High impedance stage (CB20564E)

This high input impedance amplifier stage was found in a 1963 documentation. The transistor germanium of the time.

Old Phonograph Amplifier (CB1416E)
The critical component of this amplifier is the output transformer. We found the circuit in an old...
Power grid Transmitter (CB25181E)
This circuit was found in the January 1989 issue of Radio Electronics magazine. The circuit sends...
Rain Alarm or Door Bell (CB5369E)
This circuit was found in a 1980s documentation. Q1 and Q2 can be BC548 and SCR a TIC106. The...