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 very high voltage generator for photographing the aura was found in the special edition of...
With this circuit it is possible to activate relays with negative signals of very low intensity....
This circuit, ideal for those who have signal problems in the UHF band, mainly in the reception of digital...