Old PSU (PMC Power Mate Corp, UNI-88), scared to burn down house! Pics Incuded

[rwgast_lowlevellogicdesin]

So I was walking the swap meet the other day and I found this old PSU...



its an adjustable linear supply 0-34v, 1.5A. Its pretty old and crusty but for 8 bucks the transformer alone was worth the cost, especially with all those taps. Its based on a 3n3055 power transistor, the build quality inside looks pretty nice, the axial components are sleeved around there leeds, there is what looks like a huge GE cap (maybe oil based) almost half the size of the transformer inside.




I haven't stripped it down any farther than this, I plan to tear it totally down and clean it up after the baby goes to sleep tonight! Ive been wanting to build a digital adjustable voltage supply with current limiting for a while. I figure this could be a good clean linear base supply for the project. All you would have to do is add the current limiting and a micro to this bad boy.

Ive got to say Im a bit worried about plugging it in though. I cant find any manual for it, but from an image search those pins for -out, -sense, +sense, +out, and AC in originally had clips like the ones used to hook up speakers. Thing just had a mains wire shoddily soldered to the AC pins when I bought it, and as you can see in the picture all the DC out and sense pins are soldered togather with a little wire. I originally thought those sense pins were for current, but I dont see any kind of a shunt resistor anywhere near them.

Does anyone know about this psu, have a manual, or can just tell by looking at it what + and - sense do and how they are suppose to be used (i.e read with a meter or something else)? Also this thing looks pretty tough and the parts are pretty good quality from what I can tell, would this make a pretty clean supply? Originally I was going to use a 24v radio shack transformer with some switching regulators to pre track adjustable linear regulators, but if this is a working good quality clean DC power supply i may as well clean it up and use it instead.

[SoundTech-LG]

by any chance, did you mean 2N3055

[Nerull]

So I was walking the swap meet the other day and I found this old PSU...



its an adjustable linear supply 0-34v, 1.5A. Its pretty old and crusty but for 8 bucks the transformer alone was worth the cost, especially with all those taps. Its based on a 3n3055 power transistor, the build quality inside looks pretty nice, the axial components are sleeved around there leeds, there is what looks like a huge GE cap (maybe oil based) almost half the size of the transformer inside.




I haven't stripped it down any farther than this, I plan to tear it totally down and clean it up after the baby goes to sleep tonight! Ive been wanting to build a digital adjustable voltage supply with current limiting for a while. I figure this could be a good clean linear base supply for the project. All you would have to do is add the current limiting and a micro to this bad boy.

Ive got to say Im a bit worried about plugging it in though. I cant find any manual for it, but from an image search those pins for -out, -sense, +sense, +out, and AC in originally had clips like the ones used to hook up speakers. Thing just had a mains wire shoddily soldered to the AC pins when I bought it, and as you can see in the picture all the DC out and sense pins are soldered togather with a little wire. I originally thought those sense pins were for current, but I dont see any kind of a shunt resistor anywhere near them.

Does anyone know about this psu, have a manual, or can just tell by looking at it what + and - sense do and how they are suppose to be used (i.e read with a meter or something else)? Also this thing looks pretty tough and the parts are pretty good quality from what I can tell, would this make a pretty clean supply? Originally I was going to use a 24v radio shack transformer with some switching regulators to pre track adjustable linear regulators, but if this is a working good quality clean DC power supply i may as well clean it up and use it instead.

Sense is almost always used for voltage regulation. That is where the power supply measures its output voltage. Having separate sense terminals allows you to connect sense wires directly to the power input of the DUT and the powersupply will automatically account for voltage drop on the leads. When not being used with sense wires they should be connected to the outputs or the power supply may not regulate at all and some can even be damaged.