indec

I'm just getting started with electronics again, and my last dabblings were back in my school days when all the benchtop kit was provided.

The first thing I seem to be needing is a power supply! Can anyone recommend a decent power supply (running off US mains voltage)? I'm looking for variable voltage up to maybe 15V. I don't expect to be nice much in the way of high power work, but then expectations change

I've seen some links to DIY schematics posted in other threads, which I'd consider building, but I'd rather start with a reliable one I can buy if possible. That said, I'd rather not have to go out and spend huge amounts of money either....

mneary

If you have a good general idea of what you want, try www.mpja.com.

mneary

Another suggestion. This one's a kit for $25.

Hank Fletcher

You could also recycle a computer PSU and modify it for your bench supply, provided you're not too fussy about getting exactly 15V. Try searching this forum for "computer power supply" and variations thereof - the mod was easier than I anticipated.

Krumlink

You can make your own, which I tried to but my EE friend gave me a $50 dollar regulated 13.8V PSU

Take a good transformer with a voltage output of around 20 or enough to power the max DC voltage you want.

Then make a bridge rectifier using 1N4004 (I recieved 500 for FREE so I use those always)

Put a large cap across the + and - terminal so it smoothes it out.

Put a bunch of V regs on it (3.3, 5, 8 or 9, 12) and make sure you throw a bunch of caps on the whole thing.

Add a fuse here and there to protect over amping the thing

There you go it should work in theory

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MechTronics

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RadioRon

I recommend starting with a good benchtop supply that you can count on. If you build your own it may function ok, but will it have voltmeter and ammeter, will it have multiple outputs, will it have current limiting and constant current modes? These are valuable features in my opinion. For my bench, I bought surplus DC power supplies wherever I could (ebay, dovebid, local companies etc.) in brands like Hewlett Packard and Fluke/Philips. Have a look on Ebay for Mastech brand supplies, they seem like very good value. I see one that is a triple output (3 different DC supplies in one), 30V/3A with all the good features for only $168. That's quite good if the unit is reliable. Perhaps others can chime in on reliability of this brand.

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RadioRon

Leftyretro

I too have been very happy with used E-bay commerical quality bench supplies. The orginal costs of these were usually well in the 4 digit $$ range. HP and Power design are what I currently own. Lots of high end features and very hard to damage.

Lefty

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speakerguy79

How is the Mastech stuff on Ebay?