Q251.