Homebrew geiger counter

[mw0uzo]

Made a geiger counter from a kit. It's a MyGeiger kit from RH Electronics.
Its very good!

Inside
10648

Rear of pcb, with LiPo 1100mAh battery, charger and serial to USB converter 'mods' allowing charging from USB and datalogging via USB.
10649

In the case
10650

Almost completed unit
10651

Work to do: Add external detector socket and switch, make alpha pancake detector probe and beta/gamma detector probe.

[N2CHX]

Cool!

[mw0uzo]

Background level log
10652

[WØTKX]

How's that swing on a "Dosy meter"?

[mw0uzo]

Mmmm pickled onions
10653

Oh, wait - thats not pickled onions. Thats Am-241, a strong alpha emitter
10654

Yum, 1.47uSv/hr with a load of plastic in the way, detecting the weak gamma and some of the weak beta that Am-241 gives off
10655

[mw0uzo]

CPM log with Am-241
10656

[N2CHX]

What tube are you using?

[K7SGJ]

Planning a trip to Japan?

[mw0uzo]

What tube are you using?

SBM-20 tube from ebay.

I'm waiting for an Si-15BG pancake detector to arrive to make the alpha probe, might get another SBM-20 to make an additional probe to complete the set, which will also double as an outside monitoring probe.

[mw0uzo]

Planning a trip to Japan?

No, but that would be great to test it all!

I'm going to set up a constant monitoring station with an SBM-20 outside, then feed the readings into a webpage, or submit them to one of the websites that provide a global map of readings. That won't be for a while yet. I have an old laptop that runs a QRSS grabber continuously, so will run this on it.

[wa6mhz]

We will need those quickly here on the West Coast. The Fukiyama (or however it was spelled) radiation is in the water headed this way and is expected to lay waste to the Beaches! Going to be lotsa GLOWING GRUNION!!!! Use that kind of meter to see how HOT the Grunion are!

[mw0uzo]

We will need those quickly here on the West Coast. The Fukiyama (or however it was spelled) radiation is in the water headed this way and is expected to lay waste to the Beaches! Going to be lotsa GLOWING GRUNION!!!! Use that kind of meter to see how HOT the Grunion are!

Yes, you'd need a sensitive pancake detector to pick anything up. Datalogging is a must, as you'll only see contamination as a slight increase from background. If you measured immediately detectable increase in counts, then there would be some considerable contamination there. I have seen reports of seaweed food products showing immediate increase in counts next to a gamma/beta only detector, so yeah there is stuff out there in quantities that would be concerning.

[K7SGJ]

No, but that would be great to test it all!

I'm going to set up a constant monitoring station with an SBM-20 outside, then feed the readings into a webpage, or submit them to one of the websites that provide a global map of readings. That won't be for a while yet. I have an old laptop that runs a QRSS grabber continuously, so will run this on it.

That is really quite an interesting project. Thanks for sharing it.

[mw0uzo]

Pancake detector arrived today. Shame work is in the way :/

[n2ize]

Very interesting. I am a freak for radiation detectors and radioactive stuff. Over the years I scratch built a few radiation detectors using both Geiger tubes and ionization chambres. Mostly used predrawn circuits but modified my own now and then. The only "kit geiger counter I ever built was a Velleman K2645 kit which comes with a small Geiger-Mueller tube for detecting beta and gamma... but no alpha window on the tube, although I can fix that be replacing it with an alpha sensitive tube. It works great but you have to read off radiation levels by counting clicks (beeps). However, I came across a website that demonstrates how it can be modified to include a digital readout. I may try that one of these days.

Just wondering what you use to test your counters. I usually use old radium watches and clocks. I have this one radium pocket watch in particular, an Ingraham Biltmore Radium dollar pocket watch from the 1940's or early 50's (the kind that was once sold for a dollar at drug stores and the counter goes insane clicking away like mad when I put it near the counter. And that is just from the gamma and beta radiation from the decay products. It would go even wilder if I were to remove the watch crystal and place an alpha tube near it.

