Found on a 1964 CQ this circuit is intended for tone frequency change modulation (FSK) telegraphic transmissions. It operates with signals of 2.975 and 2.125 Hz.
With this circuit it is possible to monitor the charge and discharge of a battery. The circuit is...
Found in 90s Radio Electronics, this shield can control high voltage loads in the power grid....
The duration of the output pulse in this circuit depends on C. This capacitor can have values in...