Ionising radiation detector

[MBrej]

Hey, does anyone know of a small ionising radiation detector that can be conencted to a PICAXE? It needs to be small and light, so a standard lab geiger counter would be much too large

Thanks, Matt

 

[eclectic]

Possibilities?

https://extranet.fisher.co.uk/insight2_griffin/mainSearch.do


http://www.philipharris.co.uk/webapp/wcs/stores/servlet/CatalogSearchResultView?storeId=72&catalogId=10501&langId=-1&pageSize=9&beginIndex=0&sType=AdvancedSearch&resultCatEntryType=1&searchType=ALL&filterType=ALL&searchTermScope=1&searchTerm=geiger

or other education suppliers.

e

 

[QuIcK]

correct me if im wrong...
doesnt a smoke detector have a radioactive source, and a detector. smoke particles interrupt the "beam" of particles, and trigger the detector.

might be something to look into:
http://chemistry.about.com/cs/howthingswork/a/aa071401a.htm
http://home.howstuffworks.com/home-improvement/household-safety/fire/smoke2.htm

 

[Andrew Cowan]

Specifically we're looking to detect background cosmic radiation. We're looking for something as light as possible, hopefully under 40 or 50 grams.

A

 

[LizzieB]

http://www.techlib.com has a number of radiation detector/ion chamber projects which may be helpful including the pin diode based design on this page.

 

[boriz]

Is this going up on a balloon? Cool.

They are extremely energetic. I think I read someplace that a single cosmic ray can carry enough energy to lift an average person 1cm in the air. Good luck.

 

[testerrrs]

It will be going up in a high altitude balloon.

Here's the info from the first launch:
http://wiki.ukhas.org.uk/projects:apex-i

 

[Andrew Cowan]

I've phoned Centronic - they're going to phone me back and let me know what they could provide.

A

 

[MFB]

The following free e-book ( www.parallax.com/tabid/567/Default.aspx) has a good description of cosmic ray detector instrumentation in chapter 8.

 

[spong]

Stick one of these in your next balloon

http://www.falconryelectronics.co.uk/merlin.html

Now with added link

 

[Andrew Cowan]

A smilie? Or should there have been a link?

 

[kranenborg]

A relatively simple circuit based on a PIN diode detector is also available on Maxim's application note website: http://www.maxim-ic.com/appnotes.cfm/an_pk/2236 . The functionality of the comparator part as well as the controllable voltage reference for the comparator could possibly be completely covered by the picaxe-20X2 as this one has (will have ;o) a very flexible programmable comparator. The 12V detector voltage may be generated by a voltage tripler/quadrupler based on a PWM-generated signal and a handfull of capacitors and diodes.

Thanks for bringing up the issue, makes me dreaming of a possible PongSat application as already suggested by Womai at the end of the following page: http://www.picaxeforum.co.uk/showthread.php?t=9236&page=4

/Jurjen

 

[testerrrs]

Stick one of these in your next balloon

http://www.falconryelectronics.co.uk/merlin.html

Now with added link

What frequency do those things transmit on? I've looked around the site and can't find it!

Cheers though, looks like a rather good idea.

Edit: Got it, 173 MHz. £100 for the cheapest though, ouch!

 

[MBrej]

A relatively simple circuit based on a PIN diode detector is also available on Maxim's application note website: http://www.maxim-ic.com/appnotes.cfm/an_pk/2236 . The functionality of the comparator part as well as the controllable voltage reference for the comparator could possibly be completely covered by the picaxe-20X2 as this one has (will have ;o) a very flexible programmable comparator. The 12V detector voltage may be generated by a voltage tripler/quadrupler based on a PWM-generated signal and a handfull of capacitors and diodes.

Thanks for bringing up the issue, makes me dreaming of a possible PongSat application as already suggested by Womai at the end of the following page: http://www.picaxeforum.co.uk/showthread.php?t=9236&page=4

/Jurjen

Umm interesting. A little more complicated than the other photodiode circuit, but i assume this one is 'a bit more scientific' (you know what your detecting), if that makes any sense. As for the 12V supply, a very small, low capacity battery could be used, as the current from it is almost nothing.

Anyway, a photodiode or ion chamber looks like the best option, thanks for the ideas so far

Matt

 

[hax]

Velleman do a geiger counter in kit form for gamma rays and high energy Beta.

http://www.vellemanusa.com/us/enu/product/view/?id=350509

 

[manuka]

Quite aside from balloons, I've occasionally considered a small radiation detector could have considerable ground utility in countries with nuclear neighbours. At any time of course Chernobyl style disasters may again occur to spoil ones day.

It's never been that much of an issue however here in nuclear free NZ,but contaminated metallic products could slip thru' however ...