Solar flashlight (CB20488E)

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

20 MHz Colpitts Oscillator (CB5122E)
This circuit can generate signals in the range from 1 to 20 kHz, depending on the crystal. The...
Two-Phase Oscillator (CB117)
The circuit shown here uses a 4047 to produce three signals whose frequencies are determined by C...
Decade neon counter (CB6618E)
Found in a 1969 documentation, this neon lamp circuit may have the number of steps increased. The power...