Solar flashlight (CB20488E)

This circuit charges a battery to power a flashlight at night. The circuit is from an English publication from 1991.

Factory and Police Siren (CB18210E)
This circuit produces the sounds of the two types of siren switched by S3. The circuit is from...
Current Regulator 1.5 A L200 (CB15145E)
This circuit was found in the SGS manual of linear integrated circuits of 1982. The integrated circuit...
Operational Multi Ammeter (CB13261E)
The operational amplifier used in this circuit from a documentation from the 70s is no longer easy...