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.

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.

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 .

The board is well made and labeled. However, no instructions. I was able to figure out most of the parts but some are difficult to read small size. The problem is that it doesn't work. Output is just a few millivolts regardless of the settings of the pots. It does get unusually warm in the area of the three ICs. Power in is correct. Unfortunately, with no circuit diagram and no instructions, it's impossible to trouble shoot the problem. The circuit seems unnecessarily complicated. A linear regulator could consist of a voltage reference IC and a few power transistors. However, this circuit includes about 25 resistors and 15 diodes and three ICs plus capacitors, etc. and I have no idea what they are all doing.

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

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.

A really good bargain and it comes with the heat sink and fan!! Goes together really easy and had been stable in the few weeks that I have been using it. Purchasing the individual components

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.