The Cossor 41MP is an indirectly heated audio output triode for mains powered receivers. This exhibit is from later production as it is in a classic envelope and considerably smaller than the earlier balloon version of the 41MP.The output load is specified as being 3,000 Ohms and the cathode resistor as being 320 Ohms. The valve through most of the time it was made was designed to produce 1.0 Watt at 5% distortion. In 1929 when the first 41MP's were sold the anode voltage was rated at 185 volts, the anode current as 10.5 mA and the output as 0.23 Watts. For these first valves the grid bias was -9 Volts.The classic envelope is 44 mm in diameter and, excluding the B5 base pins, is 94 mm tall.References: Data-sheet & 1043. Type 41MP was first introduced in 1929. See also 1929 adverts. |