My Radiascan Radiacode finally arrived from Russia. After the sanctions, I
was surprised to see it made it.

After learning how to operate it, I began to be curious about the low level
background radiation. This is shown in the photo at

https://www.mrmonett.com/RADIACOD.JPG

I wonder what the spectrum curve is saying, particularly the rise and quick
drop near zero. Scouring google, I was unable to find any source that
explained it. What mechanism could produce such weak gamma or x-rays?

Thanks

--
MRM

On 6/5/2022 7:07 PM, Mike Monett wrote:
> My Radiascan Radiacode finally arrived from Russia. After the sanctions, I
> was surprised to see it made it.
>
> After learning how to operate it, I began to be curious about the low level
> background radiation. This is shown in the photo at
>
> https://www.mrmonett.com/RADIACOD.JPG
>
> I wonder what the spectrum curve is saying, particularly the rise and quick
> drop near zero. Scouring google, I was unable to find any source that
> explained it. What mechanism could produce such weak gamma or x-rays?
>
> Thanks

What does the X axis represent?

There's a long decay chain from naturally-occurring thallium 232 and
uranium 238 down to stable lead, and a number of steps in the chain
produce a gamma photon

On 6/5/2022 9:24 PM, bitrex wrote:
> On 6/5/2022 7:07 PM, Mike Monett wrote:
>> My Radiascan Radiacode finally arrived from Russia. After the
>> sanctions, I
>> was surprised to see it made it.
>>
>> After learning how to operate it, I began to be curious about the low
>> level
>> background radiation. This is shown in the photo at
>>
>> https://www.mrmonett.com/RADIACOD.JPG
>>
>> I wonder what the spectrum curve is saying, particularly the rise and
>> quick
>> drop near zero. Scouring google, I was unable to find any source that
>> explained it. What mechanism could produce such weak gamma or x-rays?
>>
>> Thanks
>
> What does the X axis represent?
>
> There's a long decay chain from naturally-occurring thallium 232

Er, Thorium 232, not thallium

On Sunday, June 5, 2022 at 7:07:22 PM UTC-4, Mike Monett wrote:
> My Radiascan Radiacode finally arrived from Russia. After the sanctions, I
> was surprised to see it made it.
>
> After learning how to operate it, I began to be curious about the low level
> background radiation. This is shown in the photo at
>
> https://www.mrmonett.com/RADIACOD.JPG
>
> I wonder what the spectrum curve is saying, particularly the rise and quick
> drop near zero. Scouring google, I was unable to find any source that
> explained it. What mechanism could produce such weak gamma or x-rays?

What do you know of the calibration of the unit itself? Does it have the equivalent of frequency response?

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

On Sunday, June 5, 2022 at 9:25:18 PM UTC-4, bitrex wrote:
> On 6/5/2022 9:24 PM, bitrex wrote:
> > On 6/5/2022 7:07 PM, Mike Monett wrote:
> >> My Radiascan Radiacode finally arrived from Russia. After the
> >> sanctions, I
> >> was surprised to see it made it.
> >>
> >> After learning how to operate it, I began to be curious about the low
> >> level
> >> background radiation. This is shown in the photo at
> >>
> >> https://www.mrmonett.com/RADIACOD.JPG
> >>
> >> I wonder what the spectrum curve is saying, particularly the rise and
> >> quick
> >> drop near zero. Scouring google, I was unable to find any source that
> >> explained it. What mechanism could produce such weak gamma or x-rays?
> >>
> >> Thanks
> >
> > What does the X axis represent?
> >
> > There's a long decay chain from naturally-occurring thallium 232
> Er, Thorium 232, not thallium

When I look at the decay chain, I don't see any gamma emissions. Is this in a more rare decay event?

--

Rick C.

