Link MST Power Supply

[mbushaw]

Looking for some parts / schematics for the power supplies used in our MST simulator. ADVANCE P1000 outputs of 5V @<hidden> 150A, +-12V @<hidden>, +-15V @<hidden> One of ours blew out the BUX348 transistors (T03 package). I've found the BUX348's available in units of 50, but really seems like overkill when all I need is 2. I've not found a good cross ref, but did try a couple of transistors that had specs that were close, none worked out.
If anyone has some good info on these power supplies, or has found a current substitute for the whole supply or the BUX348 I'd appreciate hearing it.

[woodchopper]

There were a couple guys that fixed those on a regular basis at NWA. They allways talked of replacing output caps, repairing cracked or cold solder joints, and the opto isolators that would fail. One of the supplies was spread out and mounted on a board for easier trouble shooting. If all else failed the parts from the bad supply could be substituted till the bad part was found. Don't know of a source for the parts in question. Hope this helps, good luck.

[mbushaw]

Thanks Woodchopper. Yes, for a power supply they are pretty good as far as being able to quickly swap boards for troubleshooting (that is the only way we were able to confirm it was the the BUX348 transistors).

[simboss12955]

Try these guys...I have always had good luck with them finding old and obsolete parts

http://www.summitelectronics.com

[mbushaw]

Thanks I'll give them a try

[fakeplanefixer]

The sim shop I worked in in Seattle repairs these supplies.

It is very important to Beta match the transistors.

[mbushaw]

Thanks fakeplanefixer. Looks like that's going to have to be the way to go. I've found lots of places that have the transistor I need, but whether you want two or a hundred, the price is $500, and that's just not in my budget this quarter.