Solar flashlight (CB20488E)

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

Signal Injector (CB24210E)
Found in the September 1972 issue of Radio Electronics magazine, this signal injector is based on the...
10 W x 2 Ohms Amplifier TDA2003 (CB15716E)
The amplifier presented with the TDA2003 can provide a power of up to 10 W (rms) in a load of 2...
Low current indicator (CB22147E)
We found this circuit in an old English documentation. The idea is a momentary indicator that...