Sansui AU 11000 Power supply issues

[Johnny JJ]

I have an AU-11000 that I recently acquired. The power supply boards (F-2582 & F-2568) had some fried components that needed replacing. I replaced all the electrolytic caps, diodes and almost all the transistors.
Upon power up the protection works properly and the main amp works but running through the preamp there is no sound. I've also set the bias and offset.
The feed from F-2582 to F-2568 measures 68.9V at terminal 01 and 69.6V at terminal 04.
So I'm assuming F-2582 is ok and focusing on F-2568. The problem is the pre-amp boards are not getting sufficient voltage.
The B+ and B- output from F-2568 read +2.0V on terminal 08 and -2.2V on terminal 05 and 0V on terminal 06. Isolated from downstream they measure 0V on terminal 08 and -4.5V on terminal 05 and -2.0V on terminal 06. I've checked all the resistors, solder points, transistor pin matching, diode biasing and everything seems in order. I'm starting to question my substitutions, especially for the transistors. These are the replacement parts I used:

TR01 (2SD356) = MJE15032G
TR02 (2SB526) = MJE15033G
TR03, TR05, TR08, TR09 (2SC1313) = KSC1815YTA
TR04, TR06 (2SA726) = KSA992FBU
TR07 (2SA733) = KSA733CGBU
TR10 (2SC1364) = KSC2690AYSTU

ZD01. ZD02 (RD39EB) = BZX85C3V9 update: **wrong sub(3.9V)**
ZD03 (RD10EB) = BZX85C10
D01 (1N60) = 1N4148TA
D02, D03, D04 (1S953) = 1N4148
D06 (SV02) = Did not replace, but tests ok

I'm hoping someone can see something that I don't or recommend a solution.

 

[Hyperion]

TR01 (2SD356) = MJE15032G
TR02 (2SA726) = MJE15033G
TR03, TR05, TR08, TR09 (2SC1313) = KSC1815YTA
TR04, TR06 (2SA726) = KSA992FBU
TR07 (2SA733) = KSA733CGBU
TR10 (2SC1364) = KSC2690AYSTU

ZD01. ZD02 (RD39EB) = BZX85C3V9
ZD03 (RD10EB) = BZX85C10
D01 (1N60) = 1N4148TA
D02, D03, D04 (1S953) = 1N4148
D06 (SV02) = Did not replace, but tests ok

Please check the bolded items above.

"ZD01. ZD02 (RD39EB) = BZX85C3V9" - the original zener is 39 Volts - you have quoted the type number of a 3.9 Volt zener.

 

[Johnny JJ]

Please check the bolded items above.

"ZD01. ZD02 (RD39EB) = BZX85C3V9" - the original zener is 39 Volts - you have quoted the type number of a 3.9 Volt zener.

Thanks so much. I missed that. I knew I just needed another set of eyes. I'll let you know how it goes.

 

[Johnny JJ]

I just put the old zeners back in (turns out they were still good). That did the trick! Everything is good.
Thanks again Hyperion (John). Much appreciated

 

[LBPete]

Everybody loves a happy ending. Please post the serial number for the database. Click on the link in my signature block below.

- Pete

 

[Johnny JJ]

Everybody loves a happy ending. Please post the serial number for the database. Click on the link in my signature block below.

- Pete

Sorry Pete I can't make out the S/N sticker on the back, it's mostly rubbed off. All I have is an M.D. & code no. from behind the faceplate

 

[LBPete]

If it's gone, it's gone. They don't all survive. Thanks for looking.

- Pete