We found this circuit in the April 1979 Radio Electronics magazine. Note the filter capacitor bank that can now be replaced by a single equivalent value capacitor.
SST OXY Flex Oxygen Sensor The purpose of this SST sensor is to measure oxygen level in enclosed...
The basic idea of this 1988 circuit is to use a signal called REMOTE existing in some types of...
With each touch on S1, an output of 4017 is activated, this in sequence 3, 2, 4, etc. These...