Liquid Sensing Circuits
-
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This.... -
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower..... -
Electronic ignition circuit for the water heater is shown. When you open the faucet, switch K 3V battery, since the charging C2 need room, so VT6 is off, the power supply while.. -
Electric water heater temperature control circuit, with water level indication, temperature and anti-dry, leakage power automatic protection function, safe and reliable. (1) Th.. -
A bridge rectifier and 12-volt regulator powers the MOSFET sensing circuit. The unregulated output of the bridge rectifier operates the drain solenoid via switch SI. The sensor itself is built from two electrodes, one made of copper, the other of lead. In.... -
The main (and only) job of this circuit is to activate a buzzer or a relay, each time the level of humidity takes a specific value. Main stage is a memory based on a flip-flop consisting of gates and IC1a IC1 b. The output of this step activates an.... -
The operation of the circuit is based on the difference in the primary impedance of a transformer when its secondary is loaded and when it is open-circuit. The impedance of the primary of Tl and resistor Rl are in series with the load. The triac's.... -
To calibrate the gauge, connect the battery and press the probes gently into a pot containing a plant that is just on the verge of needing water (stick it in so that only an inch of the probe is left visible at the top). Turn the potentiometer until the "OK".... -
This circuit combines two LTC1043s with a based humidity transducer in a simple charge-pump based circuit. The sensor specified has a nominal 400 pF capacitance at RH = 76%, with a slope of 1.7 pF/% RH. The average voltage across this device must be zero..... -
The sensor circuit is adaptable to different liquids and sensors. The constant-current source drives current through the sensing probe and a fixed resistor.. -
Use this circuit to keep the fluid level of a liquid between two fixed points. Two modes, for filling or emptying are possible by simple reversing the contact connections of Kl. The loads can be either electric motors or solenoid operated valves, operating.... -
The circuit draws so little current that the shelf-line of the battery is the limiting factor. The only current drawn is the leakage of the transistor. The circuit is shown in the form of a water level alarm but by using different forms of probe can act as a.... -
The alarm is built around two audio oscillators, each using two NAND gates. The detection oscillator is gated on by a pair of remote probes. One of the probes is connected to the battery supply, the other to the input of one of the gates. When water flows.... -
The circuit uses four NAND gates of a 4011 package. In each oscillator, while one gate is configured as a straightforward inverter, the other has one input that can act as a control input. Oscillator action is inhibited if this input is held low. The first.... -
The unit consists of a sensor, timer, and electric water pump. The sensor is embedded in the soil, and when dry, the electronics operate the water pump for a preset time. The circuit is composed of a level sensitive Schmitt trigger, variable time monostable,.... -
With SI open the circuit functions as a doorbell. With SI closed, rain falling on the sensor will turn on Ql, triggering Q2 and the thyristor and activating the bell, R4 provides the holding for the thyristor while Dl prevents any damage to the thyristor.... -
This circuit is designed to detect the presence or absence of aqueous fluids. An ac signal generated on-chip is passed through two probes within the fluid. A detector determines the presence of the fluid by using the probes in a voltage divider circuit and.... -
When the water level is low, the probe is out of the water and SCRl is triggered on. It conducts and imposes a heavy load on transformer Tl"s secondary winding. That load is reflected back into the primary, gating triac TRl on, which energizes the load. If.... -
Although many circuits use the varying-capacitance method for checking liquid levels, this simple resistive circuit is much easier to construct. Even a tank of a liquid, such as water, has sufficient conductive salts in solution for this method to work..... -
This monitor uses a common 7 41 amp configured as a comparator and a low cost nontransistor as an output driver. With no liquid detected, a voltage of about 2. 92 V is present in the op amp"s inverting input at pin 2. The 100-KO resistors establish a.... -
The sensor is an RC oscillator in which, a water-absorbent plastic film is the insulator in the capacitive element. The capacitance of the film increases with the amount of water it absorbs from the air, and thus reduces the oscillation frequency. A.... -
A simple bridge rectifier and a 12-V regUlator powers the MOSFET sensing circuit. The unregUlated output of the bridge rectifier operates the drain solenoid via switch S1: The sensor itself is built from two electrodes: one made of copper, -the other.... -
This circuit will power up a water pump when the water reaches a predetermined level. Then it turns itself off when the.. -
Originally, this circuit was used to sense a low-water level in a Christmas tree stand, but the circuit can be use.. -
Running a bath can end in a minor domestic disaster if you forget to turn off the taps in time. This indicator activ.. -
At the heart of the Full-Cup Detector is a 555-oscillator/timer configured to produce a 15-Hz click, until .. -
If you choose to make your own moisture sensor,; this foil pattern should come in handy. A sensor connected to J1 causes S.. -
Using a capacitor sensor to detect a water level is a simple method of sensing. This circuit uses C5, which.. -
When the soil is moist, the LED glows. If the moisture falls below a certain predetermined level, the LED begins to flash. If there is still less moisture, the LED turns off. To calibrate, connect the battery and insert the probe into a container of dry.... -
When the 14B-12B pair opens, 12B is connected to Al's summing point via 13B. The sensor now discharges into the summing point through the 1 µ capacitor. Since the charge voltage is fixed, the average current into the summing point is determined by the.... -
A control two (namely a frequency control two motors) Frequency constant pressure water supply control circuit shown in Figure 5-23. Figure, 1,2 fault output terminal; 6,7 anal.. -
After 3t40V power Sutra T seats is reduced to 6.3V low voltage by VDi - V sulfone full transition rectified. c1 filter provide after - when caution circuit NI/555 operating vol..
New Circuits
-
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of.... -
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is.... -
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to.... -
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
-
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the.... -
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,.... -
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the.... -
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power.... -
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
Popular Circuits
This circuit is actuated by an increase in capacitance between a sensing electrode and the ground...
The circuit behaves like a zener diode over a large range of voltages. The current passing...
This hookup is useful in some house wiring situations, where only two wires are available...
The circuit illustrated here comes to the rescue by sniffing out defective bulbs by capacitively...
Continuous monitoring of the mains voltage is required in many applications such as manual...
Converting periodic waveforms to square waves is an integral part of extracting a clock signal...
Atmel`s application note AVR109 describes a bootloader that uses the UART to communicate FLASH...
Most cars do not have delayed interior lights. The circuit presented can put this right. It...
This article is of interest only to readers whose bicycle lights are powered by a dynamo. The...
The artwork style of the opamp and of the meter face both suggest that is is an ACC design and is...
Programmed Signetics 8223 256-bit PROM is used as alphameric display having five 7-segment digits...
As shown, this simple circuit using a LM311 in the level detector, and with a CMOS analog...