This alarm circuit with NC sensors in series was taken from an article in Radio Electronics magazine from May 1971. The SCR can be any of the 106 series.
The CA3020 integrated circuit was one of the first commercial types, sold in the 1960s. The...
This circuit generates a linear sawtooth signal with frequency that depends on the capacitor next...
This circuit has a maximum frequency of 10 kHz and a linearity better than 0.01%. The circuit is...