Solar flashlight (CB20488E)

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

Auto repeat timer (CB21425E)
Found in a 1969 British publication, this circuit uses a regenerative switch with two transistors to...
Transistor Tester (CB14958E)
This type of circuit is traditional and has been published several times in different forms and...
MW radio with varicap tunning (CB22172E)
This MW radio circuit with varicap tuning was found in an English documentation from 1989. The...