I went to my favorite surplus place and found a couple of Heathkit power supplies for $5.00 each. The hoarder in me could not resist.
Are their TUBES inside
If you haven’t found it already:
If the 5V supply cooks, you might want to replace the UA309K with a modern 5V linear regulator. Most of the other parts are probably easy to find. The circuit board was definitely laid out by hand!
No tubes…
@mcdanlj Nice find! I have not really started to play with them yet but had some ideas. The variable 20 volts is a bit wimpy at half amp so I was going to see what I could do with that. It’s still amazing what you can do with some of the variable Buck converters and a computer power supply!
Use LM317 for both the fixed 5v and higher current adjustable. Or make them both adjustable.
An ebay or amazon search for DP50V5A will find the modern cheap front end in a few variants.
I went for the EEZ Bench Box 3 which cost more but man it’s full of features. I tried to price out comparable feature set in a non-open-source unit and nearly fell out of my chair.
@mcdanlj I have been eyeing EEZ Bench. It looks like a great power supply and of course has great reviews. I do have an old analog 24 volt 6 amp power supply that is as large as a shoebox. I want to make a variable supply out of it but the size and weight always keeps me from doing anything. My other idea is to use it on a larger CNC I would like to build someday. Maybe when I get to the point of Don and enjoy a retirement, I’ll be able to do all the projects on my list!
I retired at age 40, but am now running two separate businesses which is becoming a full time job. IU should be on a beach somewhere, but keep getting sucked into new business ventures.
The only difference between being retired or not;
Now I get to work on what I want to work on with whom I want to work on it.
Well said Don.