Solar timer (CB20498E)

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

Micro Walk-talkie (CB16775E)
This circuit was found in a 1994 documentation. Its signal is applied to any small integrated...
Electronic Morse Key (CB4196E)
This electronic Morse Key for telegraph message transmission was found in an American 1980s...
AC and DC Full Wave Rectifier LM741 (CB25221E)
This circuit with two operating modes was found in the September 1989 issue of Radio Electronics...