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.
We found this active crossover in a Radio Electronics magazine from June 1961. Note the different...
Found in Popular Electronics from the 90s, this circuit serves to indicate the output level of a...
If you are on an old PC that you use for experiments, control or other applications, this circuit is...