AA/Rowe 45 rpm phono

Hi All,
I have run into a "situation" that I hope someone else has seen before, cause I'm lazy, and really don't want to spend a lot of time crawling around finding this problem.
This is is one of the last built 45rpm Antique Apparatus, units using Rowe guts--but a "homemade" wiring harness--and they put all "electronics", other then the CCC and MCC in a drawer, accessible only from the rear of the phono--what a pure "PIA" !
Anyway--I am not getting the 8 volts up to the CCC---which of course leaves everything including the display "dark".
TIA for any time saving Ideas--wires are too short to measure anything other then on the MCC-- Ron Rich

Ron:

Check the wires on the service switch. I saw one that had push on quick disconnects and one had come off thus killing power to the CCC.

Thanks, Ken--been that done there--I have seen that several times--
Ron Rich

Hello Ron,

If I remember correctly isn't the power supply part of that draw assembly.

The power supply board is usually the issue check that CR511 ( a 7.5 volt zenor is ok) also CR512 (a 13 volt zenor is ok) check transistors Q503 & Q504 (both MPS A06) the .82 ohm 2 watt resistors can also be an issue check for any cracks or signs of overheating.

Regards
Alan

Alan Hood
ami-man
UK

Hi Alan,
Yes--PSB is sitting right in the left corner of the "drawer". All voltages are good--even swapped board for known,working, one ( also swapped, CCC and MCC)--no 8volt LED on CCC--
Ron

Hi Ron,

Are the two darlingtons on a board somewhere could it be one of these at fault. I know that these drawers are a trial!!!!!! I have only worked on one and had to put the amp parts in a real chassis to get any results.

Regards
Alan

Hi Alan,
The two transistors are right next to the PCB--however, in this case, I know that they are not the fault, as the "sub" board that I used was the newer type switcher--outboard transistors are not used. I did work on one other built like this--also had amp problems, and like you, I had to put the boards in a "regular" chassis in order to set the bias ( at least an "educated guess")-- AA decided to mount the boards "upside down", in the drawer, so that the bias pots can't be turned. Ron Rich

Ron, post pictures of this beast...

Hi John,
Will do, if they guy brings it to me--
Ron