[tig] Ampex DCT 700D Servo/MDA Board help

Stuart stuart
Tue Mar 16 22:05:01 GMT 2004

I have a problem with an Ampex DCT 700D VTR.  Maybe some one can help or 
can give some advice.

The VTR has a problem with the Capstan.  I replaced the Capstan motor 
(it had a bad encoder) but the real problem is probably on the Servo/MDA 
board.  On that board I replaced the MOS FET switching driver (U132) and 
CR42 and CR43  but still have these problems:

1. Motor just gets up to play speed but nothing much faster ( and that 
is only after the VTR has been on for about 10 minutes)  If less then 10 
minutes the recorder is between 50-70% play speed and has a "servo high 
pitched buzz" sound when not at speed.

2. The motor won't go in reverse or rewind.

Does anyone have an extra  SERVO/MDA  board  for this VTR  that I could 
borrow to see if the problem is on this board.
Or I could send my board to you and you could see if it exhibits the 
same problems.
Anyone have an extra SERVO/MDA board for sale?
Any help is appreciated.

Thank You
Stuart Debenham
Debenham Media Group

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