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Hoffman Amps Forum image Author Topic: AC30/6 Parts Question  (Read 1845 times)

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Offline mjcyates

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AC30/6 Parts Question
« on: May 08, 2021, 07:33:14 am »
I am building an AC30/6 and am trying to find the right part for the 2 way rotary switch for Vib/Trem and the 3 way rotary switch for Speed. Can anyone suggest a good choice for these switches and where I can get them. Doug sells a 3 way impedance switch in his store which would probably work but may be a little overkill for this application. Any help would be greatly appreciated.

Offline sluckey

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Re: AC30/6 Parts Question
« Reply #1 on: May 08, 2021, 08:15:38 am »
Here's a 3 position rotary that is small and will work fine.

     https://www.tubesandmore.com/products/switch-rotary-3-poles-3-position

     https://www.mouser.com/Alpha-Taiwan/Electromechanical/Switches/Rotary-Switches/_/N-5g2i?P=1z0zlgnZ1yvsm2e

And here's a 2 position from Mouser.

     https://www.mouser.com/Alpha-Taiwan/Electromechanical/Switches/Rotary-Switches/_/N-5g2i?P=1z0zlgnZ1yvsm2a

I just used a 3M-RA pot in series with a 220K for a variable speed rather than only 3 fixed speed selections on my AC-15. I also just used a toggle switch for the vib/trem and Brilliance switches.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline pdf64

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Re: AC30/6 Parts Question
« Reply #2 on: May 08, 2021, 08:53:12 am »
I suggest to use 1M or 10k CTS pull-push switched pots for both.
Swap the tracks with those from CTS 3M3RA and 500k lin pots.
Use one for modulation oscillator on/off (in parallel with or replacing the footswitch) and oscillation freq.
Use the other for vib/trem selection and effect depth (replacing the depth preset trimmer VR5).
Hey presto, increased range of control and convenience, no alteration to the front panel or its aesthetics.
« Last Edit: May 08, 2021, 08:59:31 am by pdf64 »
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Offline mjcyates

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Re: AC30/6 Parts Question
« Reply #3 on: May 08, 2021, 09:01:10 am »
Thank you both for the suggestions! Much appreciated.

 


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