PX25 style PTH25 Marconi Osram CV1046 white ceramic base high efficiency audio output pentodes of the highest quality matched quartet

Description

Marcomi PT25H is a 25 watt pentode

Marconi PT25H gives 10 watts per valve in class A.

The screen is operated at the full line voltage, thus simplifying the maintenance of the constant potential necessary for maximum output.

With a grid bias of only 16 volts, PT25H is easily loaded by microphone or pick up with only one preceding stage.

Filament voltage 4

Filament amp 2

Negative grid -16

Anode volts 400

Screen Volts 300

mA 62

mA/V 6.5

Matched quartet of Marconi PT25H VT46 has been tested at

PT25H VT46 tested 61mA 100% emission

PT25H VT46 tested 62mA 100% emission

PT25H VT46 tested 62mA 100% emission

PT25H VT46 tested 63mA 100% emission