0-30V 2mA - 3A Adjustable DC Regulated Power Supply DIY Kit Short Circuit Current Limiting Protection

If you are in need of a low power, inexpensive adjustable (volts & amps) power supply, this may be the answer. The kit is very well made. The instructions are a bit vague, but online help is available. Mine sits atop nylon standoffs but I would prefer an acrylic case. Maximum voltage is 24 VAC only and they are not kidding. I fried my first one when I powered it with a 24 VAC control transformer, whose actual output voltage was actually 27.12 VAC. By using an adjustable transformer and keeping the supply voltage below 22 VAC (just to be safe) the unit works very well. Also be apprised that the D1047 transistor definitely needs a fan cooled heat sink. There is a plug for the fan, but not all kits come with the fan.

Burnt up the D1047 power transistor...twice. Replaced with a NTE36, and it worked fine.Ran the outputs through a relay, and pull it in with a bistable switch made with a 555 timer with a lighted push button. Fun project. The silk screen works fine to build it, but a schematic would be helpful for troubleshooting.

I built two of these. They are certainly inexpensive. I have decades of electronic experience so assembly was simple. Neither would work at all until I replaced all three TL081CP OP Amps with American made ones. Then both supplies produced a variable DC voltage but the amperage control circuits did not control properly. They both performed exactly alike. I even tried two different brands of transformers. After two days of trouble shooting I have decided that they are not worth fooling with. Into the garbage and get on with life.

three stars for seemingly good product with no instructions. contacted seller and received directions to a non existant link

With the help of Sophie , thank you Sophie , I got a schematic , parts list and assembly instructions .Awesome value for a lab power supply . Finished soldering and it powered up first time . Works great .

dont work no output power after 2 kits

Only problem with this unit is the adjustments are too close together otherwise it works great under load and it holds voltage and current accurately.

Nice kit mine was perfect nothing missing and they even included the big heat sink and fan that comes with the higher priced version of this. I don't know if they did that by mistake or they all come with it now. The only reason it's not 5 stars is the lack of information on finding a power source. You need a 24V AC transformer. To use the full 3A you need at least a 24VAC 75VA transformer like this: https://www.amazon.com/Diversitech-T6753-Trans-75Va-120Pri-Sec/dp/B00O948AQO/ref=sr_1_9?rps=1&ie=UTF8&qid=1497520747&sr=8-9&keywords=75va&refinements=p_85%3A2470955011. I got a 40VA one made by Packard for $15 which works great as long as I keep it under 2 amps.