We found this tube receiver in a 1950s Japanese publication. The circuit uses 5 tubes and has an RF amplifier stage for greater sensitivity. The power supply is not shown on the circuit.
This notch filter or reject filter rejects signals of a certain frequency with good selectivity. The...
The purpose of this circuit, which we find in a 1975 radio amateur publication, is to measure the...
The coils of this simple mid-wave radius are wound 28 or 26 on a 12 to 30 cm long ferrite rod and the...