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Buy a cheap Power Supply or DIY/Mod my old PC PSU ?
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Jwillis:

--- Quote from: james_s on June 03, 2018, 05:20:22 pm ---Well sure, if you have the time and the budget then go for the build, power supplies were some of the first projects I built and I still build them from time to time when I need something in particular. It is nice to have one commercially made power supply with all the bells & whistles though.

--- End quote ---

I can understand your frustration.I've been in your shoes....No really I swiped them last night.

First off .What do you want and what is your budget.You won't get fancy and cheap in the same box.
You can try a cheap Chinese special switch mode power supply, but that's a roll of the dice.You might get a good one you might not.

So  I suggest Linear all the way.This at least guarantees a degree of isolation from mains high voltage because of the transformer.
Much quieter and safer for you and your projects and much easier to fix if something does go wrong.

Any of the HY3005 type linear power supplies use the same tried and true design.It doesn't matter which brand.
For a single unit they run around  GBP 150+SH where as a double runs around   GBP 300+SH .But with a little searching you might find one cheaper either new or used.

Good luck and cheers.

Nice shoes by the way.
Discotech:

--- Quote from: james_s on June 03, 2018, 05:20:22 pm ---Well sure, if you have the time and the budget then go for the build, power supplies were some of the first projects I built and I still build them from time to time when I need something in particular. It is nice to have one commercially made power supply with all the bells & whistles though.

--- End quote ---

Time is something I am fortunate enough to have plenty to spare, so I think I'll go the route of modifying my ex PC PSU, then if it doesn't suit my needs either attempt build another from scratch or just buy something decent

I'm trying to do things cheap"ish" but even cheaply costs are starting to add up  :scared:
james_s:
More than once I've been guilty of trying to take the cheap route and spending more than I would have to just do it right the first time. It certainly is possible to save money if you can cobble something together out of bits you already have. In fact one of my most used bench PSUs is one I built out of a 32V power brick from a thrift store, one of those Chinese switching regulator modules and a digital V/A meter stuck in a project box I salvaged from something at work. I use it often because it's compact and light weight, I initially used a 3A module but it blew up under close to full load so I replaced it with a 5A module that I derated to 3A. The constant current mode has some ugly oscillations but it does work ok.
rstofer:
Mostly I just use my bench PS for +5v for logic and +-15V for op amps.  Having current limiting is very nice when bringing up a new project.  If I were to say 'get a power supply', it would be for current limiting a new design so that it doesn't melt.

I also have the Sparkfun kit for the PC PSU.  Funny thing, I have never used this supply.  Among other things, it has too much short circuit current.  Fuses help but this PS can melt a project to the ground without getting warm.

https://www.sparkfun.com/products/12867

While you are at Sparkfun, search for 'power supply'.  There are a lot of alternatives.

Search around EEVblog, this topic comes up every week or so.  Everybody wants to build a power supply with all the bells and whistles for essentially no money.  A real power supply is a pretty complex piece of equipment.  If I wanted to build something cheap, I would look at a project with a 7805, 7815 and 7915.  These are the important voltages and 3.3V can be easily derived from 5V.  Sparkfun has stuff for this.  There are plenty of these 3 output power supplies on eBay.

I have the Rigol DP832 and it's pretty nice.
Mr. Scram:
Getting one of those Tenma supplies certainly isn't a bad idea. Having a proper and reliable voltage and current setting is very helpful.
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