植物缺水告警器,water alarm for plant
植物缺水告警器,water alarm for plant
关键字：缺水告警电路
parts:
r1___________470k1/4w resistor
r2_____________3k3 1/4w resistor
r3___________100k 1/2w trimmer cermet
c1_____________1nf 63v polyester capacitor
c2____________47µf 25v electrolytic capacitor
d1__________1n4148 75v 150ma diode
d2_____________5mm. red led
ic1___________4093 quad 2 input schmitt nand gate ic
p1,p2_______probes (see text)
sw1___________spst slider switch
b1______________3v battery (2 aa 1.5v cells in series)
device purpose:
this circuit is intended to signal when a plant is needing water. a led illuminates at maximum brightness when the ground in the flower-pot is too dry: it dims gradually as the water's content in the pot grows, turning off when the optimum moisture's level is reached. this condition is obtained trimming r3.
circuit operation:
ic1d forms a square wave oscillator with approx. 10/90 mark-space ratio. it feeds the output probe p1 and its signal, inverted by ic1a is compared with that picked-up by p2 in the nand gates ic1b & ic1c in parallel, driving the led. when a low resistance exists between the probes, due to an high water's content in the flower-pot, the led is off, turning gradually on as the resistance between the probes increases.
notes:
a square wave is used to avoid probes' oxidization. probes can be long nails, carbon rods obtained from disassembled exhausted 1.5v batteries, or even a couple of screwdrivers. the probes must be driven in the pot's ground a few inches apart. due to 3v supply, the led needs not a limiting resistor. power consumption: led off = 50µa; led full on = 1ma. to switch-off the circuit, you can short the probes. in this case sw1 can be omitted. using an high-efficiency led, brightness variations are better emphasized. in this case a limiting resistor could be necessary.
解析仿生机器人为了发展方向及趋势
移远通信正式推出两大Wi-Fi 6模组，提供更加高速、安全、稳定Wi-Fi体验
电力超标准电池百万倍的核动力电池研发中
魅族pro7什么时候上市？魅族pro7最新消息：魅族PRO7放大招，双显示屏+双摄，高颜值创新的选择！
TDA6120Q的具有反馈因数1／83的测试电路
植物缺水告警器,water alarm for plant
TS16949与ISQ9000的区别 浅谈TS16949与ISQ9000的不同之处
大屏手机的旗舰对决:三星Galaxy S8与华为Mate9,你选谁?
深度：构建GPT-4模型，如何商业落地？
海克斯康智能制造贯穿制造业全生命周期
紫光国微完成对同芯微电子的增资工商变更登记手续 增资共达9亿元
哪个骨传导耳机比较好用，双十一最值得入手的骨传导耳机
智能控制硬件系统有哪些？
Anolis OS 8.2第二个发行候选版本正式发布
2025年，全球物联网设备的数量将达到386亿台
电流模式控制优缺点
Science杂志评选10项激动人心的机器人开发和技术
中国处于全球制造业第三梯队 仍需努力30年成制造强国
CHA4253AQQG中功率放大器UMS
中国电子产业10大突破 看本土产业如何崛起？
关键字：缺水告警电路
parts:
r1___________470k1/4w resistor
r2_____________3k3 1/4w resistor
r3___________100k 1/2w trimmer cermet
c1_____________1nf 63v polyester capacitor
c2____________47µf 25v electrolytic capacitor
d1__________1n4148 75v 150ma diode
d2_____________5mm. red led
ic1___________4093 quad 2 input schmitt nand gate ic
p1,p2_______probes (see text)
sw1___________spst slider switch
b1______________3v battery (2 aa 1.5v cells in series)
device purpose:
this circuit is intended to signal when a plant is needing water. a led illuminates at maximum brightness when the ground in the flower-pot is too dry: it dims gradually as the water's content in the pot grows, turning off when the optimum moisture's level is reached. this condition is obtained trimming r3.
circuit operation:
ic1d forms a square wave oscillator with approx. 10/90 mark-space ratio. it feeds the output probe p1 and its signal, inverted by ic1a is compared with that picked-up by p2 in the nand gates ic1b & ic1c in parallel, driving the led. when a low resistance exists between the probes, due to an high water's content in the flower-pot, the led is off, turning gradually on as the resistance between the probes increases.
notes:
a square wave is used to avoid probes' oxidization. probes can be long nails, carbon rods obtained from disassembled exhausted 1.5v batteries, or even a couple of screwdrivers. the probes must be driven in the pot's ground a few inches apart. due to 3v supply, the led needs not a limiting resistor. power consumption: led off = 50µa; led full on = 1ma. to switch-off the circuit, you can short the probes. in this case sw1 can be omitted. using an high-efficiency led, brightness variations are better emphasized. in this case a limiting resistor could be necessary.
解析仿生机器人为了发展方向及趋势
移远通信正式推出两大Wi-Fi 6模组，提供更加高速、安全、稳定Wi-Fi体验
电力超标准电池百万倍的核动力电池研发中
魅族pro7什么时候上市？魅族pro7最新消息：魅族PRO7放大招，双显示屏+双摄，高颜值创新的选择！
TDA6120Q的具有反馈因数1／83的测试电路
植物缺水告警器,water alarm for plant
TS16949与ISQ9000的区别 浅谈TS16949与ISQ9000的不同之处
大屏手机的旗舰对决:三星Galaxy S8与华为Mate9,你选谁?
深度：构建GPT-4模型，如何商业落地？
海克斯康智能制造贯穿制造业全生命周期
紫光国微完成对同芯微电子的增资工商变更登记手续 增资共达9亿元
哪个骨传导耳机比较好用，双十一最值得入手的骨传导耳机
智能控制硬件系统有哪些？
Anolis OS 8.2第二个发行候选版本正式发布
2025年，全球物联网设备的数量将达到386亿台
电流模式控制优缺点
Science杂志评选10项激动人心的机器人开发和技术
中国处于全球制造业第三梯队 仍需努力30年成制造强国
CHA4253AQQG中功率放大器UMS
中国电子产业10大突破 看本土产业如何崛起？