This circuit aims to increase the selectivity of receivers whose FI is 455 kHz. The circuit is from 1975 documentation. The transistors can be the modern BF494 equivalents.
This circuit uses only passive components calculated for the desired frequency. We found it in an...
This unijunction relaxation oscillator can be used as a very useful signal injector. The circuit is...
Found in a 1965 Electronic Design, this circuit divides the frequency of a 50 MHz signal by 2. The...