+ Get 1,000 miles of free Supercharging
+ Tesla referral code - https://ts.la/richard11209

On 6/5/2022 10:12 PM, Ricky wrote:
> On Sunday, June 5, 2022 at 9:25:18 PM UTC-4, bitrex wrote:
>> On 6/5/2022 9:24 PM, bitrex wrote:
>>> On 6/5/2022 7:07 PM, Mike Monett wrote:
>>>> My Radiascan Radiacode finally arrived from Russia. After the
>>>> sanctions, I
>>>> was surprised to see it made it.
>>>>
>>>> After learning how to operate it, I began to be curious about the low
>>>> level
>>>> background radiation. This is shown in the photo at
>>>>
>>>> https://www.mrmonett.com/RADIACOD.JPG
>>>>
>>>> I wonder what the spectrum curve is saying, particularly the rise and
>>>> quick
>>>> drop near zero. Scouring google, I was unable to find any source that
>>>> explained it. What mechanism could produce such weak gamma or x-rays?
>>>>
>>>> Thanks
>>>
>>> What does the X axis represent?
>>>
>>> There's a long decay chain from naturally-occurring thallium 232
>> Er, Thorium 232, not thallium
>
> When I look at the decay chain, I don't see any gamma emissions. Is this in a more rare decay event?
>

For thorium the gory details are here:

<https://pubs.usgs.gov/of/2004/1050/thorium.htm>

On 6/5/2022 9:56 PM, Ricky wrote:
> On Sunday, June 5, 2022 at 7:07:22 PM UTC-4, Mike Monett wrote:
>> My Radiascan Radiacode finally arrived from Russia. After the sanctions, I
>> was surprised to see it made it.
>>
>> After learning how to operate it, I began to be curious about the low level
>> background radiation. This is shown in the photo at
>>
>> https://www.mrmonett.com/RADIACOD.JPG
>>
>> I wonder what the spectrum curve is saying, particularly the rise and quick
>> drop near zero. Scouring google, I was unable to find any source that
>> explained it. What mechanism could produce such weak gamma or x-rays?
>
> What do you know of the calibration of the unit itself? Does it have the equivalent of frequency response?
>

For his device it looks like the plot is a histogram of absorbed energy,
and can be set on the 1 MeV, 2 MeV and 3 MeV scales, see top of page 19:

<https://scan-electronics.com/files/EN/RadiaCode/SFX/RC-101_Device_Manual.pdf>

If the widget is set on the 1 MeV scale and the left extreme of the X
axis is about 100 keV and the right hand extreme is about 1 MeV, and the
amplitude on a log plot it seems somewhat congruent with page 4 here:

<https://arxiv.org/ftp/arxiv/papers/1305/1305.2572.pdf>

Seems to be detecting background radiation if that's how it's set up,
situation normal I think?

On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
> My Radiascan Radiacode finally arrived from Russia. After the sanctions, I
> was surprised to see it made it.
>
> After learning how to operate it, I began to be curious about the low level
> background radiation. This is shown in the photo at
>
> https://www.mrmonett.com/RADIACOD.JPG
>
> I wonder what the spectrum curve is saying, particularly the rise and quick
> drop near zero. Scouring google, I was unable to find any source that
> explained it. What mechanism could produce such weak gamma or x-rays?

As a general rule, X-rays excite fluorescences in lots of materials; unless you
have only low-atomic-number elements around, some of those
fluuorescences will be in the low X-ray region, and would presumably be
a low-energy high-count source that penetrates the window of your sensor
(whatever the sensor is). For some sources, secondary radiation
is the easiest to detect (a detector can be transparent to high energy photons).

whit3rd <whit3rd@gmail.com> wrote:

> On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
>> My Radiascan Radiacode finally arrived from Russia. After the
>> sanctions, I was surprised to see it made it.
>>
>> After learning how to operate it, I began to be curious about the low
>> level background radiation. This is shown in the photo at
>>
>> https://www.mrmonett.com/RADIACOD.JPG
>>
>> I wonder what the spectrum curve is saying, particularly the rise and
>> quick drop near zero. Scouring google, I was unable to find any source
>> that explained it. What mechanism could produce such weak gamma or
>> x-rays?
>
> As a general rule, X-rays excite fluorescences in lots of materials;
> unless you have only low-atomic-number elements around, some of those
> fluuorescences will be in the low X-ray region, and would presumably be
> a low-energy high-count source that penetrates the window of your
> sensor (whatever the sensor is). For some sources, secondary radiation
> is the easiest to detect (a detector can be transparent to high energy
> photons).

Thanks for your reply. As a beginner, it is easy to get confused. I'm
confused.

