I am guessing about the 3 volts then connect to the ballast tube, as the filaments are 2 volts (This maybe the tall battery you are referring to)
Yes 2 D cells would work but you need something that has more reserve for the filaments. Maybe 2 (1- 1/2 volt) Lantern batteries.
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3 (45 volt batteries) in series = 135 Volts,
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I noted that on (page 6-48 of the next SEARS models down ( Models 1922-A,1932-A, 1982-A, 1992-A) the 45 volt packs there is a 22.5 volt terminal tap. On the tube positions and battery connections Funny it doesn't show them being connected in that circuit.
The green wire is a 22 volt battery for the (+) and using an external battery would use The - B connection as a return. (I am assuming this since the battery pack shows only one 22 volt connection , being that case the other end of the 22 volt is internally connected to the (-) terminal.
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The gold wire you refer to is a yellow wire by schematic illustration.
I will look for compatible battery illustrations on the web.
I will not say I am right because I normally don't work on tube battery sets, so It would be only my educated guess.To help clarify go to the following link.
It's Phil's Old Radios.
Click Here for battery info.
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