This circuit is from American documentation from 1970. It can be designed with a BC558 and for the operational, we can use equivalents. The FET can be the BF245.
With a load of 35 ohms this amplifier provides a power of a few tens of milliwatts, but we can use an...
This 1965 General Electric circuit uses a "Thyrector" that is a suppressor of the time. The...
The coil of this transmitter has 4 coils of wire 26 or 28 in the form of 1 cm without core and on it...