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.
This 3-transistor timer was found in the January 1994 issue of Electronics Now magazine. The...
This Dimmer circuit for incandescent lamps was found in an English documentation. The input...
With this circuit we can use a high impedance source to excite a low impedance output. The input is...