Help me pick out a *NICE* Regulated Power Supply?

[masinyourface]

Howdy y'all! Been awhile, and I've been itching to get back in the pedal game!

So I've scrounged up about $300, and I'm wanting to buy a really nice regulated DC power supply for the bench. I'm looking for at least 30V at 3A. More power is obviously a plus, but my main concern is a rock-solid DC rail voltage. Having two channels that I could use independently or combine in series or parallel is a major plus.

Tektronix supplies look amazing, but I don't think I'd be able to afford one unless I found a good used deal.

In your opinion, what's the best bench power supply money can buy?

[PRR]

30V 3A is one heck of a pedal. Do you really need that much?

[blackieNYC]

I like MCM Electronics' prices for that kind of thing.  Looks like they start at $370.

[amptramp]

30 volts is an odd size although there are a lot of 24 volt and 28 volt supplies that may be adjustable up to 30 volts.  But you may find a ±15 VDC supply that works although they tend to be most popular in a 1 amp size.  Veeco - Lambda power supplies were the ones I used to order when I was working as a test equipment engineer but there are lots of others out there.  They also did some variable supplies.  You may be better off with a pair of 15 volt 3 amp supplies.

[chuckd666]

My friend has a Topward TPS4000. Apparently it can do 30V/3A. Cheap too.

[antonis]

what's the best bench power supply money can buy?

Current is great money eater..!! 

If you really need 3A, your transformer should be rated for more than 4A which results in 100VA (at least)..
(Bridge rectifier rated up to 5A, at least..)
For a decent voltage regulation (low ripple) you'll need a capacitor of about 22000μF..
Both the above yell for some kind of "soft start" circuit (due to inrush current)..
Your power transistor(s) should be rated up to 100W (at least) with a respective SOA (or use power MosFets) and BIG heat sinks, maybe with fan cooling fins..
(with respective temperature rise monitoring circuit..)
You'll definitely need some kind of fold-back current limiting, especially for output short-circuit protection..
You'll also need some kind of immediate output voltage "collapse" when switching power OFF..
...........................(list intentionally left incomplete).............................


So, do you REALLY need 3A..??

[armillary]

Lately I've been building a mic preamp, one of the projects from the RCA Solid-State Hobby Circuits Manual (HM-91) from the late '70s. It requires a 20V power supply. Based on overall value, I bought one of these:

http://www.ebay.com/itm/Elenco-Precision-XP-650-Deluxe-Regulated-Power-Supply-/172640924518

The listing title is for an XP-650 model, but the picture is of an XP-760 model. That's worrisome, so I strongly advise to ask the seller what model you are getting before you buy. You definitely want the XP-760 model in the picture, not an XP-650, which has fewer features.   

The XP-760 model is a discontinued USA-made unit with a fixed 5V@5A and two variable 1-20V@1A supplies. It has current limiting and short circuit protection. They used to cost about $300 new. It is by no means the best power supply money can buy, but to get one for $35 plus reasonable shipping seems like a good deal. And I'm cheap. 

The XP-760 manual is online here:
http://homepages.dordt.edu/ddeboer/DDB/EE_LAB/Elenco/xp-660.pdf

Sadly, it's only 1A.

The manual seems to suggest that you can jumper the ground terminal of one supply to the positive terminal of the other to obtain an output of 0-40V @ 1 ampere. I haven't tried that with mine. 

I'm not the seller of these, I just bought one a few weeks ago. I believe it was from the same seller, but using a different seller id. The XP-760 I got was listed as new, and was $65 with shipping included.     

[masinyourface]

Thanks for all the helpful responses y'all! I should probably note that this won't be solely for pedal building haha!

[highwater]

As a lurker/newbie, I hate to be the one to ask...

...but what are you planning to build?

[antonis]

I should probably note that this won't be solely for pedal building haha!

Then you MUST also have  - fixed at least - bipolar output haha.!!

[masinyourface]

Update: I decided on a Topward 6000 series power supply. They go used for about 300

[armillary]

For those still looking, these are still going for $35 plus $13 shipping. The listing has been corrected. I have one, and I like it a lot.     
http://www.ebay.com/itm/Elenco-Precision-XP-760-Deluxe-Regulated-Power-Supply-/172693288804?