Service manual

44
13VT-N100
13VT-N150
13VT-CN10
TAKE-UP REEL PULSE GENERATOR TROUBLESHOOTING
FLOW CHART NO.1-7
HEAD SWITCHING PULSE TROUBLESHOOTING FLOW CHART NO.1-8
FLOW CHART NO.1-9
No reel sensor pulse appears.
No head switching pulse.
YES
NO NO
NO NO
NO
YES YES YES
Check the AT12V line.
Insert the cassette, and put the unit in FF or REW mode.
Replace the take up/supply reel sensors D7702/D7703. Check the harness AD- ME and the drum motor unit.
Check pin (18) of IC2001 and signal line of head switching pulse. Check all the way up to pins (89) and (90) of IC2001.
Check between the ME socket and pin (77) of IC2001, and between the ME socket and pin (84) of IC2001.
YES
YES
YES NO
NO NO
DRUM MOTOR TROUBLESHOOTING
The drum motor fails to run.
Is the voltage more than about 2.6V applied at pin (1) of ME connector.
Check between the ME connector and all the way up to pin (90) of IC2001.
Is 5V at pin (7) of ME connector?
Check/replace the drum motor.
Is 12V at pin (4) of ME connector?
Check the AT 5V line.
NO NO NO
YES YES YES
Check or replace IC2001.
The drum motor runs only for a few seconds.
Check pin (84) of IC2001.
Check the drum motor.
Are there the take up/supply reel pulses at the collectors of D7702/D7703. Are the drum PG and drum FG signal inputted to pins (90) and (89) of IC2001, respectively? Are there the drum PG and drum FG Signals at pins (3) and (5) of connector AD?
Check between D7702 and pin (80) of IC2001, between D7703 and pin (79) of IC2001.
Is the drum motor rotating?
Is drum PG signal at pin (90) of IC2001?
Is drum PG signal at pin (5) of ME connector?
Is H.SW. pulse at pin (18) of IC2001?
See FLOW CHART NO. 1-9.
4.2
4.4
0
0
D-PG D-FG
about 4.5Vp-p