Board-dat/STH/STH1052-dat/STH1052-dat.md
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@@ -17,6 +17,10 @@
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- [[LM393-dat]]
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+
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+
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+
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+
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## Applications, category, tags, etc.
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- [[home-plant-dat]]
Tech-dat/Sensor-dat/sensor-ambient-dat/sensor-moisture-dat/sensor-moisture-dat.md
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@@ -1,93 +0,0 @@
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-
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-# sensor-moisture-dat
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-
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-## board
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-
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-- [[STH1052-dat]] - soil moisture sensor board
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-
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-
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-
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-
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-
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-
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-## working principles
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-
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-The principle of detecting soil moisture is mainly **based on measuring how the presence of water affects the electrical or physical properties of the soil**. The most common types are as follows:
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-
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----
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-
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-### ๐ŸŒฑ 1. Resistive (Conductivity-Based) Principle
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-**Principle:**
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-The more water in the soil, the higher its conductivity (lower resistance) because water contains electrolytes. When the soil is dry, resistance increases.
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-
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-**How it works:**
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-- Two metal probes are inserted into the soil.
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-- A small voltage is applied across them.
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-- The resulting current or resistance is measured and converted to moisture content.
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-
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-**Advantages:** Simple, inexpensive, fast response.
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-**Disadvantages:** Electrodes corrode easily, affected by soil salinity, limited long-term stability.
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-
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----
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-
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-### ๐ŸŒพ 2. Capacitive Principle
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-**Principle:**
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-The dielectric constant of water (~80) is much higher than that of dry soil (~4) or air (~1).
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-As soil moisture increases, the dielectric constant of the soil rises, and the sensorโ€™s capacitance increases.
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-
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-**How it works:**
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-- The sensor forms a capacitor (with metal probes or plates).
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-- The capacitance change is measured and calibrated to indicate moisture level.
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-
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-**Advantages:**
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-- No direct electrical contact with soil (non-corrosive).
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-- High stability, suitable for long-term monitoring.
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-
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-**Disadvantages:**
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-- Slightly higher cost.
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-- Requires high-frequency measurement circuitry.
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-
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----
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-
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-### ๐ŸŒฟ 3. Time Domain Reflectometry (TDR)
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-
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-
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-**Principle:**
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-
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-The propagation speed of an electromagnetic pulse in soil depends on the soilโ€™s dielectric constant, which varies with moisture content.
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-More water โ†’ higher dielectric constant โ†’ slower signal propagation.
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-
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-**How it works:**
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-- A high-frequency pulse is sent along probes.
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-- The reflection time or waveform change is measured.
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-- The dielectric constant is calculated and converted into volumetric water content.
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-
65
-**Advantages:** Very accurate, measures volumetric water content.
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-**Disadvantages:** Expensive and complex equipment.
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-
68
----
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-
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-### ๐Ÿ‚ 4. Neutron Scattering Method (Scientific Use)
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-**Principle:**
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-Fast neutrons are slowed down when they collide with hydrogen atoms (mainly from water molecules).
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-The number of slow neutrons detected indicates the soil water content.
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-
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-**Advantages:** Extremely accurate.
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-**Disadvantages:** Very expensive, requires radioactive sources, strict safety requirements.
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-
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----
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-
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-### โœ… Comparison Table
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-
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-| Type | Measurement Basis | Accuracy | Cost | Stability | Characteristics |
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-|------|--------------------|----------|------|------------|----------------|
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-| Resistive | Conductivity | โ˜…โ˜… | Low | โ˜… | Simple but corrodes easily |
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-| Capacitive | Dielectric constant | โ˜…โ˜…โ˜… | Medium | โ˜…โ˜…โ˜… | Stable, most commonly used |
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-| TDR | Electromagnetic wave velocity | โ˜…โ˜…โ˜…โ˜…โ˜… | High | โ˜…โ˜…โ˜…โ˜…โ˜… | High precision, research use |
87
-| Neutron | Hydrogen atom count | โ˜…โ˜…โ˜…โ˜…โ˜… | Very High | โ˜…โ˜…โ˜…โ˜… | Laboratory / scientific use |
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-
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-
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-
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-## ref
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-
93
-- [[sensor-dat]]
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\ No newline at end of file
Tech-dat/Sensor-dat/sensor-ambient-dat/sensor-soil-dat/sensor-soil-dat.md
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@@ -0,0 +1,12 @@
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+
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+
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+# sensor-soil-dat
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+
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+
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+- [[sensor-soil-moisture-dat]] - [[ph-tester-dat]]
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+
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+- [[sensor-temperature-dat]]
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+
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+## ref
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+
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+- [[sensor-dat]]
... ...
\ No newline at end of file
Tech-dat/Sensor-dat/sensor-ambient-dat/sensor-soil-dat/sensor-soil-moisture-dat/sensor-soil-moisture-dat.md
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@@ -0,0 +1,98 @@
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+
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+# sensor-soil-moisture-dat
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+
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+
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+- [[sensor-soil-dat]]
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+
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+
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+
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+## board
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+
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+- [[STH1052-dat]] - soil moisture sensor board
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+
13
+
14
+
15
+
16
+
17
+
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+## working principles
19
+
20
+The principle of detecting soil moisture is mainly **based on measuring how the presence of water affects the electrical or physical properties of the soil**. The most common types are as follows:
21
+
22
+---
23
+
24
+### ๐ŸŒฑ 1. Resistive (Conductivity-Based) Principle
25
+**Principle:**
26
+The more water in the soil, the higher its conductivity (lower resistance) because water contains electrolytes. When the soil is dry, resistance increases.