To get more information, I decided to get the spectrum of Potassium-40 by
extending the scale of the Radiacode to 3MV, and sitting it on 3 jars of
Windsor Salt Free shown here:

https://windsorsalt.com/product/salt-free/

Wikipedia gives the following information on Potassium-40 decay:

Potassium-40 is a rare example of a nuclide that undergoes both
types of beta decay. In about 89.28% of events, it decays to
calcium-40 (40Ca) with emission of a beta particle (an electron)
with a maximum energy of 1.31 MeV and an antineutrino. In about
10.72% of events, it decays to argon-40 (40Ar) by electron capture
(EC), with the emission of a neutrino and then a 1.460 MeV gamma
ray.[1] The radioactive decay of this particular isotope explains
the large abundance of argon (nearly 1%) in the Earth's atmosphere,
as well as prevalence of 40Ar over other isotopes. Very rarely
(0.001% of events), it decays to 40Ar by emitting a positron (?+)
and a neutrino.[2]

https://en.wikipedia.org/wiki/Potassium-40

The detector in the Radiacode is a 1 cm cube of Thallium Doped Caesium
Iodide (CsI:TI). This is a very popular scintillation detector and has good
performance when coupled to a avalanch diode.

The Potassium-40 spectrum is here:

https://www.mrmonett.com/POTASS40.JPG

You can see a slight hump at 1.31 MeV and a clearer hump at 1.46 MeV. This
is very satisfying, but it's not clear how the hump at 1.31 MeV is
produced. Is the Radiacode sensitive to beta decay?

Also notice the shelf extending back to zero energy. Where does this come
from?

You mentioned above "X-rays excite fluorescences in lots of materials".

But the sources are presumably beta and gamma. Where is the fluorescence
coming from?

Thanks for your help!

--
MRM

On 6/6/2022 6:38 AM, Anthony William Sloman wrote:
> On Monday, June 6, 2022 at 11:36:51 AM UTC+2, Mike Monett wrote:
>> whit3rd <whi...@gmail.com> wrote:
>>
>>> On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
>>>> My Radiascan Radiacode finally arrived from Russia. After the
>>>> sanctions, I was surprised to see it made it.
>>>>
>>>> After learning how to operate it, I began to be curious about the low
>>>> level background radiation. This is shown in the photo at
>>>>
>>>> https://www.mrmonett.com/RADIACOD.JPG
>>>>
>>>> I wonder what the spectrum curve is saying, particularly the rise and
>>>> quick drop near zero. Scouring google, I was unable to find any source
>>>> that explained it. What mechanism could produce such weak gamma or
>>>> x-rays?
>>>
>>> As a general rule, X-rays excite fluorescences in lots of materials;
>>> unless you have only low-atomic-number elements around, some of those
>>> fluuorescences will be in the low X-ray region, and would presumably be
>>> a low-energy high-count source that penetrates the window of your
>>> sensor (whatever the sensor is). For some sources, secondary radiation
>>> is the easiest to detect (a detector can be transparent to high energy
>>> photons).
>> Thanks for your reply. As a beginner, it is easy to get confused. I'm
>> confused.
>>
>> To get more information, I decided to get the spectrum of Potassium-40 by
>> extending the scale of the Radiacode to 3MV, and sitting it on 3 jars of
>> Windsor Salt Free shown here:
>>
>> https://windsorsalt.com/product/salt-free/
>>
>> Wikipedia gives the following information on Potassium-40 decay:
>>
>> Potassium-40 is a rare example of a nuclide that undergoes both
>> types of beta decay. In about 89.28% of events, it decays to
>> calcium-40 (40Ca) with emission of a beta particle (an electron)
>> with a maximum energy of 1.31 MeV and an antineutrino. In about
>> 10.72% of events, it decays to argon-40 (40Ar) by electron capture
>> (EC), with the emission of a neutrino and then a 1.460 MeV gamma
>> ray.[1] The radioactive decay of this particular isotope explains
>> the large abundance of argon (nearly 1%) in the Earth's atmosphere,
>> as well as prevalence of 40Ar over other isotopes. Very rarely
>> (0.001% of events), it decays to 40Ar by emitting a positron (?+)
>> and a neutrino.[2]
>>
>> https://en.wikipedia.org/wiki/Potassium-40
>>
>> The detector in the Radiacode is a 1 cm cube of Thallium Doped Caesium
>> Iodide (CsI:TI). This is a very popular scintillation detector and has good
>> performance when coupled to a avalanch diode.
>>
>> The Potassium-40 spectrum is here:
>>
>> https://www.mrmonett.com/POTASS40.JPG
>>
>> You can see a slight hump at 1.31 MeV and a clearer hump at 1.46 MeV. This
>> is very satisfying, but it's not clear how the hump at 1.31 MeV is
>> produced. Is the Radiacode sensitive to beta decay?
>>
>> Also notice the shelf extending back to zero energy. Where does this come
>> from?
>
> ""In about 89.28% of events, it decays to calcium-40 (40Ca) with emission of a beta particle (an electron) with a maximum energy of 1.31 MeV and an antineutrino."
>
> The neutrino was pretty much invented to explain why the electron came out with a range of energies - the neutrino carried away the rest of the energy.

