Low cost geiger counters - Page 1
Forum section: electronics / general

author: nidlaX
author_rank: Frequent Contributor
timestamp: January 18, 2018, 01:32:26 pm
content: I'm looking for a Geiger counter with a digital display and preferably some data-logging capability for under $150.Some popular options I've seen include:https://www.ebay.com/itm/New-GQ-GMC-300E-Geiger-Counter-Nuclear-Radiation-Detector-Data-logger-Beta-Gamma/271363879425https://www.ebay.com/itm/RADEX-RD1503-Geiger-Counter-Radiation-Detector-Dosimeter-New-2017-Model/171888709827https://www.ebay.com/itm/Geiger-Counter-Nuclear-Radiation-Detector-Personal-Dosimeter-Marble-Tester-X-ray/263444201697https://www.ebay.com/itm/Compatible-with-Arduino-Geiger-Counter-DIY-Kit-Nuclear-Radiation-Dosimeter/321315968002Any opinions on which models are good / bad?

author: ChrisLX200
author_rank: Unknown
timestamp: January 18, 2018, 03:23:39 pm
content: I have a GMC 300E and it's good value for money for a pre-built gamma/beta counter, it runs 24/7 (mostly anyway - the software I use called RadLog tends to crash farily frequently, but the 300E still runs fine). Visit the RadMon website for more infohttp://www.radmon.org/I also have a kit geiger counter (Arduino based) with a SBT-11A tube (http://www.radmon.org/index.php/kunena/kit-geiger-counters/696-arduino-geiger-counter-bundle-ebay-special) , and a MyGeiger V.3 board also fitted with a SBT-11A tube (http://www.radmon.org/index.php/kunena/kit-geiger-counters/693-mygeiger-v-3-0).What were you intending to do with it? Most of these simple devices are used for monitoring background Gamma radiation, for sample monitoring you should look to use a detector (tube) sensitive to alpha particles too - the SBT-11A is good for that being sensitive to both Alpha and Gamma/beta.

author: nidlaX
author_rank: Frequent Contributor
timestamp: January 19, 2018, 02:09:19 am
content: I'm mostly interested in checking used equipment I buy for contamination, thanks for the links.

author: kathy45
author_rank: Newbie
timestamp: January 19, 2018, 10:57:27 am
content: RADEX RD1503+, You can try this if you want. This thing must be shipped individually from other items in your order. Additional shipping charges will not apply, 2 AAA batteries required. Now displays the difference of the dose rate between the equalized and background values and Combines vibration signal and audio alarm.

author: ChrisLX200
author_rank: Unknown
timestamp: January 19, 2018, 11:31:22 am
content: Quote from: kathy45 on January 19, 2018, 10:57:27 amThat is a beta/gamma only detector and does not offer a connection to an external device (e.g., PC) for data logging. Really it is an exposure meter for those working in high radiation areas.As stated earlier, it's useful to have the ability to test for alpha emitters if you have no idea what kind of contamination you might be dealing with, and that is a function of the detector tube rather than the counter itself. If you need to identify any particular isotope then you need a spectrophotometer to measure the energies of the emitted particles, that gives you a 'fingerprint' of decay products. Many common isotopes you may come across (like americium241 from smoke detectors, and Radium from old luminouswatch/clock faces) are potent alpha emitters and whilst you can still 'detect' them with a gamma/beta detector (some of the decay products are also gamma/beta emtters) you don't get to see the real potential hazard as powerful alpha emitters. Alpha particles are easily stopped by even a sheet of paper (or your skin) but the real danger is inhalation of contaminated dust and once ingested they do great damage.

author: John Heath
author_rank: Frequent Contributor
timestamp: January 19, 2018, 01:41:58 pm
content: Quote from: nidlaX on January 18, 2018, 01:32:26 pmThere are some cell phone that come with a Geiger counter make for the Japan market. That market was driven by resent events with the last tidal wave. For really cheap you can put black tape over a cell camera lens then count the hits. Not the best but it works. Can not remember if it was an apple app or android app? Probably both.

