Sony Tape Deck TC FX 420R

[Keith Mills]

I have a Sony tape deck TC FX 420R and am trying to replace the small belt (front) but cannot obtain manual or help from Sony support. The old belt was off when I opened up the deck so I have no idea how to run it.Can anyone show a diagram of how the belt is attached.

 

[73's de Edd]

Sir Keith Mills . . . .

Here ya' go ! . . . . . . and would you like fries with that ?



Belt goes around the large lead capstan flywheel item 158 and around capstan drive motor item M402's wheel / drum.


73's de Edd

 

[Keith Mills]

Thanks Edd for your help but that is the drive belt you showed. It's the other belt a thin round one, I need a diagram for.

 

[73's de Edd]

Sir Keith Mills . . . . . .

Ohhhhh-tay . . . .then.
Cassette installed . . . try fast forward and fast rewind . . . .if no counter action . . .that is being your counter belt.

Informatio Petita . . . .




73's de Edd

 

[Keith Mills]

Thanks for diagram. Replaced belt and deck was working then developed a short somewhere. Now it powers on but not playing. Flywheel doesn't turn. Can any one help me diagnose the faulty part.

 

[73's de Edd]

Sir Keith Mills. . . . .

Initially take DVM and place BLACK probe at marked BLACK square on schematic for ground referencing and then take RED probe and do a DC volts test at the RED triangle to confirm ~13VDC and walk down to the emitter of Q501 to confirm that it is regulating down to ~ 6VDC.

Do the same tests at GREEN triangle to confirm ~ NEGATIVE 13VDC and then move to the emitter of Q503 to confirm that it is regulating down to ~ NEGATIVE 6VDC.

With the unit in play position, confirm ~ 12VDC being across the capstan motor.

Standing by . . . . .



SONY SCHEMATIC SNIPPET . . . .

https://s1.postimg.org/11ojm3xkwd/Sony_Cassete_Deck_III.png



73's de Edd