The purpose of this 2000 documentation circuit is to decode SSB (BLU) signals to be audible on communications receivers that do not have this feature. The circuit is for 455 kHz FIs, in which function the crystals are chosen.
This circuit was found in a 1973s Japanese publication. The power transistors used are of the era...
Flybacks are no longer misused. However, if the reader wants to recover an old analog television...
This adjustable source was found in a 1979 documentation, but all components are still common...