And in the more modern physics it helps conserve spin and lepton
number/flavor, they're on the lookout for something like muon ->
electron + gamma where the energies are correct but lepton flavor
conservation is violated. Haven't seen it yet AFAIK

>> You mentioned above "X-rays excite fluorescences in lots of materials".
>>
>> But the sources are presumably beta and gamma. Where is the fluorescence coming from?
>
> Fluorescence can also be excited by energetic electrons - "beta rays". Gamma ray is just another name for an X-ray. It took a while for us to understand that they were both energetic photons.
>

I think in particle physics all photons that come from decay tend to be
called "gamma" even if they overlap with the X-ray's domain below about
100 keV.

At the bottom of page 4:

<http://www-odp.tamu.edu/publications/tnotes/tn26/CHAP5.PDF>

"About 90% of the counts come from the low-energy part of the
spectrum, which is degraded by Compton scattering." I think this means
the area around 100 keV in the background radiation is very noisy with
contributions from the scattered photons of lots of stuff.

On 06/06/2022 03:12, Ricky wrote:
> On Sunday, June 5, 2022 at 9:25:18 PM UTC-4, bitrex wrote:
>> On 6/5/2022 9:24 PM, bitrex wrote:
>>> On 6/5/2022 7:07 PM, Mike Monett wrote:
>>>> My Radiascan Radiacode finally arrived from Russia. After the
>>>> sanctions, I
>>>> was surprised to see it made it.
>>>>
>>>> After learning how to operate it, I began to be curious about the low
>>>> level
>>>> background radiation. This is shown in the photo at
>>>>
>>>> https://www.mrmonett.com/RADIACOD.JPG
>>>>
>>>> I wonder what the spectrum curve is saying, particularly the rise and
>>>> quick
>>>> drop near zero. Scouring google, I was unable to find any source that
>>>> explained it. What mechanism could produce such weak gamma or x-rays?
>>>>
>>>> Thanks
>>>
>>> What does the X axis represent?

Energy I presume. There will be a mix of elements contributing to the
background and some will have characteristic lines. Potassium nitrate or
instant coffee may have enough K40 in to allow some calibration.

https://gammaspectacular.com/blue/k-40-gamma-spectrum#
>>>
>>> There's a long decay chain from naturally-occurring thallium 232
>> Er, Thorium 232, not thallium
>
> When I look at the decay chain, I don't see any gamma emissions. Is this in a more rare decay event?

No they are common but they occur in conjunction (shortly after) either
an alpha or beta decay due to the recoil and necessary rearrangement of
the remaining components of the atomic nucleus.

Just after the alpha or beta particle escapes the nucleus is in an
excited state with a hole in it where the emitted particle once sat.
Gamma ray(s) get emitted as it rearranges back to its new ground state.

Only emissions that alter the atomic number and/or mass are normally
shown on decay chain diagrams.

