The EC903 is a high frequency triode for television front end use. The grid is connected to pins 2 and 6 and these are opposite one another on the base. Similarly the anode is connected to opposing pins 1 and 7. The anode voltage is 100 V and the control grid should be -6 to -2 V.
The construction is substantial for a small signal device. The anode dissipation is 2 watts and this also seems high until one realises that the noise figure is reduced as the anode current is increased. Thus this is a low noise. by valve standards, UHF device and was probably run in a cascode configuration.
The thin glass tube envelope is 17.7 mm in diameter, and excluding the B7G base pins is 36 mm tall.
Absolute Maximum Operating Conditions¶
Updated April 13, 2013. shape:thin.glass.tube construction:all.glass type:triode age:1960.1975 base:b7g heater:6.3v pins:7 pin:1.a pin:2.g1 pin:3.h pin:4.h pin:5.k pin:6.g1 pin:7.a