I also have an old Victoreen 1950's radiological survey meter with the old Civil Defense stickers on it. Instead of a Geiger tube it uses an ionization chambre. It is no good for testing low level radiations. It was designed to read high level radiation, like that which occurs after an atomic bomb goes off. It also needs re calibration as its last re calibration date was 1969. Unfortunately I don't have a nice chunk of radioactive cesium required for calibration. And frankly I am kid of glad, I doubt I would want to keep a chunk of cesium laying round the house.

[mw0uzo]

Very interesting. I am a freak for radiation detectors and radioactive stuff. Over the years I scratch built a few radiation detectors using both Geiger tubes and ionization chambres. Mostly used predrawn circuits but modified my own now and then. The only "kit geiger counter I ever built was a Velleman K2645 kit which comes with a small Geiger-Mueller tube for detecting beta and gamma... but no alpha window on the tube, although I can fix that be replacing it with an alpha sensitive tube. It works great but you have to read off radiation levels by counting clicks (beeps). However, I came across a website that demonstrates how it can be modified to include a digital readout. I may try that one of these days.

Just wondering what you use to test your counters. I usually use old radium watches and clocks. I have this one radium pocket watch in particular, an Ingraham Biltmore Radium dollar pocket watch from the 1940's or early 50's (the kind that was once sold for a dollar at drug stores and the counter goes insane clicking away like mad when I put it near the counter. And that is just from the gamma and beta radiation from the decay products. It would go even wilder if I were to remove the watch crystal and place an alpha tube near it.

I also have an old Victoreen 1950's radiological survey meter with the old Civil Defense stickers on it. Instead of a Geiger tube it uses an ionization chambre. It is no good for testing low level radiations. It was designed to read high level radiation, like that which occurs after an atomic bomb goes off. It also needs re calibration as its last re calibration date was 1969. Unfortunately I don't have a nice chunk of radioactive cesium required for calibration. And frankly I am kid of glad, I doubt I would want to keep a chunk of cesium laying round the house.

:D

I've got an Am-241 source from a smoke alarm, thats it. Not comfortable having anything else really, I know someone who has a collection of very hot radium painted WWII aircraft instrumentation dials, but i don't want that stuff around here. Strong sources :hand:

I have a problem with my pancake detector, maybe you can help. Its working voltage is 390V, the kit generates 400V. Max voltage on the russian datasheet is 420V. When I first start using it, the counts seem normal for a pancake detector 30-60cpm, then they increase slowly over say 30 minutes to 200cpm+. Something is clearly not right. What do you think?

[mw0uzo]

The counts settle down at around 150-175cpm once it has been on for a while.

[kb2vxa]

"...radiation is in the water headed this way and is expected to lay waste to the Beaches! Going to be lotsa GLOWING GRUNION!!!!"

Never mind grunion, EVERYTHING is prey to THE FLESH EATERS!

Seriously, more pr less, I wouldn't worry about radium dials that are really not strong sources. Once upon a time when they were popular I had a Victoreen V-700 CD Geiger counter, they only show a strong count within an inch or so of the face because glass and air are a pretty good shields against alpha (two protons and two neutrons, a helium nucleus) and beta (high energy electron) particles.

[n2ize]

:D

I've got an Am-241 source from a smoke alarm, thats it. Not comfortable having anything else really, I know someone who has a collection of very hot radium painted WWII aircraft instrumentation dials, but i don't want that stuff around here. Strong sources :hand:

I have a problem with my pancake detector, maybe you can help. Its working voltage is 390V, the kit generates 400V. Max voltage on the russian datasheet is 420V. When I first start using it, the counts seem normal for a pancake detector 30-60cpm, then they increase slowly over say 30 minutes to 200cpm+. Something is clearly not right. What do you think?

Are you using the pancake tube on the same circuit that you were using the standard GM tube ? If so did you notice a similar thing happening with the other tube ? Did you measure the voltage across the tube to make sure it remains stable and does not gradually exceed the breakdown voltage of the tube ? Most geiger tubes have a wide plateau region (range of operation voltages) where the count rate varies only slightly with changes in voltage. When the voltage exceeds the breakdown voltage the count rate will rise rapidly with increasing voltage. As I said, the operating range should be fairly wide but, perhaps with "pancake type" GM tubes is is much narrower. Not completely sure.

