On Tue, 27 Aug 2019 09:10:02 -0700, John Robertson
wrote:

On 2019/08/26 11:44 p.m., Phil Allison wrote:
John Robertson wrote:


Indeed, you need to know the tube value to be sure, but consider the
cost of batteries of the day and thus the B+ is likely 45VDC or thereabouts.

In those days some people made their own B+ batteries - way back when I
was a kid digging through attics in Toronto (mid 1960s) for old battery
sets I found a couple of home-made lead acid batteries that were glass
test tubes about 8 inches long mounted in a wooden box and there must
have been 15 to 20 in each case. Wish I still had them as they were
classic home-brew stuff which I always loved from the battery age of radio.



** The "battery age of (tube) radio" extended well into the 1960s.

Popular "portables" of that era used a pair of 45V packs for B+ and a large 1.5V dry cell for tube heaters - all made by "Eveready".

Miniature 7 pin tubes like the 1S4 and 1R5 were used - along with a transformer supply for home use with a multi-finned selenium rectifier.

https://www.radiomuseum.org/tubes/tube_1s4.html



...... Phil


Yeah, but I was talking about the time when the primary home radio was a
battery set - prior to battery eliminators and the like...

I have a lovely (well, it was lovely at one time, the case needs all new
leather) Radiola 24 which was an early 'portable' radio in my small
collection. About the size of carry-on luggage these days. Cunningham
C-299 tubes...

John :-#)#
I had an early 1920s Crosley radio. It had two RCA WD12 tubes which
were retained into their sockets by a rod that projected out of the
tube that was locked into a groove in the tube socket. Tuning was by
a coil on a shaft that one pulled toward or away from a stationary
coil. A multi contact rotary switch selected segments of the AM band.
It used 3 batteries; one for B+, one for the filaments and one for
grid bias. It picked up the 50000 watters in the northeast USA at
night. When I came back home from my first year at a midwest
university, one of my brothers had stolen it and I never saw it again.