This circuit was obtained from an 80's EDN. The components used are still common. The circuit can be used as a shield and the frequency is approximately 775 Hz.
We found this circuit in the Radio Electronics magazine of May 1977. The circuit has the frequency...
This 200 kHz oscillator was found on a 90's EDN. It consumes only 2.8 mW and has CMOS compatible...
This tracker for audio and RF signals was found in old American documentation. Transistors and...