[Milsurplus] was T2X3; now auto-radio tubes

[WA5CAB at cs.com]

e & Group,

I don't have it in writing but the 1.4V (and 2.8V) ratings for the battery 
tubes was probably to give reasonably decent operation over the discharge cycle 
of the carbon-zinc (LaClanche cell) which has an operating discharge range of 
1.5 to 0.75 volts.  Now why the rating isn't say 1.2V which would be more 
nearly in the center of that range I haven't a clue.

Four of the large Ignition cells were also used to run the filaments of the 
BC-221.

In a message dated 6/25/2004 2:36:31 PM Central Daylight Time, 
ejones at hiwaay.net writes: 
> BTW, there ARE a whole passel of tubes with 1.4v fils: the oldies used in
> battery radios in the 30's-50's.  Their filaments were designed for the
> "A" -sized LeClanche cell, the 1.5 volt monster also used to power
> telegraph/telephone systems.  I recall finding old ones in the battery box 
> aside
> the local L&N railroad; and I used one myself to heat the glow plug in a toy
> aircraft engine.  Ironically, I never used one in a radio!

Robert Downs - Houston
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