Homebrew PCBs

On Wednesday 16 April 2003 02:38 pm, Jan Kok wrote:
> From: Stefan Trethan
>
> > just a question: why the hell do you mention 6.3V exactly? seems
> > too high for chem. voltage differential? which reason?
>
> 6.3VAC is a common transformer output voltage (e.g. see Radio
> Shack).  Back in the days of carburetors, vinyl records, mechanical
> adding machines, and Elvis, vacuum tubes used 6.3V (or some
> multiple) on their filaments.
>
> And why was that?  I don't know for sure, but maybe that was the
> nominal voltage of 4 carbon-zinc cells in series.

3 x 2.1V per cell nominal voltage on lead-acid battery.

-- 
Ned Konz
http://bike-nomad.com
GPG key ID: BEEA7EFE