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September 07, 2025, 06:52:17 am
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Hoffman Amps Forum image Author Topic: Pro Junior Layout  (Read 424 times)

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Offline CrasseDeMeule

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Pro Junior Layout
« on: September 03, 2025, 01:29:05 am »
Hi all!!
Based on the Hoffman schematic, here is the DIYLC file for those who would like to use...
Many people use PDF, but many use now DIYLC now...

I also integrated a impedance switch mod.

Offline EL34

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Re: Pro Junior Layout
« Reply #1 on: September 03, 2025, 04:33:52 am »
Nice work
If you want, I will upload these to the .diy library?

Offline CrasseDeMeule

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Re: Pro Junior Layout
« Reply #2 on: September 03, 2025, 07:21:44 am »
No problem!
But as a newbie, a quick check from an expert would be safer!
Around the PT, B+, and the choke, I'm not sure 100%

Also as I didn't receive the PT yet, I mybe haven't put the right colours

Offline CrasseDeMeule

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Re: Pro Junior Layout
« Reply #3 on: September 04, 2025, 02:09:36 am »
Little corrections on the schematic,

Bridge rectifier added
A mistake corrected on the green wire from the cold point of the input jack
Rewiring of the 6.3V, more convenient like this


Offline EL34

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Re: Pro Junior Layout
« Reply #4 on: September 04, 2025, 06:04:55 am »
Just check against my layout
Use a sharpie to follow each trace on paper

https://el34world.com/Hoffman/files/Hoffman_Pro_Jr.pdf

Offline CrasseDeMeule

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Re: Pro Junior Layout
« Reply #5 on: September 04, 2025, 06:31:36 am »
That's what I did, with this schem, and the more modern one that you uploaded as well.
Everything looks good to me now.

 


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