The PHILCO Phorum
Sub for 6F6G tube - Printable Version

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Sub for 6F6G tube - Tucker - 01-07-2018

Can I safely substitute a 6V6G (or 6V6GT) tube for a 6F6G tube in a 37-630T radio ?  I've read that the current draw might be different so I'm not sure this would work?

RE: Sub for 6F6G tube - morzh - 01-07-2018

In pushpull output it is not recommended to sb 6f6 for 6v6.
OK for SE outputs.

RE: Sub for 6F6G tube - Radioroslyn - 01-07-2018

The '630  has a single output tube so your good.

RE: Sub for 6F6G tube - Tucker - 01-07-2018

Ok, thanks!

RE: Sub for 6F6G tube - Arran - 01-08-2018

The 6V6/6V6/6V6GT is actually a good, if not better substitute for a 6F6 or 6F6G, but it depends on how the original tube was biased. If the original tube, or tubes in the case of a push pull output stage, are cathode biased (or self biased) then you can use either tube type, but if the tubes use fixed bias then some circuit modification will have to be done as each tube requires a different bias voltage. I don't know which sort of biasing was used in the 37-630, one way to tell is if there is a resistor connected between the cathode of the 6F6G tube and B-, if it has then it is cathode biased, if not then it's fixed biased.