Thread: 12 vdc tubes
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Jim Gregory Jim Gregory is offline
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Default 12 vdc tubes


"flipper" wrote in message
...
On Tue, 30 Dec 2008 18:36:01 -0000, "Jim Gregory"
wrote:


"flipper" wrote in message
. ..
On Mon, 29 Dec 2008 10:44:56 +0200, "RealInfo"
wrote:

Hi all

I am looking for old tubes operating on very low voltage , battery
voltage
.
I need them for portabe batery oerated tube preamps .


Any sugestions ?

Thanks
EC


http://www.duntemann.com/12vtubes/12vtubesindex.htm


12V is a lay, 'slang' term. It's actually nearer 14.3V DC.
Jim


Good luck on finding a 'non lay', 'non slang' datasheet that calls a 6
cell lead acid battery anything other than a 12V battery.

12V is nominal voltage and dern close to actual at 50% capacity. At
full charge a "12V" lead acid will be around 12.7V and 10.5V when
discharged.

14.3V would be charging voltage.

In engineering some amount of jabberwocky is necessary but engineers
don't like excesses any more than 'lay' people do and it's a heck of a
lot more convenient to say "12V battery" since, as the saying goes,
"everybody knows what that means," than it is to say "12.7V to 10.5V,
depending on when you look at it and don't forget what happens during
charge, battery."


I stand corrected, but I had meant to say nearer 13V3 DC for a fully-charged
but off-load, Wet battery.
Do Gel batteries, such as fitted to invalids' cars and golf carts, also show
a similar ready, off-load voltage?
Jim