Found in a 1968 Electronic Design, this circuit makes use of an unusual ultrasonic delay line today.
Found in a Popular Electronics from the 90s, this game can be seen in other configurations on this site. The...
With a 1 500 uFcapacitor this timer can reach times up to one hour. The capacitor must be of good...
This circuit appears in other articles in this section, but it is very interesting. It is a...