Peavey Encore 65 , adding a 12 VDC cooling fan

[Sigala]

Has anyone had experience on adding a 12 VDC cooling fan to the Peavey, to help with the heat buildup in the chassis!
I am thinking of adding on in the chassis, Peavy had stated that the problem with this older amps was the circuit board would warp due to the heat build up?
I was looking at the schematic to see if, I could tap off the +27 V supply, but not sure of the best method circuit wise. Voltage regulator or ?? I f any one has done this mod, I would appreciate any help on a circuit to accomplish this.
I have included a schematic

Dennis

[olddawg]

Has anyone had experience on adding a 12 VDC cooling fan to the Peavey, to help with the heat buildup in the chassis!
I am thinking of adding on in the chassis, Peavy had stated that the problem with this older amps was the circuit board would warp due to the heat build up?
I was looking at the schematic to see if, I could tap off the +27 V supply, but not sure of the best method circuit wise. Voltage regulator or ?? I f any one has done this mod, I would appreciate any help on a circuit to accomplish this.
I have included a schematic

Dennis

I would use a 120 volt fan and wire it after the power switch. If you already have a 12v fan just get a tiny 12v transformer to power it. A $3 wallwort type works nicely.

[Sigala]

Thanks for getting back to me on this!
I wanted to use 110 AC, but could not find any small enough at Radio Shack!
But that is a great idea, using transformer! So just a plug in adapter transformer?
Thanks for your suggestion
Dennis

[nashvillebill]

Well, you could get TWO of the smallest 12 VDC fans you can find and wire them in series, straight off the 27VDC supply... Or just get a 24VDC like this one http://www.allelectronics.com/make-a...ING-FAN/1.html and wire it off the 27VDC supply, assuming you have 60 mA to spare on that circuit.

[Sigala]

Hi nashvillebill!
Thanks for the input, I went with olddawg suggestion, of using a Wall 12vdc transformer I wired it direct to the power switch, I mounted the fan inside the chassis, exhausting out!
hopefully this will help with the heat buildup.
Thanks to everyone for all your suggestion and invaluable help

Sincerely
Dennis Sigala