Sharp DV-NC55C, Руководство по обслуживанию

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DV-NC55U/C/M
FLOW CHART NO.8
Is the voltage more than about 2.6V DC given out of pin(29) of IC1701.
Check IC1701.
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 pin(4) of AC connector and all the way up thru to pin(29) of IC1701.
Replace capstan motor.
NO NO NO
YES YES YES
Is approx. 3.5V applied to the pin(3) of the AC connector?
Check the pin(92) of IC1701.
NO
YES
Is 23V applied to the pin(5) of the AC connector normally?
Check AT 23V line.
NO
YES
The capstan motor fails to run.
FLOW CHART NO.6 Does the capstan motor start when the EJECT button is pressed?
See FLOW CHART NO.8. <The capstan motor fails to run.>
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 IC1701 when the take-up reel disk is turning?
Check take-up reel sensor and all the way up thru to pin(2) of IC1701.
Replace cassette cam, gear, etc.
NO NO NO
YES YES YES
Is a "H"(about 4.7V) level applied at pin(12) of IC1706 when a reel pules has been inputted?
Check pin(90) of IC1701.
NO
YES
Is the voltage about 10V sent out of pin(15) of IC1706?
Check IC1706.
NO
YES
Is the specified voltage applied at the loading motor terminal?
Check between IC1706 and all the way up thru to the loading motor.
NO
YES
Dose the loading motor run?
Replace loading motor.
NO
YES
The cassette tape fails to eject.
FLOW CHART NO.7 Does power control(H) signal at pin(4) of IC1701 change from "L" to "H" level?
Check IC1701.
Does the base of Q1951 change from about 5.0V to 4.5V?
Check the pin(4) of IC1701 and all the way up thru to Q1952.
Is 5V sent out of the collector of Q1951?
Check Q1951 and the STBY 5V line.
NO NO NO
YES YES
No power is turned on.
FLOW CHART NO.9
Is the voltage more than about 2.6V DC given out of pin(46) of IC1701.
Check IC1701.
Is the supply voltage of 5V feed to pin(3) of IC1706?
Check PC 5V line.
Is the voltage more than about 2.6V applied at pin(2) of IC1706?
Check between pin(46) of IC1701 and all the way up to pin(2) of IC1706.
NO NO NO
YES YES
Is the supply voltage of 12V feed to pin(21) of IC1706?
Check PC 12V line.
NO
YES
Check or replace drum motor.
YES
The drum motor fails to run.
FLOW CHART NO.10
Is drum PG signal given out of pin(7) of IC1706?
Check pins(4), (5), (6) of IC1706 and periperal circuits. Check or replace drum motor. Replace IC1706.
Is drum PG signal given out of pin(66) of IC1701?
Check line between pin(7) of IC1706 and all the way up thru to pin(66) of IC1701.
Is V-H.SW.P pulse given out of pin(23) of IC1701?
Check IC1701.
NO NO NO
YES
YES NO
YES
Replace IC1701.
YES
The drum motor runs only for a few seconds.
FLOW CHART NO.11
Is the drum motor rotating?
See FLOW CHART NO.9, 10 <The drum motor fails to run> <The drum motor runs only for a few seconds>
Is the drum PG signal and drum FG signal present on pins(66) and (65) of IC1701, respectively?
Replace IC1701.
Are the drum PG and drum FG signals present on pins(7) and (8) of IC1706?
Check line between pins(7), (8) of IC1706 and all the way up thru to pins(65), (66) of IC1701.
Check periperal circuit of IC1706.
NO NO NO
YES YES YES
No head switching pulse.
D-FG
About 5Vp-p
D-PG
About 5Vp-p