--
Regards,
Martin Brown

On 6/6/2022 4:24, bitrex wrote:
> On 6/5/2022 7:07 PM, Mike Monett wrote:
>> My Radiascan Radiacode finally arrived from Russia. After the
>> sanctions, I
>> was surprised to see it made it.
>>
>> After learning how to operate it, I began to be curious about the low
>> level
>> background radiation. This is shown in the photo at
>>
>> https://www.mrmonett.com/RADIACOD.JPG
>>
>> I wonder what the spectrum curve is saying, particularly the rise and
>> quick
>> drop near zero. Scouring google, I was unable to find any source that
>> explained it. What mechanism could produce such weak gamma or x-rays?
>>
>> Thanks
>
> What does the X axis represent?
>
> There's a long decay chain from naturally-occurring thallium 232 and
> uranium 238 down to stable lead, and a number of steps in the chain
> produce a gamma photon
>
>
>
>

X-axis should be energy, the spectrum looks right for it to be that.
Clearly with such a device you won't see much energy resolution,
probably the 1461 keV line of 40K won't be visible even if it were
within the energy range of the device (probably not, by the size of it
the detector would be too small for that; buy a kilogram of bananas and
measure it to see if that's the case).
Here is what the 40K peak looks like (the marker, a red X, is on top
of it): http://tgi-sci.com/tgi/nmc3spc.htm#nmc3demo

If the banana pack yields higher counts per second and no visible peak
(which is what I expect you will see) it will be due to Compton etc.,
others may be more familiar with the details, I just design the
spectrometers and have learnt only as much as it takes to do the
measurement and the evaluation of the spectra....

======================================================
Dimiter Popoff, TGI http://www.tgi-sci.com
======================================================
http://www.flickr.com/photos/didi_tgi/

In article <d14769a6-4607-49b7-b2c3-0f9e5312bacen@googlegroups.com>,

>> I wonder what the spectrum curve is saying, particularly the rise and quick
>> drop near zero. Scouring google, I was unable to find any source that
>> explained it. What mechanism could produce such weak gamma or x-rays?
>
>As a general rule, X-rays excite fluorescences in lots of materials; unless you
>have only low-atomic-number elements around, some of those
>fluuorescences will be in the low X-ray region, and would presumably be
>a low-energy high-count source that penetrates the window of your sensor
>(whatever the sensor is).

Correct. In fact, when building high-quality isolation chambers for
measuring gamma specta (the gamma equivalent of a Faraday cage, in
effect) it's necessary to use a layered approach. The outer layer is
usually lead, but when gammas from outside hit the lead it will
fluoresce in the X-ray spectrum. So, inside the lead, you have
another layer which effectively absorbs those X-rays... and *it* may
fluoresce at a lower-energy X-ray frequency, so you may need a third
layer of yet another material.

I've used a home-made gamma spectrometer (NaI crystal, a PMT, and my
own electronics) to look at some naturally-occurring radioactive
materials. One interesting source is some monazite sand from a local
beach - it has a significant amount of thorium in the mix and I get an
appreciable count rate if I lower the sensor down onto a big box of
the stuff.

The spectrum does show the expected gamma-ray peaks for thorium, but
they're not as "clean" as for a purer thorium sample and there's a
strong continuum of lower-energy gamma/X-rays just as the OP's photo
showed. My understanding is that this is "degraded" gamma - in other
words, gamma-induced fluorescence occurring within the sample itself.
Reducing or eliminating this requires flattening out the sample (so
that there's a better chance for a thorium-generated gamma to hit the
NaI sensor before it hits an atom of the sand and causes
fluorescence).

One spectrum I looked at was that of a "quantum energy pendant" that
can be bought inexpensively on eBay and elsewhere. It's supposedly a
natural negative-ion source with semi-mystical healing powers. What
it actually seems to be is a pendant made from a natural ore rich in
thorium. It emits "negative ions" in the form of beta-decay
electrons, and reportedly its emission rates are high enough that if
you wear it next to your skin every day you'd exceed certain government
safety limits for ionizing-radiation exposure in that area (possible
cancer risk or a localized radiation burn).

http://www.radagast.org/~dplatt/gamma/quantum-pendant.png

The green trace is the background radiation level in my work
area. The purple trace is from sampling for the same amount
of time, with the pendant in contact with the NaI sensor. The
thorium-228 peak is clear, there's another from lead and radium
decay daughters, and the actinium-228 peak is also visible.

With another sensor and voltage setting, the background signal
from potassium-40 is visible... and bringing a bottle of
Morton "lite salt" or a bag of water-softener potassium
chloride around the sensor really makes it obvious!

