To apperceive whether it is freezing you alone charge to admeasurement the temperature. This has to be done accurately, of course, and accordingly we charge to accept a temperature sensor that we accept some aplomb in. The best has afresh been fabricated for a blazon that we accept already acclimated in abounding antecedent Elektor circuits, the L
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M35CZ (-40 to 110 °C). This sensor is not big-ticket and generates an achievement voltage that is proportional to the temperature in degrees Celsius (10 mV/ °C). An LM35 is commonly powered from a single-ended ability accumulation and 0 °C corresponds to an achievement voltage of 0 V. It is accordingly not accessible to admeasurement abrogating temperatures with an LM35 in the accepted appliance circuit. It is about accessible to admeasurement abrogating temperatures if its achievement is affiliated to a abrogating accumulation voltage via a resistor. There needs to be a accepted of 50 A through this resistor (R2 in the schematic). We alone charge to ascertain the freezing point with this circuit. That is why there is a comparator afterwards the temperature sensor, which turns an LED on if the temperature has alone beneath 0 °C during the advance of the night. To ensure that the comparator operates appropriately it is all-important that the altitude amount can become hardly added abrogating with account to the input. To break this problem, a diode (D1) has been affiliated in alternation with the arena affiliation of the LM35. The voltage bead beyond D1 (because of the baby accepted through the LM35 this is alone 0. 47 V) acts as `negative` ability supply. Since the non-inverting ascribe of comparatorIC2 is affiliated via R3 to the anode of D1 it functions as the 0 °C-reference akin for the comparator. The comparator is a...
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.....
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