Hell Matt,
That would be pretty wild. Can't do that. But I have seen it a long time ago. There was a large tube amp and they must have needed a small bias voltage at the grid. So, they just placed a battery there. Unless the amp was over-driven it didn't draw any current from the battery at all. However, when I opened this amp for repair the cause of all the grief was that this battery had leaked all over the place. I even had to re-paint the bottom panel.
This old battery looked cool, with a pouncing lion on there. I wanted to keep it but it was just too far gone.
Regards, Joerg
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