We found this circuit in a 1964 Electronic Design. It divides the frequency of a 20 MHz signal by 2. The circuit uses a transistor from that time. Details of the coils were not given.
This filter was found in old Raytheon documentation. The circuit makes use of operationals of the time, but...
This circuit uses a ceramic transducer to emit ultrasound whose frequency depends on C2. The...
The integrated circuits used in this project are double equivalents of the well-known 555. The...