Sub-$50 bench power supply?

[guzziguy]

I'm looking to get an inexpensive bench power supply, hopefully for less than $50. Can anybody recommend one. If not, please recommend the least expensive ps that will do the job. Thanks.

[Pars]

Take a look at ebay for starters. I have a dual supply B&K that is OK (and was pretty cheap). I would recommend a dual output supply because many tasks require +/-V. Current limiting would be nice, but for $50 not likely.

Here's an HP that although it seems to need some work, is advertised as working, and not one of these "I'm a test equipment vendor, but this is sold as is cuz I have no way of testing it".

HP 6253A Dual DC Power Supply 0-20V 0-3 Amp - eBay (item 280435088410 end time Dec-13-09 18:00:43 PST)

Drawback is only up to 20V. You can put these in series to get 40V though.

[guzziguy]

Thanks for the pointer. Unfortunately the real drawback with that auction is the $49 shipping cost.

[Pars]

Sorry, hadn't noticed that. Here's a single HP

HEWLETT hp PACKARD DC POWER SUPPLY BENCH SERIES 6218A - eBay (item 300374779932 end time Dec-12-09 16:48:33 PST)

A bit outside your budget:

Hewlett Packard HP 6228B Dual DC Power Supply w/manual - eBay (item 360214245044 end time Dec-10-09 10:30:57 PST)

Lambda:

Lambda LPD-421A-FM Dual 0-20V 1.7A DC Power Supply - eBay (item 360214381205 end time Dec-10-09 18:06:48 PST)

Another HP:

HP 6205B Dual DC Power Supply..... - eBay (item 110468187695 end time Dec-16-09 10:17:12 PST)

[guzziguy]

No problem. I was pretty sure you didn't see it. Obviously the seller is trying to make an extra $30 on the sale.

How does this kit look to you? It doesn't have meters, but it looks pretty useful for only slightly more than my $50 limit.

Edited December 10, 2009 by guzziguy

[Pars]

That kit looks OK, but doesn't have meters (though I don't know that I trust them anyhow), and isn't tracking.

You might take a look at Circuit Specialists and also wait to see if luvdunhill or cetoole or nate or anyone else has recommendations. I seem to recall someone pointing out a new bench supply that looked pretty good, but don't recall what it was.

Circuit Specialists Inc. - Bench Top Power Supplies

[guzziguy]

Thanks. Yes, I was planning on getting more input. I would put this on an Xmas list for my family and won't ask them to spend more than $50 or so. If I have to buy it, I wouldn't hesitate to raise the budget a bit.

Thanks for your help. In the meantime, the two 9V batteries in series will do the job.

[Fitz]

No problem. I was pretty sure you didn't see it. Obviously the seller is trying to make an extra $30 on the sale.

Actually I figure they're only making $8 on shipping... the ebay listing calculates it at $28.12 for me, and the UPS site calculates it at $20.12 (using their given 30lb ship weight, unit itself weighs 28lbs according to HP). And sending 30lbs cross-country via UPS ground will easily cost over $40. Ya wants the big HP tanks, ya pays the big shipping rates.

What're you planning to use it for? A lot of the cost will vary depending on number of rails, maximum output voltage/current, etc.

[guzziguy]

Hey Fitz. How are you doing? Hope things are going well.

I'm looking at it as a beginning DIY tool. What would you suggest are the minimum features I need?

[luvdunhill]

Ken, I'd check out MPJA (MPJA - Power Supply, Power Supplies, Security Cameras, LCD, Fans, Etc.)

[The Monkey]

Ken, whatcha building?

[909]

another $50 price point thread courtesy of ken

[n_maher]

The suggestions in this thread are excellent and I have little to add to that. All I'd suggest is hunting craigslist locally to see if you can't find something that you wouldn't have to ship since these things tend to be on the heavier side.

[guzziguy]

Thanks everybody for your responses.

Ken, whatcha building?

