This simple logic probe circuit was found in the August 1980 issue of Radio Electronics magazine. The circuit works with both TTL and CMOS logic.
Suggested by Siliconix in 1980s documentation, this circuit uses currently uncommon components. The...
Figure bellow shows how n 4027 can be cascaded to form a divide-by-2. The maximum input frequency...
In the figure we have an interesting protection bridge against power polarity inversion of a...