Half Wave Fast Rectifier (CB5160E)

This 80's circuit can be made with current comparators. Rectification accuracy is 1% DC up to 100 kHz.

High Efficiency LED Flashlight (CB5010E)
I found this circuit in a 2005 Wireless World and it is ideal for driving high power white LEDs....
700 mW amplifier with LM386 (CB966E)
This is one of the many versions of amplifiers with LM386. This was achieved in an old publication (1981). The...
End of Time Warning Timer (CB4673E)
We find this circuit in a 1995 documentation. It warns when the timing is nearing its end, with...