[Scott Dorsey]

boardjunkie wrote:
I repaired a G24 for a local studio about 4-5 months back and its down
again with the same problem. The issue is the high current switch for
the take up side reel motor (2SD1047). The one I pulled out was not
shorted, but really leaky. So this makes the third time the same
problem has cropped up.

Anyone else seen this problem? Possible that the motor's on the way
out and pulling too much current? I'm thinking of subbing a little
higher current part for that d1047, but that just may be a band-aid
fix. I didn't check the driver x-istor in front of the 1047for
leakage, just for shorts. Seems like if that was causing a problem it
would've lasted a few days, not a few months.

Could be, I would also lubricate the motor and do a tension adjustment.

I would also make sure that the 2SD1047s that you are getting are
actually good, and they aren't cheap knockoffs. There are a LOT of
semiconductors these days that do not meet original specs.

I'd try both a higher current and a higher voltage part and see how it
goes. I'd also look at the base waveform on a scope and see that it
looks reasonable. I'd also check it in fast forward; it's possible
something is going wrong only in fast forward mode which is why it takes
so long to crop up.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."