On 6/5/2022 11:54 PM, Anthony William Sloman wrote:
> On Monday, June 6, 2022 at 1:07:22 AM UTC+2, Mike Monett wrote:
>> My Radiascan Radiacode finally arrived from Russia. After the sanctions, I
>> was surprised to see it made it.
>>
>> After learning how to operate it, I began to be curious about the low level
>> background radiation. This is shown in the photo at
>>
>> https://www.mrmonett.com/RADIACOD.JPG
>>
>> I wonder what the spectrum curve is saying, particularly the rise and quick
>> drop near zero. Scouring google, I was unable to find any source that
>> explained it. What mechanism could produce such weak gamma or x-rays?
> How about
>
> https://en.wikipedia.org/wiki/Potassium-40
>
> I seem to remember that it is the most important gamma ray source in regular terrestrial environments.
>
  Yep, used to built bore hole equipment that explored what layers were
below.
One piece was a gamma ray detector. This description doesn't mean much
to me anymore,
if it ever did, but but here are some down hole gamma graphs.
> https://www.kgs.ku.edu/Publications/Bulletins/LA/03_gamma.html

                               Mikek

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
> My Radiascan Radiacode finally arrived from Russia. After the sanctions, I
> was surprised to see it made it.

This listing is also very interesting:

https://www.ebay.com/itm/194659036410

Basically 2000+ PMT+CsI(Tl) assemblies for sale at around $20 each.
Wonder how they'd compare to the solid-state CsI(Tl) detector assembly
in the Radiacode unit?

-- john, KE5FX

On 6/12/2022 22:19, John Miles, KE5FX wrote:
> On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
>> My Radiascan Radiacode finally arrived from Russia. After the sanctions, I
>> was surprised to see it made it.
>
> This listing is also very interesting:
>
> https://www.ebay.com/itm/194659036410
>
> Basically 2000+ PMT+CsI(Tl) assemblies for sale at around $20 each.
> Wonder how they'd compare to the solid-state CsI(Tl) detector assembly
> in the Radiacode unit?
>
> -- john, KE5FX

This is incredibly cheap indeed. I thought even Hamamatsu can't make
PMT-s that small :). (4 years ago they sold us some of their R12421 at
450 euro each IIRC).
But just the scintillation crystal would probably cost much more,
let alone the PMT at Hamamtsu.... No idea how they manage that.

"John Miles, KE5FX" <jmiles@gmail.com> wrote:

> On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
>> My Radiascan Radiacode finally arrived from Russia. After the
>> sanctions, I was surprised to see it made it.
>
> This listing is also very interesting:
>
> https://www.ebay.com/itm/194659036410
>
> Basically 2000+ PMT+CsI(Tl) assemblies for sale at around $20 each.
> Wonder how they'd compare to the solid-state CsI(Tl) detector assembly
> in the Radiacode unit?
>
> -- john, KE5FX

I tried to order one. Does not ship to Canada. Can you order one and mail it
to me? I can pay you via Paypal. Thanks.

--
MRM

On a sunny day (Sat, 25 Jun 2022 18:16:39 -0000 (UTC)) it happened Mike Monett
<spamme@not.com> wrote in <XnsAEC1913D785B5idtokenpost@144.76.35.252>:

>"John Miles, KE5FX" <jmiles@gmail.com> wrote:
>
>> On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
>>> My Radiascan Radiacode finally arrived from Russia. After the
>>> sanctions, I was surprised to see it made it.
>>
>> This listing is also very interesting:
>>
>> https://www.ebay.com/itm/194659036410
>>
>> Basically 2000+ PMT+CsI(Tl) assemblies for sale at around $20 each.
>> Wonder how they'd compare to the solid-state CsI(Tl) detector assembly
>> in the Radiacode unit?
>>
>> -- john, KE5FX
>
>I tried to order one. Does not ship to Canada. Can you order one and mail it
>to me? I can pay you via Paypal. Thanks.

I just found this on tomshardware.com:
https://www.tomshardware.com/news/raspberry-pi-pico-detects-radiation
nice spectra (github link)
https://github.com/Open-Gamma-Project/Open-Gamma-Detector

On Saturday, June 25, 2022 at 11:16:45 AM UTC-7, Mike Monett wrote:
> I tried to order one. Does not ship to Canada. Can you order one and mail it
> to me? I can pay you via Paypal. Thanks.

