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Hoffman Amps Forum image Author Topic: 120 Volts on Front Panel?  (Read 2523 times)

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Offline Fresh_Start

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120 Volts on Front Panel?
« on: June 21, 2010, 12:27:44 pm »
I'm thinking about using a Marshall lighted, rocker power switch on a build for myself.  Seems like it would be nice & clean from a layout perspective, and I like the idea of a 2-pole power switch so both hot & neutral get switched.

Having 120 volts on the front panel makes me a bit nervous, even though this amp is just for my use.

What do you all think about the potential danger? 

Is it any worse than 120 volts and a power switch on the back panel where you may be fumbling around for the switch by feel?

On a related topic, has anyone ever tried a voltage divider off of a power tube plate to get a plate voltage test point?  IOW Vp => 1 meg resistor => test point => 111,111 ohm resistor => ground.  10% of plate voltage & very little current on the test point if my calculations are right.  Might not be worth the effort of matching up resistors...

Cheers,

Chip
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Offline sluckey

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Re: 120 Volts on Front Panel?
« Reply #1 on: June 21, 2010, 12:45:59 pm »
No problem with 120VAC on the front panel. There's a lot more stuff with the power switch on the front than on the back. I never liked Fender's rear panel switches, but it did make a clean looking front.

I wouldn't bother with a voltage divider test point unless the voltage was sooo high as to be dangerous to the test equipment.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

 


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