[ARC5] Battery Tubes

[Robert Eleazer]

Are not the 1 volt filament tubes designed for "instant heating" so that you can push to talk or push to receive (like in a URC-4 or URC-11) and the tubes are not powered up at all until then?  I think the 3Q4 is like that as well.

I am aware of 1 volt filament tubes like the 1L4 used in applications where the filaments were left on all the time, but that would not preclude it being used for instant heating if it was designed that way as well.

I have a couple of RT-70's but it has been a while since I have fooled around with them.  They use 1 volt tubes.  One worked well until the modulation quit and I have not done further troubleshooting.  I got tired of working on it so much, but it never occurred to me to see if the tube filaments were lit all the time or just until you transmitted.

As to John's idea, I would guess you could get a few hammed up URC-4's or -11's and adapt those tubes for a battery powered command set.

Wayne