[mw0uzo]

Are you using the pancake tube on the same circuit that you were using the standard GM tube ? If so did you notice a similar thing happening with the other tube ? Did you measure the voltage across the tube to make sure it remains stable and does not gradually exceed the breakdown voltage of the tube ? Most geiger tubes have a wide plateau region (range of operation voltages) where the count rate varies only slightly with changes in voltage. When the voltage exceeds the breakdown voltage the count rate will rise rapidly with increasing voltage. As I said, the operating range should be fairly wide but, perhaps with "pancake type" GM tubes is is much narrower. Not completely sure.

It doesn't happen with the other tube. The voltage might be too high, but 10V above the recommended voltage? That's not much. I have put an additional 330K resistor in series with the tube and started logging, So far, only a very slow increase in counts, need some more time to see the trend. I really really hope the trend turns out flat...

[mw0uzo]

Seriously, more pr less, I wouldn't worry about radium dials that are really not strong sources. Once upon a time when they were popular I had a Victoreen V-700 CD Geiger counter, they only show a strong count within an inch or so of the face because glass and air are a pretty good shields against alpha (two protons and two neutrons, a helium nucleus) and beta (high energy electron) particles.

The radium painted dial I measured was hot hot hot, geiger counter went nuts next to it. It was an analogue cheap type though with low scale, so not sure what the actual reading was. Now I have this counter with digital display, it would be interesting to take a more accurate measurement.

[mw0uzo]

After some mucking around I changed to a coaxial cable instead of crocodile clips and kept the 330K resistor. Seems to be behaving so far, i'll leave it on for a few hours and see what the counts are like. Then test with the Am-241 source to check that its still able to detect high count rate.

[n2ize]

After some mucking around I changed to a coaxial cable instead of crocodile clips and kept the 330K resistor. Seems to be behaving so far, i'll leave it on for a few hours and see what the counts are like. Then test with the Am-241 source to check that its still able to detect high count rate.

Could be that type of tube has a narrow plateau region. Once you exceed breakdown voltage they go crazy an count rates go way up quickly. ame as for the low end of the operating range. Below a certain voltage count rates suddenly drop off. BTW... on a side note... be careful not to exceed the operating range. If the tube operates in the breakdown range for too long it can be permanentl damaged.

[mw0uzo]

Could be that type of tube has a narrow plateau region. Once you exceed breakdown voltage they go crazy an count rates go way up quickly. ame as for the low end of the operating range. Below a certain voltage count rates suddenly drop off. BTW... on a side note... be careful not to exceed the operating range. If the tube operates in the breakdown range for too long it can be permanentl damaged.

At first I thought I might have damaged it accidentally. The datasheet says its plateau range is 80V, from 360V to 420V. Annoyingly, although the HT voltage is computer controlled, there is no way to adjust!! I might send the kitmaker an email and request that function for a future firmware update. Also, the kit autoranges the time for counts, which initially seems like a good idea, but if you have a load of counts which shortens the sample time, then no counts, you get a spurious low reading. So fixed would be better, certainly for background counts.

[n2ize]

"...radiation is in the water headed this way and is expected to lay waste to the Beaches! Going to be lotsa GLOWING GRUNION!!!!"

Never mind grunion, EVERYTHING is prey to THE FLESH EATERS!

Seriously, more pr less, I wouldn't worry about radium dials that are really not strong sources. Once upon a time when they were popular I had a Victoreen V-700 CD Geiger counter, they only show a strong count within an inch or so of the face because glass and air are a pretty good shields against alpha (two protons and two neutrons, a helium nucleus) and beta (high energy electron) particles.

The alpha radiation definitely won't go far, certainly not past the watch crystal nor through the watch itself. The beta radiation probably won't be completely blocked by the crystal, In many of the less expensive watches the crystal was made from a thin a thin, clear, celluloid plastic. The betas may have a better time making it through that. Of course the gamma radiation that is emanated will make it through the glass and the watch itself. The real danger of radium watches is not so much the assembled watch (heck for many years I wore a radium watch and at times I still do) but when people dissasemble the watch and remove the dial. In many cases the watches are old and the glow paint has deteriorated and is starting tow flake off the hands and the watch face in which case it is easy for a person to accidentally, or carelessly, inhale or ingest some of the radioactive material.

