Found elsewhere in this section, this circuit mimics the noise of a steam locomotive. This was obtained from an Electronics Today International of the 1980s.
This circuit measures the conductivity of a saline solution, which is affected by the electrolysis effect....
With this circuit it is possible to compare the values of two capacitors in the range of 100pF to...
For triggering with the negative transition of the input signal, the circuit indicated for 0 4047...