The OpenRelief project is building open, modular information solutions for disaster relief , and as part of which they`re developing a range of network-enabled sensors. I offered to help out by prototyping a radiation detector, opting to use an ionisation chamber in favour of a Geiger-Muller tube and constructing this from an old treacle tin. In
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this post I describe the basic principles of operation, before going on to cover early experiences and next steps. The Geiger counter has become synonymous with radiation detection but there are many ways to achieve this other than using a Geiger-Muller (GM) tube. The ionisation chamber works on similar principles to the GM tube, but is an incredibly simple design that can be constructed from an old tin can and which does not require the use of high voltages and an inert gas and halogen fill. You don`t get something for nothing and there are trade-offs, but we`ll come to those later. The inspiration for building an ionisation chamber-based detector came last year around the time of the Fukushima Daiichi nuclear disaster. As fears rose that insufficient information was available to track the spread of leaked radioactive materials, hackers around the world worked on designs for DIY Geiger counters, and those based in Japan made use of the Cosm (formerly Pachube) web service to publish real-time data online. As one might expect there was a run on GM tubes and supplies of those at the cheaper end of the market dried up. Which led me to thinking: why not use an ionisation chamber instead This is essentially little more than an air filled vessel which is open at one end, and with two electrodes across which the flow of current is measured. As radiation such as alpha or beta particles or gamma rays enters the chamber it strips...
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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