This is the receiver for the earlier system published in the August 1988 Radio Electronics magazine. Optical capabilities can be used for extended range.
This simple AM transmitter for very small ranges uses in the original version of the 1970s, a...
The HA2620 integrated circuit used in this comparator is from the 80's, but the setting can be...
Figure 1 shows a circuit than can be used as time stage in timers, and other applications....