SMT-01 is designed to measure soil moisture and temperature for monitoring and automatic irrigation systems. SMT-01 has a waterproof housing. SMT-01 provides measurement of parameters in a wide temperature range and in soils of different composition with high stability. SMT-01 is compatible with various microcontrollers, and the shielded cable allows data transmission up to 100m. Main technical characteristics: Supply voltage: 3.3 - 5.0 V. Current consumption in measurement mode: less than 150 mA. Standby current consumption: less than 2 mA. Measurement time: 7-12 minutes. Measurement error: less than 2.5%. Sensor dimensions: 40x9x9 mm. Connecting cable length: up to 100 m. The sensor design is based on the dependence of the rate of dissipation of thermal energy on soil moisture. Examples of electrical connection of the sensor and software for Arduino and ESP8266 microcontrollers:
This is commercial, orders can be placed at the email address (see the Github link in first post). The text of the top post is not even made readable, just a big blur of text.
greensensors, I'm sorry, but this is not the place to promote your product. Is your product open source ?
Is it a heating coil with a DS18B20 ?
You lift the temperature about 10 degrees Celsius and then after a few minutes you know how fast the sensor cools down, and that tells something about the soil humidity.
When you have a neat project, we like to hear about it. You can sell it at tindie.com, and you may give a link to it. I would like to test it myself. But you have chosen the wrong way and the wrong forum section. Make it open source and tell us what the price is and how we can buy it.
I have asked the moderators to delete this, but I guess that the moderators are not sure yet.
SMT-01 device is simple and has two main components: 2N2222A - as Нeater and DS18b20 - as Thermometer.
For this reason, the sensor is inexpensive but gives good and stable measurement results.
I have previously tried other methods of measuring soil moisture for the home garden, but this sensor turned out to be the most acceptable. And I thought that maybe this sensor will be of interest to the community. If there is interest, then I think it will be easy to manufacture the required number of sensors.
If you are interested, I can provide additional information on this topic.
That is not open source. I meant to make your sensor open source.
The idea is good, I like it. A transistor as a heater, that idea is very good, it is more reliable than a long thin heating wire.
There is a difference between showing off something that you made after trial and error, or trying to be vague about it and promoting your product in a forum section which is meant for people who ask to solve problems.
Do you know the story of chirp! ? Your sensor could be better, because it can be put deep in the soil.
I have many questions, such as:
How tight are the transistor and the temperature sensor together ? Flat sides to each other ? Glued ?
Can you give a schematic of what is inside ? Is there a resistor for the 2N2222A ?
What do they cost ? I live in Europe, can I order one ?
Do you make each one yourself ?
It is food-safe plastic ?
Did you check the patents ?
Measuring humidity by dissipating heat by the mass of the soil is a scientific method. There are a number of patents that read as : "something with soil and heat". I doubt if any of those is serious.
I am not sending an email to ask for the price. That feels as if I'm lured into something.
Can you make the text of the description at Github and here look better ? It seems to be a big blur of text.
When you look at your top post, there is More/Modify in the lower right corner. You can use that to make changes.
I got some helpful advice from you "Do you know the story of chirp! ? "
and and I will make a complete description of the design of SMT-01 in the next day or two.
I live in Odessa, Ukraine and can send you a sample sensor for free.