This circuit with junction field effect transistors was found in documentation from the 1980s. The transistors can be MPF102 or BF245 and details of the coils are not given in the original.
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...