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Hoffman Amps Forum image Author Topic: AB763 One Channel - Add a filter cap  (Read 1588 times)

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Offline 6v6Pin1

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AB763 One Channel - Add a filter cap
« on: July 29, 2020, 11:27:05 am »
I have an unused 16uf/450v cap available on this build. I was thinking about adding a 1k resistor and the filter cap to create an E power node.
Which triode(s) would benefit most from being moved to the E power node?
https://el34world.com/Hoffman/files/Hoffman_AB763_1.pdf

Offline sluckey

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Re: AB763 One Channel - Add a filter cap
« Reply #1 on: July 29, 2020, 11:31:37 am »
I would power V1 from node E. Put resistor between node D and node E. You can use a larger resistor since the current is so small.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline 6v6Pin1

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Re: AB763 One Channel - Add a filter cap
« Reply #2 on: July 29, 2020, 12:32:42 pm »
Ok thanks! I'm going to try it out.
The V1 voltages are where I want them now. I don't want to drop too much. Is there a rule of thumb on how small that resistor can be?

Offline sluckey

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Re: AB763 One Channel - Add a filter cap
« Reply #3 on: July 29, 2020, 01:13:17 pm »
My thumb says use the resistor value that gives you the node voltage you want.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

 


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