Mullard thermionic valve from National Valve Museum:
The 2D4A valve houses a pair of signal diodes with a common cathode. The valve design is from 1934 and the diodes would have been used for demodulation at, probably at around 455 - 500 kHz, the IF frequency of broadcast radio receivers.
- Radio Communication
- Object Number:
- thermionic valve
- component - object
- Gift of Dr. G. R. Airth
- Permanent collection
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