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Hoffman Amps Forum image Author Topic: Ab763 filter cap grounding photos?  (Read 2312 times)

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Offline nickp

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Ab763 filter cap grounding photos?
« on: April 29, 2017, 08:00:54 am »
Im building a one channel ab763 and i like the approach of putting the big electrolytics in the chassis tucked below the pots.

Id love to see some pix of how people have grounded these.  Do you just connect to one of the rails on the board that goes to the PT bolt?

Thanks. 

Offline tubenit

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Re: Ab763 filter cap grounding photos?
« Reply #1 on: April 29, 2017, 08:20:27 am »
Excellent info on grounding right here even though it's not an actual photo

http://el34world.com/charts/grounds.htm

Offline nickp

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Re: Ab763 filter cap grounding photos?
« Reply #2 on: April 29, 2017, 09:57:50 am »
Interesting.  Thanks. 

Different than the Layout posted, though, which shows all the big caps grounded at the PT (see page 2 of 5):

http://el34world.com/Hoffman/files/Hoffman_AB763_1.pdf

Offline sluckey

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Re: Ab763 filter cap grounding photos?
« Reply #3 on: April 29, 2017, 10:09:39 am »
Here's Hoffman's AB763 project. It shows the caps mounted between the board and pots. Negative end connects to the pot buss on the back of the pots. The plate and screen node caps connect the negative end directly to a PT bolt at the same place the PT center tap connects.

     http://el34world.com/Hoffman/AB763Project.htm
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline nickp

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Re: Ab763 filter cap grounding photos?
« Reply #4 on: April 29, 2017, 10:30:56 am »
Well, I am a giant dum dum (not news to those who know me).  I was looking at those very pictures, and failed to notice the negarive end going to the ground bus. 

Thanks!

 


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