This circuit was obtained from a General Electric publication from the 1960s. The transistors are from the time and the circuit produces a 1 kHz signal with 1 V input.
This circuit causes an LED to flash at a frequency determined by the capacitor. The circuit has an...
Found in American documentation from the 90s, this circuit can measure frequencies on a linear...
This frequency modulated light transmitter is from a 1990s documentation. The circuit may use...