I always wear plastic gloves and a mask when I need to work on one of my old radium watches, particularly if I need to expose the watch face and hands to the outside. After I am done I get rid of the mask, gloves, and thoroughly wash my hands and the work area.

[n2ize]

The radium painted dial I measured was hot hot hot, geiger counter went nuts next to it. It was an analogue cheap type though with low scale, so not sure what the actual reading was. Now I have this counter with digital display, it would be interesting to take a more accurate measurement.

Sounds a lot like what happens when a geiger counter is placed right next to my old Ingraham Biltmore Radium pocketwatch. Back in the 40's and 50's they were sold as cheap dollar pocket watches. They also tick very loud when they are running. Mine no longer glows brightly. Only a very faint glow can be detected if you are in a dark room and have given your eyes ample time to acclimate to the darkness. But the radium is still quite good. And it will be for the next 1000 years. A common misconception with old radium dial watches is that because they no longer glow they are no longer radioactive. Not so. They no longer glow because the activated zinc sulphide has deteriorated. The radium that was mixed in to make the paint is just about as good as when it was made.

[n2ize]

At first I thought I might have damaged it accidentally. The datasheet says its plateau range is 80V, from 360V to 420V. Annoyingly, although the HT voltage is computer controlled, there is no way to adjust!! I might send the kitmaker an email and request that function for a future firmware update. Also, the kit autoranges the time for counts, which initially seems like a good idea, but if you have a load of counts which shortens the sample time, then no counts, you get a spurious low reading. So fixed would be better, certainly for background counts.

Okay, that sounds like a pretty decent sized operating range for a GM tube. If you can figure a way to do it I would see if you can lower the operating voltage. You might achieve better stability. Where did you buy this kit from ? I am interested in buying one. I would like to experiment with it. I hope its available in the USA, if not I could have it shipped from overseas.

[mw0uzo]

Okay, that sounds like a pretty decent sized operating range for a GM tube. If you can figure a way to do it I would see if you can lower the operating voltage. You might achieve better stability. Where did you buy this kit from ? I am interested in buying one. I would like to experiment with it. I hope its available in the USA, if not I could have it shipped from overseas.

http://radiohobbystore.com/diy-geiger-counter-kit-with-nokia-5110-lcd-pic16f876a.html

[mw0uzo]

the SBM-20 is available at a reasonable price on ebay
the pancake detector i have is Si-15BG http://www.ebay.co.uk/itm/281122459741?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

[mw0uzo]

Weirdly, when I jump out the 330K resistor, the count rate doesn't seem to be increasing anymore. I have changed to 100K and test again.

[mw0uzo]

With the 100k, count rate is about 17k with the Am-241 source. Without it is about 20k. I think I will leave it like that and see how stable the background count is. Perhaps it just needed some proper coax. Anyway, I am certainly happy to trade a bit of high CPM accuracy for stability.

[wa6mhz]

Here's a Geiger tube for $26. Not too pricey, seller might be weasible down.
http://www.ebay.com/itm/SBM-20-GM-Tube-Geiger-Counter-Radiation-detector-Dosimeter-US-Seller-/231047806631?pt=BI_Security_Fire_Protection&hash=item35cb85bea7

That unit described in this thread wants these kind of tubes.

here is the kit, but it is a little Pricey, $68, and ships from Israel! Think others sell it for about $40
http://www.ebay.com/itm/Assembled-DIY-Geiger-Counter-Kit-5110-LCD-without-GM-Tube-Arduino-Compatible-/321186186787?pt=BI_Security_Fire_Protection&hash=item4ac8304623

Oh, U have to add an ARDUNIO to it too!

[NQ6U]

Here's a Geiger tube for $26.

Ees gud Soviet tube, da?

