Using only half of dual triode. Ground unused half?

0dbfs

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Hi,

I am using half of a dual triode in a tube mic circuit.

I was wondering if it is best to ground the tube connections for the half that is not used. ie; A2, G2, K2...

Thanks in advance!

Best,
j
 

0dbfs

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Roddy,

Thanks!

This tube is a 6BS8:
http://tubedata.itchurch.org/sheets/093/6/6BS8.pdf
Used in the Bulldog 49 circuit.
That tube in particular shows no connection for pin9 as being the heater center tap. I'll measure to confirm that just for fun though.

I was posing the question for general information although I did not ground those connections when I initially assembled mine. I'll have to sort that out soonest.

If the single heater connection heats both cathodes, what affect might leaving the second unused half of the triode ungrounded have?

Best,
jonathan
 

PRR

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> what affect might leaving the second unused half of the triode ungrounded have?

Probably very little.

Ya know, 6J6 is the same triode except common-cathode. Which does not matter to you. And there were bazillions of 6J6 made; I never knew there was a 6BS8.
 

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PRR,

PRR said:
> what affect might leaving the second unused half of the triode ungrounded have?

Probably very little.

Thanks for the input! Seems like grounding the unused pins might make for a "best practice" in any case.

PRR said:
Ya know, 6J6 is the same triode except common-cathode. Which does not matter to you. And there were bazillions of 6J6 made; I never knew there was a 6BS8.

The 6J6 looks interesting in a 7 pin base opposed to the 9 pin 6BS8. Common cathode is interesting as well. Datasheet explains that it is ideal for parallel or push/pull with parallel plates operation.
I might try some different tubes in my situation (other than the 6BS8) as well just to see the differences.

Best,
jonathan
 

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