[BC] Current flow in old radios

[SteveOrdinetz]

Jim Tonne wrote:current.

>The fact is the pilot light was low voltage, 6 volts as I recall.  It
>was placed across a tap on the rectifier filament.  That filament
>had a tap on it just for a pilot lamp, a voltage divider.    But when
>first turned on, the filament string was cold and had lower 
>resistance than when hot.  So there was an inrush of current into
>this series-connected string.  Hence the tap on the filament of the
>rectifier tube (35Z5, etc) delivered more output voltage.  As the
>filament string warmed up the current in the string went down and
>Presto! the voltage to the pilot lamp also went down.
>
>- JimT who unfortunately is old nuff to remember this bit of trivia
>
>(and not alone I suspect . . .)


Alas, no you're not.  :-/
I also seem to recall that if the pilot light burned out & wasn't 
replaced the tube filament went in fairly short order.  What did they 
use for a bulb...somehow a #47 sticks in my head.


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