This is the receiver for the earlier system published in the August 1988 Radio Electronics magazine. Optical capabilities can be used for extended range.
Using 555 integrated circuits, this alarm circuit was found in a 90s American documentation. The signal...
The time the output is high (1) of a TLCSSB in the astable configuration depends on Ra and C. The...
This high quality circuit with complementary symmetry was found in an Electronics World of 1966....