Intellix 8001 mixer power supply

[Jim Coash]

Greetings:  I was given two Intellix 8001 mixers.  One has a power supply, the other is missing.  Both work with the supply I have which says it has an A/C output of 18vac.  The connector to the mixer is a round four pin one and I measure about 10V A/C on each of two legs to the center tap of the transformer.  The #4 pin is NC.  I have a bunch of old wall wort power supplies but nothing that is quite the same.  Most are DC.  I have found exact replacements on-line but they don't come cheap.  If anyone has something that will work, I would be interested.  Jim

[Ritchie200]

Jim,


Any chance of finding a tranny that will give you those voltages?  You can always build something?


Jim

[Jim Coash]

I have a supply that is for an older computer.  It seems large enough but is DC.  Perhaps I can just bypass the rectifier and feed both sides of the chassis with the same output.  Jim

[jojokeo]

Jim, You need to also know what kind of mA (or possibly VA) rating along with the voltages to assure enough power can be supplied similar to a DC wall wart. 18vac seems "suspicious" in that I suspect that the mixer itself simply converts the AC power into a bipolar power supply internally feeding the op-amps inside. This would commonly provide +/-9vdc to the circuitry. I know nothing of what you have, what it looks to be made of and when, etc...so I can only make an educated guess that this is the case. For high end audio it helps with headroom and other related things not necessary to go into. I'm attaching a schematic of what the supply would likely be composed of inside the mixer and the transformer you currently have is likely simply serving similar to the one on the schematic. Also I found something about what you possibly may have??? (is it in fact one L and not two in Intelix?)

[Jim Coash]

Thank you.  I think I have all the parts as long as I can find a suitable transformer.  I have about a dozen taken form various audio components.  Intelix warns me to use ONLY their supply but they want a lot for them.  I plan to rack this unit with a Carver amp and some signal processing components for PA use so I can just hard wire it and mount it in the back of the rack.  Jim

[sluckey]

Salvation Army and Goodwill usually have a big box full of wall warts. Worth checking out. May Just find what you need.

[jojokeo]

Jim, to be clear all you need is a transformer, the other circuitry for the supply is built-in already.
I find that old telephone answering machines and such are many times powered by AC transformers. Besides what Sluckey suggests a simple cneter tapped Radio Shack tranny could also work. You just have to find a way to make a connector or modify this area is all. It would be a good idea to disassemble and look inside of the power-in area and visually verify the caps and 7809 7909 transistors also if possible? But then again, you have the other unit and power supply so you know it'll work if you just supply the power in the same way. Good luck and let us know how it turns out?