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.
The critical component of this project from a 1988 publication is the transformer. The final power...
September 2016 – At Mouser is available the new N channel MOSFETs PMGD175NEX from NXP for currents of 950...
This series motor control circuit was obtained from an old manual from the 80's. The SCRs must be...