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Hoffman Amps Forum image Author Topic: Ampeg SVT-CL, 12vac fan off IEC input?  (Read 2352 times)

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Offline bigdaddydiesel

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Ampeg SVT-CL, 12vac fan off IEC input?
« on: December 04, 2020, 08:47:17 pm »
Hi, I have an SVT-CL. It's working well after some new tubes and repairing some bad solder joints incl. one that was causing a cathode resistor to lose connection and put the amp into fault protection mode. I've noticed that a lot of heat collects inside the head case and the stock fan on the front baffle isn't quite cutting it. I was kicking around the idea of mounting a second AC-powered PC fan on the rear grate and sneaking its 2-prong umbilical underneath the grate. However, I noticed there's a bit of space in the route for the power transformer leads on the top side of the chassis and got to thinking -- Would I be causing any issues by connecting a 12vac fan in series off the amp's IEC input?

I would of course also wire up a molex connector so the grate and fan can be disconnected when future service is required.

Thanks!

Offline sluckey

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Re: Ampeg SVT-CL, 12vac fan off IEC input?
« Reply #1 on: December 04, 2020, 09:00:11 pm »
Quote
Would I be causing any issues by connecting a 12vac fan in series off the amp's IEC input?
yes
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline bigdaddydiesel

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Re: Ampeg SVT-CL, 12vac fan off IEC input?
« Reply #2 on: December 04, 2020, 09:35:48 pm »
Quote
Would I be causing any issues by connecting a 12vac fan in series off the amp's IEC input?
yes

Er, I meant parallel.  :think1: Hot to hot, neutral to neutral.

Offline sluckey

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Re: Ampeg SVT-CL, 12vac fan off IEC input?
« Reply #3 on: December 04, 2020, 09:55:52 pm »
Not gonna work.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline bigdaddydiesel

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Re: Ampeg SVT-CL, 12vac fan off IEC input?
« Reply #4 on: December 04, 2020, 10:09:17 pm »

Offline AmberB

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Re: Ampeg SVT-CL, 12vac fan off IEC input?
« Reply #5 on: December 05, 2020, 12:05:14 am »
You can use a 120 volt fan that way by tapping off the AC input.  You would fry a 12 volt fan very quickly...

 


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