HERF gun zaps more than your dinner


Instructables user [Jimmy Neutron] had an old microwave sitting around and figured he might as well gut it to build a high-energy radio frequency (HERF) gun.

The concept of a HERF gun is not incredibly complex. Much like your microwave at home functions, a high voltage power source is used to drive a magnetron, which produces micro wave radiation at 2.45GHz. These waves are then guided away from the magnetron using a waveguide, towards whatever the target might be. These waves then energize the target in a similar fashion as the water molecules in your food are energized during cooking.

[Jimmy] has not quite finished his HERF gun as he still needs to build a waveguide for it and then safely mount it for use. In the meantime, check out the pair of HERF guns we found in the videos below.

As a parting note, we must stress that building a similar device is dangerous, very dangerous – especially if you do not know what you are doing. Microwaves contain high voltage components, and exposure to microwave radiation can be deadly under certain circumstances. Stay safe!

Looking for more microwave fun? Check these out!

[Read more...]

More radiation test gear

This is a multifunction too for measuring radiation (translated). The measurements center around gas discharge tubes that react when ionizing particles pass through them. After reading about the counting circuit for the pair of tubes used in this handheld it’s easy to understand why these are tricky to calibrate. The handheld features a real-time clock as well as a GPS module. This way, it can not only give a readout of the radiation currently measured, but can record how much radiation exposure has accumulated over time (making this a dosimeter). An accompanying dataset records the location of the exposure. An ATmega128 drives the device, which is composed of two separate boards, a series of five navigation buttons, and a salvaged cellphone LCD for the readout. The translated page can be a bit hard to read at times, but there’s plenty of information including an abundance of schematic breakdowns with accompanying explanations of each.

This is certainly feature-rich and we think it goes way beyond the type of device that Seeed is trying to develop.

[Thanks Andrew]

Seeed looks for help developing an open source radiation detector

Seeed Studios, makers of the Seeeduino and fabricators of small-run PCB orders have put out a call to help develop an open source radiation detector. Will it be of any help to people in the area of Japan that is at risk? We really can’t say. But if you can lend some expertise with this, it can’t hurt. We’ve already seen a simple dosimeter project but this one sounds like it’s more on the level of a DIY Geiger counter. We know it’s possible, but the hacked together unit we saw back in 2007 had very little documentation and used parts that may be hard to come by.

The specific information needed is what type of sensor to use, what supporting circuits should be included, and what method is best to calibrate each unit. There’s a discussion going in the comment thread of that post which should be interesting to read even if you think you don’t have anything to add.

[Thanks Michael]

Monitor UV exposure with your sunglasses

Tired of those awful sunburns? [Nikko Knappe's] UV sensing glasses will warn you before you become crisp and red as a lobster. The bump added to the bridge support hides a TSL230R light frequency sensor. The device automatically switches on when the arms are unfolded and starts tracking cumulative exposure. If it detects a rising UV level, or you are about to burn based on skin type, an LED inside one arm of the frames will flash to inform you.

This has some potential if you think David Brin’s Earth outlines how climate change is really going to play out. Either way it’s still fun and we give bonus points to [Nikko] for disguising the lilypad that controls this as a flowery hair-pin.

Hackable Geiger Counter


[Aaron] A.K.A. [A1ronzo] at SparkFun has put together a hackable USB Geiger Counter. In his tutorial, he gets the Geiger counter to work as a random number generator. Later, he analyzes and discusses how well it works as a random number generator.  In the past, we have seen a number of radiation detectors hacks such as the Mr. Fission digital Geiger counter, a count accumulator, and a Polonium detecting pen,  Besides our inital thoughts of speeding up the number generation, and using it as a special character device, what else can you come up with to do with this device?

Arduino muon detector


[Sebastian Tomczak] was borrowing a homeade muon detector from his friend, and managed to hook it up to his computer through an Arduino. The detector itself uses 3 fluorescent tubes to detect radiation. Three separate tubes are used in order to filter out terrestrial radiation; cosmic radiation will fall in-line with the tubes and pass through at least two of them, whereas terrestrial radiation will only hit one. There is some basic circuitry to amplify the signal and then perform the OR operation.

[Tomczak]  used an Arduino to take the raw data and feed it into his computer. He then used Max/MSP to analyze the data and filter out background noise, leaving only the cosmic ray data. He didn’t mention what he was going to use the data for, though. Maybe he’ll hook it up to a synthesizer.

Related: Digital Geiger counter

[via @littlebirdceo]