This trimmer or reaper amplifier cuts the signal peaks at a voltage determined by the zener diodes. The gain is given by R1 and R1 and the power supply must be symmetrical from 5 to 15 V.
We found this MW radio in a 1957 Raytheon publication. The transistors can be modern equivalent types...
This circuit has no lock, but it has a very low consumption feature in the standby condition. We...
This circuit is from a Popular Electronics from the 90s. It uses an opto-coupler with SCR directly...