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.
This setting appears other times in this section from other sources. This is from an 80's American...
This digital timer provides timings from 1 minute to 10 hours with indication on a 3-digit...
Signals from 27 MHz to 150 MHz can be produced by this one-transistor oscillator. The frequency...