We found this circuit for 330 MHz using PIC in the magazine Electronics Now of December 1994. The circuit uses components common at the time.
This circuit can measure frequencies up to just over 1 MHz and uses CMOS technology. The circuit is...
This variable oscillator was found in a Mullard transistors manual from 1960. The resistor R5 is...
This circuit, from a 1988 documentation, consists of an automatic temperature control using an NTC...