This timer for photography work was published in Radio Electronics magazine in December 1959. Power comes from the power grid through a transformer source.
This circuit was found in an English magazine from 1979. The magazine no longer exists, but the...
This 2001 CMOS digital circuit draws numbers from 00 to 99 and can be expanded. However, it does...
The sensor in this circuit is a BA315 diode. Other diodes can be experimented, but this is one...