Radio Battery Eliminator
(High tension supply unit)
Introduced in 1928. The 3003 can provide six
different anode voltages and also three ranges of grid bias voltages that can be adjusted
in steps between 0 and -40 Volts.
The 3003 had
incorrect tubes, one open resistor and a short circuit
capacitor. It is now in working condition. The special
plugs, needed to choose the right grid bias voltages are
still missing, but can be replaced by standard banana
plugs.