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Gerowen
03-04-2014, 02:57 AM
Still sorting through the huge pile of stuff I got from this guy, and have a question about this power supply. If anybody knows how to work on these things and can help me out I'd appreciate it.

http://youtu.be/N7Q6inwnctA

mjd420nova
03-05-2014, 11:35 AM
The first thing to look for is the one or two (maybe three) large transistors mounted to the heatsink. These would be the regulators, basically a large high current transistors. They will have some silicone and mica wafer between the heatsink and regulator body. Depending on circuit design you may be able to find the bad one (or more) with a simple diode check otherwise you have to remove them from the circuit to test their condition. Some just use heat sink compound instead of the wafer but both can break down, especially the silcone & wafer combo.

Gerowen
03-05-2014, 07:52 PM
If I put my volt meter on ohms/tone, should I get a tone when touching the posts on the regulators, like I would if I put the posts on either end of a good fuse? I don't, on either of the two.

mjd420nova
03-06-2014, 10:15 AM
Normally, transistor junctions should read conductive one way and open the other way. A transisitor is just a three legged diode. A visual inspection might even reveal some indications of which regulator got hot by looking at the solder joints and the heat sink area for those sighs and chack those suspect ones first. If results are not clear, the reglators will need to be removed from the circuit and chaecked individually.

NY714
05-16-2014, 04:42 AM
In my opinion, the 80 Amp Gold Series is the only good pyramid power supplies. All the other throw out so much RF it get's into you audio and radio and makes sound like shit. The Gold Series of the Pyramid is the only good ones because came with extra protection for RF leakage out of power supply. Presently only new in the Gold Series line being sold is the 80 Amp, that would compare with the best which everyone know is the Astron's.

PS - If you get your hands on some of the older gold series could save money and get a great power supply. Did many testing of power supplies with handheld RF Meters outside to read the Leakage.

Tallman
05-16-2014, 07:10 PM
Still sorting through the huge pile of stuff I got from this guy, and have a question about this power supply. If anybody knows how to work on these things and can help me out I'd appreciate it.

http://youtu.be/N7Q6inwnctA
Where's the video?