27
+
28
+**How it works:**
29
+- Two metal probes are inserted into the soil.
30
+- A small voltage is applied across them.
31
+- The resulting current or resistance is measured and converted to moisture content.
32
+
33
+**Advantages:** Simple, inexpensive, fast response.
34
+**Disadvantages:** Electrodes corrode easily, affected by soil salinity, limited long-term stability.
35
+
36
+---
37
+
38
+### ๐ŸŒพ 2. Capacitive Principle
39
+**Principle:**
40
+The dielectric constant of water (~80) is much higher than that of dry soil (~4) or air (~1).
41
+As soil moisture increases, the dielectric constant of the soil rises, and the sensorโ€™s capacitance increases.
42
+
43
+**How it works:**
44
+- The sensor forms a capacitor (with metal probes or plates).
45
+- The capacitance change is measured and calibrated to indicate moisture level.
46
+
47
+**Advantages:**
48
+- No direct electrical contact with soil (non-corrosive).
49
+- High stability, suitable for long-term monitoring.
50
+
51
+**Disadvantages:**
52
+- Slightly higher cost.
53
+- Requires high-frequency measurement circuitry.
54
+
55
+---
56
+
57
+### ๐ŸŒฟ 3. Time Domain Reflectometry (TDR)
58
+
59
+
60
+**Principle:**
61
+
62
+The propagation speed of an electromagnetic pulse in soil depends on the soilโ€™s dielectric constant, which varies with moisture content.
63
+More water โ†’ higher dielectric constant โ†’ slower signal propagation.
64
+
65
+**How it works:**
66
+- A high-frequency pulse is sent along probes.
67
+- The reflection time or waveform change is measured.
68
+- The dielectric constant is calculated and converted into volumetric water content.
69
+
70
+**Advantages:** Very accurate, measures volumetric water content.
71
+**Disadvantages:** Expensive and complex equipment.
72
+
73
+---
74
+
75
+### ๐Ÿ‚ 4. Neutron Scattering Method (Scientific Use)
76
+**Principle:**
77
+Fast neutrons are slowed down when they collide with hydrogen atoms (mainly from water molecules).
78
+The number of slow neutrons detected indicates the soil water content.
79
+
80
+**Advantages:** Extremely accurate.
81
+**Disadvantages:** Very expensive, requires radioactive sources, strict safety requirements.
82
+
83
+---
84
+
85
+### โœ… Comparison Table
86
+
87
+| Type | Measurement Basis | Accuracy | Cost | Stability | Characteristics |
88
+|------|--------------------|----------|------|------------|----------------|
89
+| Resistive | Conductivity | โ˜…โ˜… | Low | โ˜… | Simple but corrodes easily |
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+| Capacitive | Dielectric constant | โ˜…โ˜…โ˜… | Medium | โ˜…โ˜…โ˜… | Stable, most commonly used |
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+| TDR | Electromagnetic wave velocity | โ˜…โ˜…โ˜…โ˜…โ˜… | High | โ˜…โ˜…โ˜…โ˜…โ˜… | High precision, research use |
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+| Neutron | Hydrogen atom count | โ˜…โ˜…โ˜…โ˜…โ˜… | Very High | โ˜…โ˜…โ˜…โ˜… | Laboratory / scientific use |
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+
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+
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+
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+## ref
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+
98
+- [[sensor-dat]]
... ...
\ No newline at end of file
app-dat/home-plant-dat/home-plant-dat.md
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@@ -8,6 +8,8 @@
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- [[home-plant-dat]] - [[full-spectrum-light-dat]] - [[ph-tester-dat]]
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+- [[sensor-moisture-dat]]
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+
11 13
- [[humidifier-dat]]
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13 15
app-dat/home-plant-dat/ph-tester-dat/ph-tester-dat.md
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@@ -179,6 +179,21 @@ Important: this is not a true pH measurement because the system lacks a glass me
179 179
| Durability | Metals oxidize, especially the non-coated (darker) probe, reducing lifetime |
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+ๅฆ‚ๆžœไฝ ไธ€ๅฎš่ฆ็”จ้‡‘ๅฑžๆฃ’ + ADC๏ผš
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+
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+้“ถๆฃ’ โ†’ ๅฐฝ้‡ๅšๆˆ Ag/AgCl๏ผˆ่กจ้ขๆฐฏๅŒ–๏ผ‰
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+
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+ไธ้”ˆ้’ข โ†’ ไฝœไธบๆต‹้‡็”ตๆž
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+
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+ๅ‰็ซฏๅฟ…้กปๅŠ  ่ถ…้ซ˜้˜ป็ผ“ๅ†ฒ่ฟๆ”พ
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+
190
+็”จ 2โ€“3 ไธชๅทฒ็Ÿฅ pH ็ผ“ๅ†ฒๆถฒๅšๆ กๅ‡†
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+
192
+ๆŽฅๅ— ยฑ1~2 pH ็š„ๅทจๅคง่ฏฏๅทฎ
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+
194
+่ฟ™ไป็„ถ ไธๆ˜ฏๆ ‡ๅ‡† pH ่ฎกใ€‚
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+
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+
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## ref
184 199