Placed near a common receiver, this oscillator is intended to generate a beating signal to receive RTTY or SSB communications. The circuit is from old telecommunications documentation.
In the original version of this 1987 circuit, the loads are lamps, but it can be adapted to drive a...
We found this circuit in a Radio Electronics from the 90s. Transistors admit current equivalents,...
This CMOS frequency meter can measure frequencies up to about 1 MHz with a 3-digit resolution. The circuit is...