[ARC5] 6SS7

[Bill Cromwell]

On Wed, 2013-02-06 at 08:55 -0800, john rose wrote:
> In the late to mid 1950's a series of tubes was designed and sold
>  specifically for car radios and ran 12 volts on the plate and heater.
>  At last. Silence! The vibrator was gone! This prompted one wag in the
>  ham magazines at the time to write an article along the line "What?
>  You had to develop a special tube to run with 12v B+? Any tube will
>  run with 12v if you.......". So yes, it is possible the Detrola ran on
>  12v. The R-392 (the lightweight, portable (yeah, right. 52#) version
>  of the R-390 not A) has tubes that run 24v on all plates. There are a
>  lot of 26v heater tubes in that set, the rest 12v in series.

Hi,

I have read testimony from hams who have run some tubes as low as 6
volts on the plates and even less on some subminis in some circuits. 12
and 24 volt B+ seems almost trivial but - there isn't going to be
auditorium filling audio from your receiver AND your transmitter will be
very far below the legal limit! I use cans anyway. I get my nine volt
batteries in six packs - five in series makes about 45 volts and I
frequently do an initial power up of gear in unknown condition with four
to ten of those - just for a quick reality check. The six packs are
cheap enough that I have been running one command receiver on a small
stack of them along with an appropriate heater battery. I am
transitioning to operation with those voltages so I can be on the air
during power failures with reasonably economical battery power - still
using tubes.

73,

Bill  KU8H