Inexpensive Bench Power supply

[smason]

Hi all. I'm wondering if there is a reasonably priced supply out there.
Some of the name brand ones seem very pricy.

I've never really thought I needed one, but lately I'm just annoyed enough at jury-rigging batteries and croc clips, or dragging my Astron RM35 around, that I thought I'd look into it again. Looking for variable voltage/current limit.

I see a few $80.00 ish Chinese units out there. Too crappy?

Any suggestions?

Yes I could build one, but it wouldn't be pretty, and... I'm lazy.

Thanks,

Steve

[etnietering]

Re: Inexpensive Bench Power supply

You might be able to rig up something like this http://www.wikihow.com/Convert-a-Com...b-Power-Supply if you have an extra computer power supply sitting around. You might want to add a high power resistor to both the +12v line and the +3.3v line.

[smason]

Re: Inexpensive Bench Power supply

You might be able to rig up something like this http://www.wikihow.com/Convert-a-Com...b-Power-Supply if you have an extra computer power supply sitting around. You might want to add a high power resistor to both the +12v line and the +3.3v line.

That's a good idea, I have seen it before, however I do want something a bit better. Variable (I do need 6v and 9v occasionally), with meters, and adustable current limiting.

[smason]

Re: Inexpensive Bench Power supply

This one looks tempting:
http://www.dealexcel.com/old/dz-ps30...oduct-430.html

[stj]

Re: Inexpensive Bench Power supply

how much current?

look here:
http://tuxgraphics.org/electronics/

[Krankshaft]

Re: Inexpensive Bench Power supply

I have one of the Chinese ones a Mastech HY3005 looks smiliar to the one stj posted above accept without the HI / LO switch. It's variable up to 30 volts at 5 Amps. It's pretty nice with a white LED backlit display.

The first thing I did of course is replaced the Pyramid SNE brand caps on the secondary and the knockoff Chemicon both on the mainboard and behind the banana output jacks.

Other than that it looks well built the 5 amp model even utilizes a torrid transformer. The 3 amp model utilizes a standard E frame one.

One thing to remember make sure you get a linear and not a switching supply.

The linears cost a bit more but they're worth it. I'm pretty sure the Chinese switchers won't filter out the high frequency noise that well you won't have that problem with a linear.

[smason]

Re: Inexpensive Bench Power supply

how much current?

look here:
http://tuxgraphics.org/electronics/

That's pretty cool. A few interesting things on that site, thanks.

[smason]

Re: Inexpensive Bench Power supply

I have one of the Chinese ones a Mastech HY3005 looks smiliar to the one stj posted above accept without the HI / LO switch. It's variable up to 30 volts at 5 Amps. It's pretty nice with a white LED backlit display..

Cool. Thanks for the info.
I spotted one on Ebay in Canada, so I grabbed it. We'll see how it goes.

[smason]

Re: Inexpensive Bench Power supply

Got it today, looks good, seems to work well. Haven't scoped for ripple yet.

Interestingly, it looks very similar to an Instek branded unit I saw in our local "holy crap that's overpriced" electronics supply place with a $289.00 price tag.