How do I make a 325v power supply for six 12AX7 tubes?

Hello again,

My CL1s-topic is slowing down.
http://www.groupdiy.com/index.php?topic=9951&sid=46ab06f6b9747634612730069a1bfeae

I still need some help on a few things:

I am now sure that there is something wrong with the 350vAC lines from the power transformer. Today I disconnected the two wires coming from the transformer (350v lines). I left the two others (32vAC and 15vAC) connected to the power supply board.

When I power up now the transformer stays cool (not superhot like before). The +15v and -15v output from the board measures +14v and -14v. (Ok?)

The heater and lamp outputs are -12,5v(-) and -33mV(+).

The 325v outputs are of course nothing since I disconnected them.

I have talked to the people at Groove Tubes. They do not have replacement boards or transformers. There has been problems with that power supply. Maybe it would be a good idea to make a separat power board for the 325v?

What I was thinking is that if I put in a second power transformer I could give the board some 350v again?

My question is: would that work? There is space in the box to put in a second torodial transformer if it's not too big.

I need this transformer to feed current for six 12AX7 tubes. Any suggestions?

Thanks in advance.

Richard

BTW, here is a link to the power scematic:
http://home.online.no/~hje-m/cl1s.cfm

woa 2 topics about the same thing.
O.k. so if you are convinced it's a trafo issue replace the trafo. Most of the time GT stuff is nothing more then a rebranded item. could very easily find a replacement... I am suprised that aspin couldn't recomend a replacement trafo...

did you measure the 350v secondary disconnected from the rectifier/regulator?

[quote author="ioaudio"]did you measure the 350v secondary disconnected from the rectifier/regulator?[/quote]

I did that tonight and one end of the secondary was 178vAC the other one 150vAC. That makes 328vAC doesn't it? Well maybe the trafo is ok after all?

One other interesting thing I found. There are two resistors R508 and R509 that are 16k/2W in the schematic but they are 101R/2W on the board. They are in series and are a part of the LM317T adjustment, I think.

Thanks for all your help.

Richard

I have some trouble finding what type of LM317-configuration this is:


Click image for larger view



Richard