[wa6mhz]

tested at Chernobyl

[mw0uzo]

Ees gud Soviet tube, da?

Get out of here stalker.... and visit the lovely Russian Woodpecker
https://www.youtube.com/watch?v=g7mgNTN317M

[n2ize]

With the 100k, count rate is about 17k with the Am-241 source. Without it is about 20k. I think I will leave it like that and see how stable the background count is. Perhaps it just needed some proper coax. Anyway, I am certainly happy to trade a bit of high CPM accuracy for stability.

Even within the operating range different tubes will show different rates depending on voltage. Of course the optimum goal in designing a tube is to get that plateau region as linear and horizontal as possible. The thing is I never tried a "pancake" style GM tube . Since they have a large surface area for collection it could mean greater sensitivity and less of a flat plateau region. And I agree, stability is critical when using it as a long term 24/7 background radiation monitor. Meanwhile it looks like an interesting kit. Thanks for the links. I think I'm going to order myself one this week.

[wa6mhz]

here is another kit, a little cheaper, different display, to think about.
http://radiohobbystore.com/geiger-counter-dosimeter-nuclear-radiation-detector-diy-kit-with-lcd.html

[mw0uzo]

So I left the pancake counter logging overnight, after many hours of normal readings. Here's what I got:

10676

A lot of interesting stuff to note here, and a lot of questions.

The counter was stable for many hours before logging, 25-30cpm average. It was stable until about 4am, at which the rate slowly increased.
Then a spike at exactly 7am, to 180cpm. Don't think it rained. Interesting it was exactly at 7am.
Counts then decreased over about 1hr to 90-100cpm average.
Opening the shack at about 9am to provide ventilation did not have a significant effect on counts.

Is it the detector being unstable? Is it the increase in solar radiation day/night cycle? What was the spike at exactly 7am?
Do I risk the detector being damaged to gain a complete 24hr log to see if the pattern repeats?

[PA5COR]

Any chance there's radon gas in the house?
Only way to test it reliable would be a shielded ( lead) box with a known source in it that gives off a reliable constant source you could measure.
Looks like in the end after the peak it settled to a certain level though.

[mw0uzo]

Any chance there's radon gas in the house?
Only way to test it reliable would be a shielded ( lead) box with a known source in it that gives off a reliable constant source you could measure.
Looks like in the end after the peak it settled to a certain level though.

Yes we are in an area that has radon http://www.ukradon.org.uk/map.php?map=englandwales

I'm going to leave the detector on to see if the counts reduce back to previous levels. If they do then detector/circuit is all OK, so fingers crossed.
I can't find much about it online, but I understand there is a variation in background over the night and day, so that may explain the medium term movement in average.
The spike would be very interesting if its real.

[PA5COR]

We've measured small spikes here from the Fukushima disaster in the Netherlands, that fallout is still circling the earth in the Jetstream.
The UK was hit bad with Chernobyl fallout too, just recently a part of Schotland was given free for sheep productss to be sold again, it took 30 years for the fallout to lower enough to go below the safe treshold for products.

Venting the house after a radon buildup will drop the levels fast too, though your spike might have a different cause.
But looking at the gradual build up and spiking then the drop looks about the same as radon gathering in the house then vented out.
We don't have radon here, all we measure here is background or remnants of the Chernobyl radiation still lingering here measurably and the new added stuff from Fukushima.

