This receiver was found in a Popular Electronics from the 90's. Its different configuration shows a tuning circuit after the tube that works as an aperiodic amplifier. Observe supply voltages.
Suggested by Mullard in a1969 documentation, this circuit generates the erasure signal for tape...
This low noise microphone preamplifier circuit was found in American documentation from the 90s....
This transmitter for modulated radiation can be used as an optical data shield. The maximum...