The danger always exists, when the fuel gases such as propane or gas are confined to a small area. The alarm of toxic gases figs. 1-45 utilizes a tin-oxide-semiconductor. A coil of thin wire heated by a battery 12 V via IC1 and IC2, which pulses the voltage to the coil of the sensor, saving a significant amount of energy. Diode Zener Dl provides a
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constant voltage to the filament coil sensor. resistance of the sensor reduces the sensor is exposed to toxic gases such as hydrogen, carbon Carbon monoxide and propane. To reduce the resistance of the sensor, the SCR gate voltage increases. When the gate threshold voltage is reached, the SCR fires and a buzzer alarm is activated. Once activated, the bell and the switch S1 should be used to reset the alarm. Since the sensor has a good deal of thermal inertia, S1 must be off or open for about three or four minutes after the initial activation, allowing the sensor to stabilize, thus avoiding false alarms. R7 sensitivity control set to the desired value, before the activation of SCR. The toxic gas alarm is sensitive to less than 100 ppm of carbon monoxide. This alarm is useful for simple gas boats, sheds and cabins. You could save a life. Some of the companies listed in the Appendix to offer plans and kits for various toxic gas sensors.
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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