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I have a Power Supply with a problem, it keeps cooking a capacitor on the regulator board, and after replacing I can see the voltage drop.
Two questions, what is the IC on the board - LM723 ?? and why is the voltage dropping.

Not a CB question but I'm sure there is place for it on here.
Bob

Th LM723 is the Voltage Regulator IC and I have found these do seem to go bad quite often. They are available from many sources and are inexpensive.

Thanks for the rapid reply, Another source has said it's a LM 324 which is of course an OP AMP.
Thanks again
Bob

DISCOVERED IT WAS NOT A LM723, IN FACT WAS A LM324

Interesting, now I would like to see a schematic of the power supply, perhaps I can find one online.

It just dawned on me, is that a switched mode power supply or does it have a transformer?

timrim,
Did you ever find a schematic diagram for the PSU, as I have a Palstar PS-30M in need of a schematic.
They come under three names that I know of, the Watson, Manson and Palstar.

Dave.

maybe,your on about the transformer ver''5 - 2n3055 on a ali heatsink all hard wired with very short linkings to each other and a pain to get to best i can do these links...

http://home.versatel.nl/bartsimpsons/Ha ... matics.htm

http://www.eham.net/reviews/detail/4064
http://www.nordicpower.se/pdf/MS-EP900.pdf

manson ept-25 =30amp diag not mega fantastic. pdf.

I just repaired one of these recently. The construction of it is really a pain in the arse.

Don't suppose anyone has an ammeter out of one of these?

Thanks for the links, I allready fixed it after replacing all the transistors and fitting sockets for the two IC's and both the IC's while I was in there.
The fault was the 47000uf @35v electrolytic it has a broken terminal.
Now the problem is finding a replacement that'll fit in there.

Dave.

Dave,
You can get the cap from Digi-Key http://uk.digikey.com.
Check D10 known ot go leaky and ZD2.
Not a nice PSU to work on.

Thank's Rick,
I was tempted to give him your name and address to repair it.
I changed the rectifier on this PSU about 5 years ago and fitted lucar connections on the leads so it wasn't that bad to work on.

Dave.