This circuit was found in a 1980s Intersil documentation. The integrated circuit used is not common today. The power supply must be symmetrical.
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...