Originally this circuit was created to produce synchronism pulses in TV cameras SSTV (Low scan frequency), however it can be adapted for other purposes. The integrated circuits are common TTL.
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...