Solar flashlight (CB20488E)

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

XTAL CMOS Oscillator (CB12388E)
This traditional crystal CMOS oscillator circuit was found in a 1990 Electronics Handbook. The...
Electronic Lure (CB14786E)
This version of a call-fish is from 1981 using, for this reason, a 90 V battery that is no longer...
5 mA Essimeter (CB13701E)
This signal strength meter (S-meter) was found in a 1975 amateur radio publication. We can use...