Maybe. I'll have to surf through the Commerce and ITAR lists to see if there's
a reason why the seller doesn't ship to Canada. Shifty folk, Canadians.

(It'll be a few days before I have time to deal with it, for various reasons.)

-- john, KE5FX

"John Miles, KE5FX" <jmiles@gmail.com> wrote:

> On Saturday, June 25, 2022 at 11:16:45 AM UTC-7, Mike Monett wrote:
>> I tried to order one. Does not ship to Canada. Can you order one and
>> mail it to me? I can pay you via Paypal. Thanks.
>
> Maybe. I'll have to surf through the Commerce and ITAR lists to see if
> there's a reason why the seller doesn't ship to Canada. Shifty folk,
> Canadians.
>
> (It'll be a few days before I have time to deal with it, for various
> reasons.)
>
> -- john, KE5FX

That's fantastic. Thanks.

A lot of US vendors don't want to ship to Canada. But the majority do ship
with no problem. Spending time to find out why may give mixed results. I
can probably ask the vendor what his reasons are. In the meantime, my main
goal is to get a copy of his model before he runs out or gives up.

I will send my name and address to your gmail address. Again, thanks.

Mike

--
MRM

Mike Monett wrote:
> "John Miles, KE5FX" <jmiles@gmail.com> wrote:
>
>> On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
>>> My Radiascan Radiacode finally arrived from Russia. After the
>>> sanctions, I was surprised to see it made it.
>>
>> This listing is also very interesting:
>>
>> https://www.ebay.com/itm/194659036410
>>
>> Basically 2000+ PMT+CsI(Tl) assemblies for sale at around $20 each.
>> Wonder how they'd compare to the solid-state CsI(Tl) detector assembly
>> in the Radiacode unit?
>>
>> -- john, KE5FX
>
> I tried to order one. Does not ship to Canada. Can you order one and mail it
> to me? I can pay you via Paypal. Thanks.

For any serious use, I'd budget for a replacement PMT. They age out
after several years, which is probably why these assemblies were
replaced. They also wear out on account of photocurrent--the usual rule
is that you can get an integrated anode charge of about 1000 C/cm**2 of
photocathode area before the gain drops by ~half.

If you're going to use an ionic scintillator in contact with an end-on
PMT (one where the photocathode is deposited directly on the faceplate)
you'll need to keep the cathode near ground to avoid ions migrating
through the glass and corroding the PC. That means running the anode at
high voltage and coupling the pulses out with a cap or transformer or
something.

Using an air gap between scintillator and tube allows you to keep the
anode near ground, which is much more convenient, but costs you about
half your light. (The collection efficiency goes like the etendue,
which has a factor of n**2 in it.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:

> Mike Monett wrote:
>> "John Miles, KE5FX" <jmiles@gmail.com> wrote:
>>
>>> On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
>>>> My Radiascan Radiacode finally arrived from Russia. After the
>>>> sanctions, I was surprised to see it made it.
>>>
>>> This listing is also very interesting:
>>>
>>> https://www.ebay.com/itm/194659036410
>>>
>>> Basically 2000+ PMT+CsI(Tl) assemblies for sale at around $20 each.
>>> Wonder how they'd compare to the solid-state CsI(Tl) detector assembly
>>> in the Radiacode unit?
>>>
>>> -- john, KE5FX
>>
>> I tried to order one. Does not ship to Canada. Can you order one and
>> mail it to me? I can pay you via Paypal. Thanks.
>
> For any serious use, I'd budget for a replacement PMT. They age out
> after several years, which is probably why these assemblies were
> replaced. They also wear out on account of photocurrent--the usual rule
> is that you can get an integrated anode charge of about 1000 C/cm**2 of
> photocathode area before the gain drops by ~half.
>
> If you're going to use an ionic scintillator in contact with an end-on
> PMT (one where the photocathode is deposited directly on the faceplate)
> you'll need to keep the cathode near ground to avoid ions migrating
> through the glass and corroding the PC. That means running the anode at
> high voltage and coupling the pulses out with a cap or transformer or
> something.
>
> Using an air gap between scintillator and tube allows you to keep the
> anode near ground, which is much more convenient, but costs you about
> half your light. (The collection efficiency goes like the etendue,
> which has a factor of n**2 in it.)
>
> Cheers
>
> Phil Hobbs

Good information. Thanks.

