Hi Dwayne,

> Is this something that you are doing commercially or is it a personal pro=
ject?

I am trying to make it commercial once it is perfected.

> If this is something that you can share, I'm pretty darned sure that
> there are a whole bunch of us who would be interested in learning how
> your soil moisture sensor works and how we can acquire one for for
> ourselves.  Build, buy a kit, whatever.

It is based on capacitive sensing method. Shipping a kit from India will=20
cost you a packet so it is not feasible.

> I'm interested because I'm looking after my friends house while they
> are on vacation and they have 3 plants that need watering - two large
> plants (small trees, actually) that stand about 6 feet tall, the
> other is a medium-size pot on the table.

You can build it yourself and I will tell you off list.

Hi Sergey,

> Can you share a schematic or a principle how the sensor works?

You can build it yourself and I will tell you off list.

> Usual
> problem with long-term use of water/moisture sensors, as well as anything
> that is in contact with water is corrosion

There is no corrosion since the electrodes are not exposed to the=20
environment. I have coated with clear varnish.

> and build up of "gunk", which is
> in most cases a biofilm of bacteria.  Is you sensor susceptible to that?

The thin film of gunk may not have much bearing on the "bulk" (water=20
with dielectric of 80) capacitive sensing.

Cheers

Ravi
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