Summary

Electronic valve, Type M8137, manufactured by Mullard for Philips in original packaging. Used as a spare parts for the MUDPAC analogue computer. This valve was used in the second stage of the operational amplifier modules and in the integrator modules. It was a special quality valve, equivalent to the 12AX7 but with more tightly controlled characteristics.

Physical Description

Tubular glass bulb with exhaust tip on top with standard nine pin miniature base. Cardboard box with yellow matt background, blue band and red lines; black, white and blue printed text.

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