DA30 Osram balloon shape DO30 NR56 POVT111 V503 matched quartet audio output triodes

Description

The Osram DA30 is a Power Amplifying Triode for use in the output stage of amplifiers where a considerable undistorted power is required without recourse to the application of high H.T. voltages. 

The principal application of the DA30 is to push-pull amplifiers, in which a pair of valves are employed under condition which allow for a considerable undistorted power output by adjustment of the anode to anode load impedance to a lower value than the normal figure for Class A operation.

About the DA30 data

Filament Volts 4

Filament Current 2 amps

Anode Volts 500

Grid -134

Anode Current 60mA

Anode Dissipation 30 Watts

Mutual Conductance 3.85 mA/V

Matched quartet of lovely Marconi Osram MO/V DA30 balloon collected over the many years!

All in excellent shape, a quartet of DA30 tested with AVO 163 

Osram balloon DA30 tested 57mA 100%

Osram balloon DA30 tested 59mA 100%

Osram balloon DA30 tested 60mA 100%

Osram balloon DA30 tested 57mA 100%