This circuit doubles the frequency of signals from 10 to 50 MHz. We found it in a 1969 Electronic Design. The components are from the period.
The figure shows how to implement an alarm buzzer in an LM3914 to warn about crossing the scale...
This circuit can act as a shield being controlled by a microcontroller by pin 1 or 2. The...
This circuit was obtained from a 1980's QST magazine. The circuit can generate 1 to 15 MHz signals...