diytube.com

Nice work, Don!

http://www.diytube.com/forumpix/chassisnbox.jpg
http://www.diytube.com/forumpix/finalproduct.jpg
http://www.diytube.com/forumpix/underside.jpg

Shannon

Thanks, Shannon
Now for a question: The preamp buzzes, If I disconnect the grid on the second triode the buzzing stops. Any ideas? For reference:

http://www.diytube.com/forumpix/sch2.jpg

All the grounds in this circuit are tied to the input jack, this reduced the buzzing by about 80% but grounding the second grid stopped it totally.

Don

BTW some changes since this schematic

dhuebert wrote:Thanks, Shannon
Now for a question: The preamp buzzes, If I disconnect the grid on the second triode the buzzing stops. Any ideas? For reference:

http://www.diytube.com/forumpix/sch2.jpg
...
BTW some changes since this schematic

Hi Don,

Looking good! Could you email me the updated schematic? Some voltages with tube complement written on there would be great, too.

Shannon

New schematics in 2 weeks or so (on holidays)

Don

http://www.diytube.com/forumpix/power_amp.jpg
http://www.diytube.com/forumpix/power_supply.jpg
http://www.diytube.com/forumpix/preamp2.jpg

When I removed the paralleled input tube the buzzing stopped. My guess is that if the tubes are not exactly matched, something like a ground loop will occur, trying to force a node to two different voltages.

Don