Tunnel diode simple noise generator (CB23705E)

This circuit was found in Radio Electronics magazine from November 1960. The circuit is powered by a photocell of the time.

5 to 12V Voltage Regulator (CB19001E)
This switched or switched regulator was suggested by Texas Instruments in one of its application manuals....
Crystal Oscillator LM339 (CB17186E)
This is one of the possible configurations using the LM139, 239 or 339 voltage comparators. The...
Strobe 7400 (CB22418E)
In the old original version of this circuit from 1989, the LED is common (we recommend 330-ohm...