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Hoffman Amps Forum image Author Topic: Trem-o-nator schematic & layout question?  (Read 1913 times)

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Offline tubenit

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Trem-o-nator schematic & layout question?
« on: August 14, 2020, 09:13:29 am »
I am often wrong and could be on this also?

It appears there is a discrepancy in some of the schematics and layouts showing the vactrol wiring for the trem-o-nator?

Can someone help me get this straightened out in my thinking, please? 

My trem-o-nator works fine in my amp, I am just trying to get my documentation to be consistent.

Thanks, Tubenit

Offline sluckey

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Re: Trem-o-nator schematic & layout question?
« Reply #1 on: August 14, 2020, 09:48:47 am »
That part of the Vactrol is just a resistor. And like a resistor, it makes no difference which way it it connected. I'm guessing this is related to the thread on TAG?
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline tubenit

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Re: Trem-o-nator schematic & layout question?
« Reply #2 on: August 14, 2020, 10:42:44 am »
I wondered if that was the case.  Yes, the TAG thread prompted my reviewing of what I had in documentation.

THANKS!  Tubenit

Offline yorgle

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Re: Trem-o-nator schematic & layout question?
« Reply #3 on: August 14, 2020, 02:22:10 pm »
Somewhat related to this- even though it's just grounding the signal, should wires in that path be shielded?  I ask because in my latest build, I'm getting a slight buzz that varies with the trem speed and disappears altogether when the resistor side of the vactrol is disconnected from the volume pot.

Offline PRR

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Re: Trem-o-nator schematic & layout question?
« Reply #4 on: August 14, 2020, 09:34:01 pm »
> should wires in that path be shielded?

Or minimized.

It's gotta be a high-impedance point. So the more wire you hang off it, the more crap it will pick up. The LDR can perhaps be right AT the audio path; the LED wires can be long.

 


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