Still ongoing now, but soon after the accident the radiation was measured worldwide.
Radioactivity is monitored on a global scale by the International Monitoring system (IMS) radionuclide network, which is being built for the Verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). This network consists of 80 particulate stations. In the period from April to July 2011 (https://na22.nnsa.doe.gov/prod/researchreview/2011/PAPERS/04-15.PDF), more than 40 stations detected radionuclides released from Fukushima NPP and more than 1600 samples contained radiation originating from this event. The data obtained from all stations of the IMS network in the northern hemisphere showed an almost constant ratio of Cs-137 and Cs-134.
Data from the CTBTO network showed that radioactivity from Fukushima was first detected on 12 March at the Takasaki CTBTO monitoring station in Japan indicating that the radioactive plume initially travelled in a south westerly direction. Several gaseous fission products like Cs-134, Cs-136, Cs-137, I-131, I-131, I-133, Te-132, Ba-136m and Xe-133 were detected. Due to the early observation of Te-132 it can be concluded that the fuel in the reactor core was damaged shortly after the earthquake and tsunami
Within 2 weeks the whole northern atmosphere was affected. The radioactive plume next travelled to eastern Russia (14 March) and then crossed the Pacific towards the North American continent to Europe and to Central Asia. The dominant radionuclides were xenon isotopes and especially Xe-133 together with I-131, Cs-134, and Cs-137, and further short-lived radionuclides like Te-132 and I-132 were also detected.
Radioactive material released from Fukushima was detectable all across the northern hemisphere 12 to 15 days after the accident. A CTBTO monitoring station in Iceland detected radioactive isotopes indicating that the plume had reached Europe on 20 March. This was confirmed by European monitoring networks (Masson, et al., 2011). For the first four weeks, the radioactive materials remained confined to the northern hemisphere but by 13 April was detected at stations located in Australia, Fiji, Malaysia and Papua New Guinea indicating that it had reached the southern hemisphere (CTBTO, 2011).

[mw0uzo]

So heres the log up to now
10680

The trend is back down to the low levels seen late last night, not quite there yet but almost.
So tube is likely OK :)

I don't think the readings are due to radon (though the spike could be) as the door to the shack has been open all day.

I have discovered the perfect case for the pancake detector - one of those red plastic wine corkers! Stay tuned.

[mw0uzo]

Finished off the pancake detector probe, made from a plastic wine bottle corker. Perfect end diameter for the pancake tube.
10683

Cable exit made from lucky rubber grommet find, all strengthened and fixed with epoxy
10684

Detector end
10685

[mw0uzo]

I wonder if that extra radiation measured during the day is x-ray emission from the sun? The pancake is fairly sensitive, so could be picking up x rays? I left the SMB-20 hard beta/gamma tube logging overnight and it was flat, so that points to x-rays.

[mw0uzo]

Socket fitted to connect the probe. Internal SBM-20 is removed, not yet decided whether to have an internal tube with switch. I think I might use the SBM-20 to make an outdoor detector and the SI-15BG for all other purposes.

[mw0uzo]

Outdoor / hand gamma probe. Made from a piece of white tube, two plastic wine bottle corks and a random piece of plastic to keep the tube central in the case.
10688
10689

[mw0uzo]

Ok so another problem with the pancake has surfaced, after I put it all together :/
I am getting intermittent high counts. Is it a 'hot particle' wafting around (probably not?) or another problem to solve.
At the moment of high counts, I blew on the surface of the window and the counts stopped. If it was a hot particle, then maybe this could occur one, but several times?
I'm going to try cleaning the window and finding a cap to go over it, then log for ages to see if the problem returns.

[PA5COR]

You can find the odd hot particle wafting around, if it is hot enough to upset the counter that much i doubt.

[mw0uzo]

The counter has been going nuts this evening, I thought the pancake was showing problems again, but swapping over to the sbm-20 showed higher than normal readings too. Outside and inside the house. Counts at the moment are 40-60cpm on the sbm-20 and 60-100cpm on the pancake. They were higher earlier and seem reducing very slowly. A few days ago, the pancake was around 30cpm in the evening. Not sure what it could be, radon I suppose. Not logging unfortunately.

[K7SGJ]

The counter has been going nuts this evening, I thought the pancake was showing problems again, but swapping over to the sbm-20 showed higher than normal readings too. Outside and inside the house. Counts at the moment are 40-60cpm on the sbm-20 and 60-100cpm on the pancake. They were higher earlier and seem reducing very slowly. A few days ago, the pancake was around 30cpm in the evening. Not sure what it could be, radon I suppose. Not logging unfortunately.

You better fetch the lead lined underwear.

The probes you fabricated for the sensors look great. Just goes to show that a little creativity and some odds and ends can go a long way. Well done.

[mw0uzo]

You better fetch the lead lined underwear.

