Power Supply for vintage gear?

Hi Everyone!
looking for a replacement power supply for some vintage effects units - Yamaha Rev 7 / 5 and SPX (90 etc).
The original supplies can be recapped, but some units I have the supplies are actually missing!
The supply needs:

+/- 18V DC AND +5V DC output, with about 2A on the 5V DC output.

Have searched the internet, but can’t seem to find anything that matches this spec…
The original board is branded Yamaha LC 92750 circa 1980’s.Yamaha LC 92750
If anyone familiar with this type of supply or know maybe how to alter something available to fit the purpose I’d be very grateful.

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@smithster2010 You mentioned 10W for the +5Vdc supply. You didn’t mention the input, but I’m assuming AC mains input (100-240V?). What are the power requirements for the +/-18V supplies? Do the +5V supply and +/-18V need to be galvanically isolated from each other, or can they share a ground? This can be done in a single multi output power supply, another way may be to use a +/-18V supply and regulate the +5V from the +18v supply. Are there any “special” requirements (ie no switching power supply due to HF ripple, etc)?

Here is an example of one that does +5V +15V -15V at 40W that is low cost $30ea and in stock


Thanks for the reply. Not sure about your questions regarding ripple, isolation etc. as I’m not very PSU savvy. The link you gave is for +5 / +15/-15 - would that still work given the unit needs +/- 18V?
SPX90 schematic

I can rewire a PSU to match the inputs on the mainboard, but +5/-18/+18 seem to be very hard to find!
Thanks again.

Hi…my main PS are an Agilent E3610A and a 1965 era HP/Harrison 6113A. I picked up the agilent for $75 and its an outstanding unit. For $125, you should be able to get one that is virtually brand new-don’t settle for less. There are slightly different model numbers for different ranges-the 3610 is 0-15v, 3A. The other, lesser known models often go for less.
The 6113A is my favorite. These are hit or miss on ebay, but disgustingly simple to work on if you get a dud. I got mine for $35 and had to replace a cap, add a cal resistor and clean the thumbwheels. The abs difference between min and max at a setting of 2.5V over the last 48 hours is 0.00043V.

printed circuit board