[ARC5] Bias Battery

[Hubert Miller]

I always thought the smartest way to get -bias was the resistor in the B- lead to ground. If you just need say, -4.5,
this is not a serious loss to the B+.
This is fine for a civilian type radio with battery snaps but when you have an ex-military radio like the BC-474, some
ham is going to see 2 two wires for B supply and say, well why not just connect the B- to chassis? And a little later,
he wonders why the audio output transformer went.
"Contact bias" via a high R grid resistor is fine but only gives you, I think, up to about -1.5 volt.
I saw one trick circuit in a 1950s Radio News that used the electrons on the grid, via "contact bias", to power a
small oscillator with the same tube, very low power oscillator. And no – the filament was not connected to the oscillator
circuit, so it wasn't getting its B+ that way.
-Hue

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