An idea for re-purposing a kit

I used to sell the Touch Paddle kit:

notice the inter digital traces on the left

http://wb9kzy.com/touchp.htm

It was later replaced by the Touch Switch II and then the current PICPADL kit:

http://wb9kzy.com/picpadl.htm

The original Touch Paddle kit was a resistance based, skin conductivity circuit - a very low active power circuit which could be phantom powered via the dit/dah pullups.

The Touch Switch II and PICPADL were capacitive sensing circuits which work better as paddles but at the cost of higher standby/active current.

Getting back to the Touch Paddle circuit, it was very simple, just the 40107, an 8 pin CMOS IC, along with some caps/resistors and diodes.  The user made contact between the inter-digital fingers on the circuit board to "press" a dit or dah.  I used to fabricate a plastic sandwiched sleeve which fit over the fingers.  I discouraged the user from touching the fingers directly as they had solder-based tinning.  

But I had a thought:  maybe this same circuit could be used as a sensor for water ?  Water (from rain or maybe a pipe leak or a washing machine hose leak) would furnish enough bias to turn on the output when the inter-digital fingers get wet.  The output could then be connected to a Sonalert for the actual alarm.  Phantom power might not work due to water probably being key down rather than an intermittent connection the way Morse code is sent.  The outputs of the IC are open drain which can sink over 100 mA so a fairly loud Sonalert could be used.

I will have to find the prototype and try this out !

Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm