Rectangular Oscillator 555 (CB22449E)

This oscillator with different outputs has frequencies selected by the S2 switch in 3 bands. We found it in a Popular Electronics from 1992.

Vswr protection circuit (CB20375E)
This protection circuit for standing waves was found in a manual of high frequency circuits and...
High impedance stage (CB20564E)
This high input impedance amplifier stage was found in a 1963 documentation. The transistor...
Photodiode Amplifier (CB4846E)
This setting appears multiple times on the site from different sources. This is from a 2000 manual...