This simple low power triplicator was found in 90’s American documentation. The diodes can be general purpose types and the frequency is determined by the RC network of the 555.
Based on the CA3140 IC, this circuit was found in the June 1986 issue of Radio Electronics....
When sensors X1 and X2 stop driving by the dryness of the monitored location, the oscillator...
This circuit works directly connected to the network and special care must be taken with its...