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Hoffman Amps Forum image Author Topic: ***corrected***Vox AC30/4 layout drawing..  (Read 4048 times)

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Offline Jalmeida

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***corrected***Vox AC30/4 layout drawing..
« on: June 17, 2023, 11:41:49 pm »
Hey all,

***Updated*****

I have been tinkering with my next build in between things and I have been lucky enough to have been gifted a Vox AC30/4 repro chassis setup from a super cool amp guy. So my next build will be an AC30/4 fawn head.

Anyways, I have been learning how to use DIYLC and as a learning opportunity i put together a layout diagram for the AC30/4. Thought i’d share for anyone interested. I’d recommend it get proofed against the schematics. 

***FYI this layout is based off the original layout. ****
« Last Edit: September 26, 2023, 12:55:22 pm by Jalmeida »

Offline Jalmeida

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Re: ***corrected***Vox AC30/4 layout drawing..
« Reply #1 on: June 25, 2023, 04:11:21 pm »
Original layout files replaced with updated. Attached schematic.

Updated Schematic correcting a few resistor labels.
« Last Edit: July 09, 2023, 09:30:51 pm by Jalmeida »

Offline jojokeo

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Re: ***corrected***Vox AC30/4 layout drawing..
« Reply #2 on: June 29, 2023, 11:33:15 am »
Congrats on the amp! Not a fan of using the chassis as a ground plane but otherwise it looks great. In case you're wondering what this means? Run the preamp and output tube grounds directly to their respective power filter caps' grounds eliminating the ground lugs to chassis, then run them all to the power transformer bolt lug location since there's not a HT center tap for the resevoir cap. Also, there's no center tap for the heater wiring. I'd run a couple 100r's to ground forming a virtual center tap here as well.
To steal ideas from one person is plagiarism. To steal from many is research.

Offline Jalmeida

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Re: ***corrected***Vox AC30/4 layout drawing..
« Reply #3 on: June 29, 2023, 12:58:11 pm »
Congrats on the amp! Not a fan of using the chassis as a ground plane but otherwise it looks great. In case you're wondering what this means? Run the preamp and output tube grounds directly to their respective power filter caps' grounds eliminating the ground lugs to chassis, then run them all to the power transformer bolt lug location since there's not a HT center tap for the resevoir cap. Also, there's no center tap for the heater wiring. I'd run a couple 100r's to ground forming a virtual center tap here as well.

Thanks for that. I made this to represent the original AC30/4 layout. They could have made many improvements to this layout with regards to ground practices. But this will get you original layout if one is doing an authentic build. 

Offline Jalmeida

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Re: ***corrected***Vox AC30/4 layout drawing..
« Reply #4 on: July 04, 2023, 02:43:54 pm »
 Updated to add schematic.

Offline Jalmeida

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Re: ***corrected***Vox AC30/4 layout drawing..
« Reply #5 on: July 09, 2023, 02:10:49 am »
Rev 4 Layout corrects input jacks.

Offline sluckey

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Re: ***corrected***Vox AC30/4 layout drawing..
« Reply #6 on: July 09, 2023, 09:37:05 am »
Rev 4 Layout corrects input jacks.
The HI/LO jacks are mislabeled. The jacks with the 1M are the HIGH jacks.

Also, the alternate speed pot is miswired. The blue wire should be on the right-hand lug.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Jalmeida

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Re: ***corrected***Vox AC30/4 layout drawing..
« Reply #7 on: July 09, 2023, 09:25:03 pm »
Rev 4 Layout corrects input jacks.
The HI/LO jacks are mislabeled. The jacks with the 1M are the HIGH jacks.

Also, the alternate speed pot is miswired. The blue wire should be on the right-hand lug.

I sure did! Thanks for that. Corrected on the layout an uploaded. I wouldn't have caught that until power on likely. Possibly not at all on the High/Low Jacks.

Offline Jalmeida

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Re: ***corrected***Vox AC30/4 layout drawing..
« Reply #8 on: July 09, 2023, 09:25:56 pm »
Rev 5 uploaded with Sluckey corrections.

Offline Jalmeida

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Re: ***corrected***Vox AC30/4 layout drawing..
« Reply #9 on: September 26, 2023, 01:06:59 pm »
Corrected layout page 1 to R6 and corrected schematics as well.

 


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