Signal injector (CB21649E)

This circuit was taken from a Popular Electronics from January 1967. Transistors are from the period, but equivalents can be used.

Sampling and Holding with Adjustment (CB20159E)
This circuit is from the factory manual of the LM202, an uncommon operation today. It shows how to...
Negative Resistance Circuit (CB926E)
This configuration presents a negative resistance caracteristic such as the one found in...
Power Oscillator (CB13026E)
The circuit shown in the figure is suggested by National Semiconductor and is based on an...