1 kHz low pass filter (CB7579E)

This filter can be implemented with almost any operational. The power suppply must be symmetrical.

Power Interface Using Two NPN Transistor (MSB043E)
The circuit bellow uses two NPN transistor to drive heavy loads up to some amperes. The maximum...
Long time delay with PUT (CB9681E)
Found in a 1980s American documentation, this circuit uses programmable unijunction transistors of the time....
FET Switch (CB6725E)
This switched filter was found in the 1969 documentation. The FET should be current-matched and eventually...