The probes you fabricated for the sensors look great. Just goes to show that a little creativity and some odds and ends can go a long way. Well done.

Thanks, I found a good cap for the pancake. An aluminium volume control knob nicked from a junked amp. Pulled the plastic insert out, a single layer of insulating tape on the inside and it fits perfectly. I'll upload a pic later. I have been surprised at the luck of discovering stuff that could be put together, that never usually happens!

[mw0uzo]

Detector protective cap - an old volume control knob. Glad I didn't throw it away.
10693

[mw0uzo]

Ok it turns out that tube really was faulty, after loads more tests and getting some modified firmware to run it at 385V it still was playing up. So a replacement is on its way along with an SBM-19 large beta/gamma tube.

[mw0uzo]

Got the weblogging of readings working!!! Made my first proper PHP script which handles multiple users, putting logged values into SQL database and pulling them out to draw graphs. Made a C# application to run on the computer connected to the geiger counter to update the script with read values. It was all a bit of a headache, but is working well enough now to post here.

http://www.mw0uzo.co.uk/radmon/radmon.shtml

http://www.mw0uzo.co.uk/radmon/mw0uzo/graphtoday.png (http://www.mw0uzo.co.uk/radmon/radmon.shtml)
http://www.mw0uzo.co.uk/radmon/mw0uzo/graphtoday64.png

[PA5COR]

Very well done!!

[mw0uzo]

Very well done!!

Thanks Cor :) Care to build one? With n2ize and yourself I could put a google map up with the readings on it :D

n2ize - let me know when you've got your kit - i'll send you the application to run on your PC, then update the website with a list of users that you can click on so you can view the history.

[mw0uzo]

Ok, updated it so now multiuser is available from the main webpage. An additional graph is available, with 64 sample moving average, collected over 30 minutes. If this graph increases for any length of time, something has definitely been detected!

[mw0uzo]

oh yeah!!! got google map working with readings for different users, that was annoying. Changed my admin user to Ukraine for testing. Check it out:

http://www.mw0uzo.co.uk/radmon/radmon.shtml

[mw0uzo]

Got the google map working better now and a new user :D

[K7SGJ]

Got the google map working better now and a new user :D

I don't want to stroke your ego, but I am really impressed with all the homebrewing, experimenting, and especially the documenting of what you have done. I spent over 50 years as a component level electronic tech, the last 30 for the government, and have fixed just about every electronic device known to mankind, from DC to light. Other than way early on as a 13 YO ham with no $$, I have never really done much of the scratch building you have posted here; other than having to make things work in applications other than those for which they were designed. I really enjoy following your projects, and the diversity of what you create.

Thanks for all the posts, and sharing the projects from start to finish. I, for one, really appreciate it. Keep on experimenting and posting!!

[mw0uzo]

I don't want to stroke your ego, but I am really impressed with all the homebrewing, experimenting, and especially the documenting of what you have done. I spent over 50 years as a component level electronic tech, the last 30 for the government, and have fixed just about every electronic device known to mankind, from DC to light. Other than way early on as a 13 YO ham with no $$, I have never really done much of the scratch building you have posted here; other than having to make things work in applications other than those for which they were designed. I really enjoy following your projects, and the diversity of what you create.

Thanks for all the posts, and sharing the projects from start to finish. I, for one, really appreciate it. Keep on experimenting and posting!!

:spin:Thank you! There will be more to come.

Just got a new domain for the radiation map working.
www.radmon.org

[mw0uzo]

It rained heavily this morning until this afternoon, so interesting to note the increase in average background radiation during that period. The detector is gamma only, so it is unlikely to detect radon and daughters. However, there is a small increase. I look forward to getting my replacement pancake detector...

10774

[mw0uzo]

Added some more graphs to the userpage of the website and another station is in the pipeline. Hopefully they will be submitting data tomorrow at some point...

n2ize - got your kit yet?

[mw0uzo]

Some progress has been made on the radmon.org website. There are now 9 stations (I'm looking forward to the 10th... been waiting far too long!!) and a forum has been added. Map markers auto update with refresh - that part was fairly hideous to get working. Also RadLog software has got loads of proper features.