I'm not planning on heavy use. The idea is to compare the scintillator
againt the Radiacode, and try to measure any Radon gas in the basement.
Then it will probably go into storage.

--
MRM

On 28/06/2022 08:01, Mike Monett wrote:
> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:
>
>> Mike Monett wrote:
>>> "John Miles, KE5FX" <jmiles@gmail.com> wrote:
>>>
>>>> On Sunday, June 5, 2022 at 4:07:22 PM UTC-7, Mike Monett wrote:
>>>>> My Radiascan Radiacode finally arrived from Russia. After the
>>>>> sanctions, I was surprised to see it made it.
>>>>
>>>> This listing is also very interesting:
>>>>
>>>> https://www.ebay.com/itm/194659036410
>>>>
>>>> Basically 2000+ PMT+CsI(Tl) assemblies for sale at around $20 each.
>>>> Wonder how they'd compare to the solid-state CsI(Tl) detector assembly
>>>> in the Radiacode unit?
>>>>
>>>> -- john, KE5FX
>>>
>>> I tried to order one. Does not ship to Canada. Can you order one and
>>> mail it to me? I can pay you via Paypal. Thanks.
>>
>> For any serious use, I'd budget for a replacement PMT. They age out
>> after several years, which is probably why these assemblies were
>> replaced. They also wear out on account of photocurrent--the usual rule
>> is that you can get an integrated anode charge of about 1000 C/cm**2 of
>> photocathode area before the gain drops by ~half.
>>
>> If you're going to use an ionic scintillator in contact with an end-on
>> PMT (one where the photocathode is deposited directly on the faceplate)
>> you'll need to keep the cathode near ground to avoid ions migrating
>> through the glass and corroding the PC. That means running the anode at
>> high voltage and coupling the pulses out with a cap or transformer or
>> something.
>>
>> Using an air gap between scintillator and tube allows you to keep the
>> anode near ground, which is much more convenient, but costs you about
>> half your light. (The collection efficiency goes like the etendue,
>> which has a factor of n**2 in it.)
>>
>> Cheers
>>
>> Phil Hobbs
>
> Good information. Thanks.
>
> I'm not planning on heavy use. The idea is to compare the scintillator
> againt the Radiacode, and try to measure any Radon gas in the basement.
> Then it will probably go into storage.
>

If you have radon, try running a CRT television for a few hours and then
wipe down the screen with a damp piece of tissue that has been folded to
about the size of your geiger tube (or its end window if it has one). I
find the dust on my CRT screen is quite radioactive but it has a short
half-life. I'm guessing it is some polonium isotopes. The dust that
collects on the screen doesn't end up in my lungs, so perhaps CRTs are
healthier to have in the house than flatscreens.

On 28/6/22 13:31, Chris Jones wrote:
> If you have radon, try running a CRT television for a few hours and then
> ... The dust that
> collects on the screen doesn't end up in my lungs, so perhaps CRTs are
> healthier to have in the house than flatscreens.

Not as healthy as having no TV. That crap bypasses the lungs and goes
straight to the brain

On a sunny day (Tue, 28 Jun 2022 13:31:26 +1000) it happened Chris Jones
<lugnut808@spam.yahoo.com> wrote in <eCuuK.190184$pqD1.30751@fx01.ams4>:

>If you have radon, try running a CRT television for a few hours and then
>wipe down the screen with a damp piece of tissue that has been folded to
>about the size of your geiger tube (or its end window if it has one). I
>find the dust on my CRT screen is quite radioactive but it has a short
>half-life. I'm guessing it is some polonium isotopes. The dust that
>collects on the screen doesn't end up in my lungs, so perhaps CRTs are
>healthier to have in the house than flatscreens.

Some CRTs from sets that came in for repair had collected tar from smokers.. nicotine.
Wiping clean with alcohol increased brightness considerably :-)
So yes, functioned as air filter ;-)