> > > > The tubes all have 2V filaments. The radio has two inputs for a > > > > > > filament > > > > supply, 2V or 2.5V (the 2.5V input merely inserts a series > > > > resistor). My > > > > question is....why did anyone manufacture 2V filament tubes and
>Two volt tube were used in the 19 twenties and thirties for FARM radios. They used a 2 volt wet cell. One third of a car battery for those tubes. Also The audio always push pull class B triodes for maximum B battery utilization. Folks carried the cell to the service station or perhaps had a windmill generator from a T model Ford connected for recharging. REA did not start until about 1933 or so and almost no Farmer in America had Electric power. The dry B batteries were 135 volt and lasted a long time but many units had a vibrator pack that ran off a 6 volt wet cell battery from a car or the Edison Electric Company. By the mid 1930's the 230's etc were amost obsolete. Hope this helps HNY, 73 Mike
