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Hoffman Amps Forum image Author Topic: First power on question.  (Read 1801 times)

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Offline chocopower

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First power on question.
« on: February 19, 2018, 04:08:06 pm »
New rebuild amp.
I have no variac, but i use a step down transformer (220v to 120v) so in the first power on, amp get lower voltage. I'm from Spain. 220vac here.
I use too, a current limiter bulb.
My question is:


220vac---step down transformer----bulb---amp


Or


220vac---bulb---step down transformer---amp




I only have 220vac bulbs, so i dont know how they could work after the stepdown transformer.


Thanks in advance.



David

Offline sluckey

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Re: First power on question.
« Reply #1 on: February 19, 2018, 04:21:30 pm »
I suggest 220v to current limiter bulb to amp. Forget about the stepdown transformer.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline chocopower

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Re: First power on question.
« Reply #2 on: February 19, 2018, 04:39:22 pm »
Thats the way i use to do... but this time im a bit worried about P.T. primary wiring. Is a old amp and wires are  bit confusing im primary side.
I'm 99.99% sure about my work, but in the catastrofic situattion i picked a 120v primary widding, i want to use the step down transformer.....


I realize that i'm being a bit paranoic, but ....
David

Offline kagliostro

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Re: First power on question.
« Reply #3 on: February 19, 2018, 05:51:40 pm »
..... 220V line > Lamp Limiter > 220V/110V Step Down Transformer > Amp  (may be ???)


Franco
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