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Hoffman Amps Forum image Author Topic: Cheap nos tubes  (Read 2891 times)

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Offline clayman

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Cheap nos tubes
« on: June 28, 2021, 01:02:11 pm »
6by7 pentode. Can this be used as a preamp tube?

Offline PRR

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Re: Cheap nos tubes
« Reply #1 on: June 28, 2021, 02:36:09 pm »
Almost any tube can be "a preamp". But is it still "cheap" if you have to experiment to find a happy-point?

Offline kagliostro

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Re: Cheap nos tubes
« Reply #2 on: June 28, 2021, 04:28:29 pm »
From the pages of Heinz, a friend of the forum



http://jschem.bplaced.net/t7/

--

As you can see here EF85 in equivalent to the 6BY7

http://tdsl.duncanamps.com/show.php?des=6BY7

Franco
« Last Edit: June 28, 2021, 04:33:20 pm by kagliostro »
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Offline clayman

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Re: Cheap nos tubes
« Reply #3 on: July 04, 2021, 02:48:01 pm »
Has anyone used 6aq5 in place of 6v6? I know I would have to use 7pin socket, rewire.

Offline sluckey

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Re: Cheap nos tubes
« Reply #4 on: July 04, 2021, 02:58:34 pm »
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline clayman

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Re: Cheap nos tubes
« Reply #5 on: July 04, 2021, 03:11:17 pm »
Steve, your link doesn't work. Fixed, thanks
« Last Edit: July 04, 2021, 03:15:46 pm by clayman »

Offline kagliostro

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Re: Cheap nos tubes
« Reply #6 on: July 06, 2021, 07:01:09 am »
To me the link works correctly

Franco
The world is a nice place if there is health and there are friends

Offline Latole

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Re: Cheap nos tubes
« Reply #7 on: July 06, 2021, 07:40:11 am »
To me the link works correctly

Franco


To me too.

 


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