This.

another $50 price point thread courtesy of ken

Yep. I was planning to put it on my Xmas list and I'm trying to limit the cost of buying me gifts.

The suggestions in this thread are excellent and I have little to add to that. All I'd suggest is hunting craigslist locally to see if you can't find something that you wouldn't have to ship since these things tend to be on the heavier side.

Thanks. I see this doesn't belong on a Xmas list. I'll check craigslist. Does anybody have any experience with the kit that I mentioned early in the thread? If not, I may have to take one for the team.

[luvdunhill]

Thanks. I see this doesn't belong on a Xmas list.

3-12V @ 2A BENCHTOP POWER SUPPLY-MPJA, Inc.

$20?

[guzziguy]

Looks good for an entry level P/S. It's out of stock at the moment, but I'll look again later if I don't get the kit for Xmas.

[CarlSeibert]

I think I got a flyer from Parts Express this week or last with a similar one for $12.

[mypasswordis]

guzziguy, if you are going to be DIYing a bunch of stuff after this, it may be a good idea to get a power supply that isn't so limited, which will save you money in the long run. I realize this is way over budget but looks like something I might buy in the future unless I find something better/cheaper:

0-50V @ 3A BENCH POWER SUPPLY-MPJA, Inc.

Meanwhile it's time for me to pick up my new soldering station.

[grenert]

I think one nice thing about the kit you linked to is that it is a dual supply. There are a lot of times when you'll need both + and - rails.

If you decide to go with a fancier supply, a feature that I really like is current limiting. That way you reduce the risk of frying your project or your PS if you have a short, oscillation or other cause of excessive draw.

[mypasswordis]

Yeah, current limiting would be nice as well. These benchtop supplies get really expensive really fast... and then I have to buy an oscope.

[grenert]

If the family doesn't come through on Christmas Day:

Hewlett Packard HP 6234A Dual DC Power Supply - eBay (item 360219838135 end time Dec-28-09 10:45:10 PST)

Small, bipolar supply. Current limited to 200mA. Should work great if you don't need more current.

[n_maher]

I would really appreciate some assistance finding a good, dual, tracking supply. This thread seemed like the right place to ask. Basically, what I need is a supply that I can use to troubleshoot and repair the beta22 channels that I have as well as some other projects that I'm working on so the minimum requirements are 0-30V, .5A (on both the + and - rails) and I certainly wouldn't complain about additional power or features. Budget is somewhat flexible, not looking to spend a ton, but I do like nice tools. I'd pick one on my own but I've been getting mixed reports about supplies that are stated to be "dual" that really just have two outputs and can't to + and - rails.

[luvdunhill]

I would really appreciate some assistance finding a good, dual, tracking supply

must it be dual tracking? I'm not sure those exist.

I have a pair of the ones mpwi linked to above, and plan on using them to troubleshoot a beta22 board or two really soon. Obviously, I won't be able to dial in the boards, as I'd need the final supply for that (due to the fact that you sorta get what voltage you get with the sigma22) but you can put them in current limiting mode and fire up a iffy board or two with them...

I'm trying to envision a "dual" supply that wouldn't work (i.e. these "mixed reports"), perhaps you have a link?

[Pars]

I know the B&K that I have is tracking (i.e., channel B tracks channel A) and they are isolated, so to do a +/- supply you patch the + of channel A to the - of channel B. Channel A is then the - supply and B the +. I don't think it will do 0.5A, don't think it has current limiting, and only does 25V on each (or is that 20?). Something close does exist though. I would look at the HP dual supplies if it were me.

This one that I linked previously appears to meet your needs:

http://cgi.ebay.com/Hewlett-Packard-HP-6228B-Dual-DC-Power-Supply-w-manual_W0QQitemZ360214245044QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item53de712eb4

Edited December 26, 2009 by Pars

[luvdunhill]

I know the B&K that I have is tracking

interesting. However, I'd take two very stable separate supplies, to an unstable tracking supply any day The HP looks to be a good choice in fact, assuming it is or can be brought up to the claimed specs.