Marconi C (Round)
DC Amplifier Triode
1913 (British)

The Marconi/Round Type C was an early soft (gassy) tube used as an rf or audio amplifier. Although difficult to build and use, it had higher gain than the available hard tubes of the period. This tube is marked 2V-TF-50 on the bulb. The early Round tubes were made for Marconi by the Edison Swan Electric Company.


Tube fron Rod Burman collection