The original purpose of this circuit, which we find in old American documentation, is to modulate an RF carrier for telecommunications applications. Transistors support equivalents.
Using bipolar, FETs and unijunction this long-lasting timer can reach 10 hours with good quality...
The configuration shown is from the National Semiconductor Linear Applications Handbook. The...
This shield circuit uses a common CMOS port. The voltage depends on the interfaced logic. The...