Solar timer (CB20498E)

This very low consumption circuit can be powered by a solar cell. The time indication is given by a microammeter.

Variable Active Cycle Frequency Doubler (CB5027E)
This circuit was found in an Electronics World magazine from 1990. The circuit can be mounted...
Audio Amplifier LM3900 (CB13834E)
In the figure, from a documentation from the 70s, we have a few-watt amplifier for general use....
Play-Records from the 60s with the CA3020 (CB18500E)
This circuit is from 1968 and consists of an amplifier for turntable of the time. The CA3020 was...