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Hoffman Amps Forum image Author Topic: Hoffman/Randall amps  (Read 4618 times)

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Offline EL34

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Hoffman/Randall amps
« on: October 03, 2008, 09:21:36 am »
Revision D of a Hoffman/Randall

This is a 50watt version.
Just add two more power tubes and the parts that go with a power tube.
Like 1K screen grid resistor, 5.6k input grid resistor and 1 ohm cathode resistor.
Change the feedback resistor to a 100k for a 100 watt version.
« Last Edit: October 06, 2008, 06:42:33 am by EL34 »

Offline EL34

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Re: Hoffman/Randall amps
« Reply #1 on: October 06, 2008, 06:36:35 am »
This post has revision D .sch file

I split this topic off the hoffman randall topic in the big board
http://www.el34world.com/Forum/index.php?topic=4098.new#new

I still haven't gone over the schematic with a fine tooth comb to check for errors

My original layout diagrams for these amps are on the library page
They are split into pre amp and power amp


« Last Edit: October 06, 2008, 06:39:30 am by EL34 »

 


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