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]

19 thoughts on “More Radiation Test Gear

  1. heh..
    These Russian Geiger tubes seem to show up on ebay a lot, evidently there are lots in storage from the Cold War.

    They typically detect hard beta, gamma and X-rays but this makes them useful for measuring background radiation and they respond well to lantern mantles/etc.

    For detecting alpha and soft (low energy) beta however you need an end window tube or ion chamber.

    I did have an intriguing idea however, integrate a flat geiger tube inside the PCB itself (!) with an ITO coated mica window on top and rely on the copper to make the thing leakproof.

    apparently you can make a chip sizd radiation counter using a MEMS based discharge tube, neodymium magnet and radio receiver, there has been some research into this.

  2. Impressive little device. GPS data logger is a nice touch.

    The use of two tubes is interesting. Most of the old detectors I’ve seen have used one tube inside, and one in a external wand. The internal tube was shielded with some metal to reduce its sensitivity to boring old low power radiation.

    nice toy, very useful for geologists.

  3. I’m told that these Russian tubes use hydrocarbon quenching, a little bit of which is used up at every click.

    The result is that the tubes have a lifetime in terms of clicks – over time the quenching gas is used up and the tubes will stop working.

    American tubes, such as the 6993 available on eBay and used in those old yellow Civil Defense counters (the ones with the wand) use halogen gas for quenching, which does not get used up.

    Interfacing a 6993 to a micro is trivial – put a 2pf in series with the tube, a 1 meg to ground, then clamp the resulting voltage with a pair of diodes. This results in a 20 us pulse.

    You can buy the 6993 tubes for $20 apiece, and an old CDV-700 counter (which already has the HV supply in it) for about $50 on eBay.

  4. A nice project I don’t want to diss it, but using the browser word search function the words calibrate or calibration where not found. IMO any instrument that’s going to attempt to measure the amount of ionizing radiation, calibration is a must. While it to is incapable of piratical calibration for simply indicating an increase of ionizing radiation, the Kearny Fallout Meter, that another mention in the comments to the HaD post yesterday, might be the most expedient for a go or stay decision. I say might because AFIK the KFM was apart of cold war propaganda to make the public feel safe. Then again the physicians for civil defense fell it worthy of mention, I’ll let you visit their site and judge for yourself.

  5. Having spent some time reading more about the Kearney Fall out Meter, and taking what I’m reading at face value, it may be the most expedient option for concerned Japanese citizens. Constructed per instructions,it’s claimed calibration isn’t necessary. Until I read more on this I did realize how many pro limited nuke exchange warfare supporters there are.

  6. Every geiger-counter i’ve seen has tubes filled with gas. Making allmost every version too bulky.
    Isn’t there a solid-state version?
    Something i can clip on that start beeping if the levels become dangerous?

  7. The tubes are old school but SS has been around since the 60’s. Yes it’s possible but still exotic or expensive.
    There is argon or some ionizonable gas and then the halogen to quench the discharge, so halogen alone no go. Plus the bulb has two electrodes, center and side. I checked my childhood junk bin and found one in a fiber tube dated 1953, I should have better luck than I did in junior high when I tried to make one, late 60’s

  8. Gert yes there is a device that alarms on dangerous levels. I use one often its called a Rate alarm. Look up Radiography equipment. I do not believe the medical field uses them. We use them doing industrial radiography. Along with dosimeter’s and survey meters.

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