Where is the Best Place is to Buy a Soil Moisture Sensor That Works Well With Picaxe?

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ZebH
Posts: 96
Joined: Thu May 12, 2016 4:50 pm

Where is the Best Place is to Buy a Soil Moisture Sensor That Works Well With Picaxe?

Post by ZebH » Tue Aug 14, 2018 11:23 am

Hi everyone,

I was wondering where the best place is to buy a Soil Moisture Sensor that works well with Picaxe?

Any help with this would be great!!! :D
~Zeb

~ Andrew
Posts: 32
Joined: Tue Apr 03, 2018 4:35 pm

Re: Where is the Best Place is to Buy a Soil Moisture Sensor That Works Well With Picaxe?

Post by ~ Andrew » Sun Aug 19, 2018 11:01 am

Why buy one when the best one you can make yourself :)

All you need to make this work is 2x Nails and a 10k resistor.
Use
do
readadc 1, b1
debug
wait 1
loop

~ Andrew
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3 Moisture Touch.jpg
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~ Andrew
Posts: 32
Joined: Tue Apr 03, 2018 4:35 pm

Re: Where is the Best Place is to Buy a Soil Moisture Sensor That Works Well With Picaxe?

Post by ~ Andrew » Sun Aug 19, 2018 11:17 am

The next thing you need to do is CALIBRATE this system.
When soil is completely DRY you will get zero or 'NO' reading at all
When soil is completely WET you will get a very HIGH reading
So if you do da science you could calibrate this sytem to make it very accurate like this....
1/. Take 100g of DRY soil and take a reading (it should be ZERO)
2/. WET the soil by soaking it till it can carry NO mmore water and let it drain for say an hour
3/. Weigh the WET soil and it should have 'x' number of grams water in it so it will be 100gm + the water
4/. Let the soil half dry out until it weighs HALF the damp / wet reading 100gm + half the water
5/. Take a reading with the picaxe system as see what it reads
IF you do this kind of thing then you can make a very accurate system.
Any system you buy from a shop will have different readings because it depends on the type of soil, how many chemikills are in it. Making your own system can be more accurate and more usefull to a real growning system.

If you ask I can show you how to make an ADVANCED system using the advanced features of the picaxe ( not available on other micros ). This tech is used by people who sell $1500 system connected to the www, smartiphone, www etc for $15
:)

~ Andrew
~ Andrew

ZebH
Posts: 96
Joined: Thu May 12, 2016 4:50 pm

Re: Where is the Best Place is to Buy a Soil Moisture Sensor That Works Well With Picaxe?

Post by ZebH » Sun Aug 19, 2018 5:17 pm

Thanks so much Mr. Hornblow!!!
~Zeb

~ Andrew
Posts: 32
Joined: Tue Apr 03, 2018 4:35 pm

Re: Where is the Best Place is to Buy a Soil Moisture Sensor That Works Well With Picaxe?

Post by ~ Andrew » Thu Aug 23, 2018 4:20 pm

You will need to do some maths to 'calibrate' the raw reading from the code into meaningful 0 ~ 100 % so let me know if you need help with the maths in picaxe as this can be a bit tricky...
Note that 0 will = max 'dry' = 0 % moisture
some maximum raw number will need some slightly tricky maths to calibrate it so it reads out or displays ~100% when fully wet. But this is possible with picaxe. You just need to multiply UP before dividing DOWN. You can even generate decimal points if needed. Just a few tricks to 'scaling' the numbers.
Here is an example
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ZebH
Posts: 96
Joined: Thu May 12, 2016 4:50 pm

Re: Where is the Best Place is to Buy a Soil Moisture Sensor That Works Well With Picaxe?

Post by ZebH » Thu Aug 23, 2018 7:47 pm

OK thanks very much!!!
~Zeb

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