This Japanese transistor radio was manufactured in the 1960s in Japan. The circuit of 6 transistors is for the medium wave range and is powered by a 9 V battery.
This transmitter circuit for the 27 MHz band uses 4 common FETs and has the details of the coils...
This circuit was found in a Popular Electronics from the 90's. It can be implemented with...
The transistor of this constant current source may be the BC548 or equivalent. Resistor R2 may be...