[S Clark]

These variable 30V 3A power supplies are cheap, but are they quiet and dependable?  Anyone have one?

http://www.amazon.com/Tekpower-HY1803D-Variable-Power-Supply/dp/B000CSQK5E/ref=sr_1_5?ie=UTF8&qid=1390333346&sr=8-5&keywords=mastech+power+supply

[dlipter]

I have a similar one. Had it for many years with no problems. I mounted a fan on the heatsink for sustained use. I would first obtain a schematic diagram for future servicing before buying.

Dennis

P.S. It is quiet except for occasional clicking relays.

[Quiet Earth]

I have that very same power supply. I bought it several years ago to run a squeezebox duet receiver. The only negative thing I would say about using it for that kind of situation is the fact that you can accidentally change the voltage setting because it is adjustable. Other than that it is a fine power supply within its limits. I still use mine to do other things on the bench, little projects and such. I think it's a good value.

There is a single click when you adjust the voltage setting (or current setting?) somewhere above the mid-way. Other than that is very quiet. It's also heavy for its size. Hope that helps.