This optical counter was found in a 1964 Electronics Design. It makes use of an uncommon optocoupler today, using emission lamp and a phototransistor.
Obtained in an Argentine publication from 1973, this circuit sends the signal from a small record...
To divide by an odd number‘ means not only the need for flip-flops, but some additional logic too. The...
The circuit is from an English publication from 1978. In it we have the way to connect a 741,...