author: nidlaX
author_rank: Frequent Contributor
timestamp: January 19, 2018, 02:26:35 pm
content: Quote from: ChrisLX200 on January 18, 2018, 03:23:39 pmChris, thanks a lot for linking me to radmon, I have a much better idea of the market now. I'm considering purchasing the eBay special with the SMT11A as well as some parts to build my own counter. Do you know of a reliable source for SMT11A tubes? Also, do you have any experience using the ~$20 tube driver board from the Lithuanian eBayer?

author: ChrisLX200
author_rank: Unknown
timestamp: January 19, 2018, 03:14:21 pm
content: Quote from: nidlaX on January 19, 2018, 02:26:35 pmYes, I bought two SBT11a from AnyDevices (https://www.ebay.co.uk/itm/SBT-11-CBT-11A-Pancake-Geiger-Counter-tube-Beta-Gamma-Alpha-for-Dosimeter-NEW/281130143163?epid=2162658066&hash=item4174a98dbb:g:MucAAOxyyeNSL2Mm) and they were genuine SBT-11a - beware some other sellers offering the SBT-11 (i.e., no 'a') as those are far less sensitive to alpha emitters. CBT-11A is Russian spelling for the same tube as SBT-11A. The SBT-11A is an excellent all-round tube and close to the perfomance of others costing many times the amount. The full kit (the Arduino-based counter and SBT-11A tube) is a good choice because it also comes with a tube socket making it much easier to wire up, the tube pins are stainless and otherwise difficult to solder to directly - possible of course, but a fair chance of damaging the tube in the process.The thin mica window on the front is fragile but necessary for detecting alpha particles, you will need to make a protective grille for the front because it is easily damaged. The discrete tube driver board (if it's the one I think you mean, by RH Electronics) is excellent because it allows you to use a long cable between counter and detector tube. He has a website and YouTube channelhttps://www.youtube.com/channel/UC1ftZUdX4Sj_oA5X27fVhDw

author: nidlaX
author_rank: Frequent Contributor
timestamp: January 19, 2018, 03:24:10 pm
content: Quote from: ChrisLX200 on January 19, 2018, 03:14:21 pmUnfortunately, AnyDevices is out of SBT-11As and is only selling SBT-11s now, so I'm still searching for a source. Not sure how reliable SovTubes is.I'm not referring to the driver by RH electronics, but rather by impexeris, the Lithuanian seller of the eBay kit with the SBT-11A. He sells a cheaper driver board:https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F162844726387

author: ChrisLX200
author_rank: Unknown
timestamp: January 19, 2018, 03:45:09 pm
content: Quote from: nidlaX on January 19, 2018, 03:24:10 pmAh, OK. That one is new to me but it appears to be just a high voltage supply for the probe - I don't think it digitises the pulses for return to the counter circuitry (which the RH Electronics one does:http://www.rhelectronics.net/store/high-voltage-geiger-probe-driver-module-380v-550v-with-ttl-output.html). Most counter kits come with a HV supply on the board anyway to drive common tubes (i.e., 4-500v) but the tube needs to be connected close to the HV supply, that is the benefit of the RHE external probe driver module as the actual probe or tube (the SBT-11A in this case) can be located some distance away connected via a cable. In actual fact I've tried connecting an SBT-11A with a 1 metre cable direct to the PCB of an Arduino counter (i.e., no external driver module, wires soldered to the +/- contacts on the PCB) and it does record counts, however the count totals are probably reduced.I'll check if there is an alternative source for SBT-11A's, they are becoming a little scarce these days..Edit: This is the kit I bought, together with SBT-11A and socket. Read down the listing, he is still supplying SBT-11A.http://www.ebay.co.uk/itm/Geiger-counter-dosimeter-kit-assembled-w-SBT11-tube-iR-USB-Arduino-compatible-/162018488365?_trksid=p2349526.m4383.l4275.c10