11.7 dB attenuation

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Daryl
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11.7 dB attenuation

Post by Daryl » 23 Sep 2016, 11:00

Received 75 lbs of Lead in 18 bars from eBay user industrialsupplylv for building a castle.
I just had to throw them together before melting any.
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Daryl Duckworth / Sun City, Arizona / Amateur Radio NN0W / High Energy Toys: Radex One, GQ GMC-320 Plus / Ludlum 14C with 44-9 Pancake / GS-1100A / Irad 2x2.25 Bicron BC-412 / Scionix 2.25 x1.5 NaI(Tl)

Daryl
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Re: 11.7 dB attenuation

Post by Daryl » 23 Sep 2016, 11:02

Using the Ludlum 3 with an Alpha Spectra I measure a background of 6000.
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Daryl Duckworth / Sun City, Arizona / Amateur Radio NN0W / High Energy Toys: Radex One, GQ GMC-320 Plus / Ludlum 14C with 44-9 Pancake / GS-1100A / Irad 2x2.25 Bicron BC-412 / Scionix 2.25 x1.5 NaI(Tl)

Daryl
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Re: 11.7 dB attenuation

Post by Daryl » 23 Sep 2016, 11:04

Then I put the Alpha Spectra probe into the cave and measured 400.

Doesn't 15x reduction = 11.7dB ?

Next: Move the computer into the new "laboratory" and hook up the Spectacular.

I saw on YouTube how silicone works well for molding lead in the one ounce sizes.

I was thinking on how to make a mold to pour lead so as it would be a hollow cylinder made for a probe (like a bundt cake pan).
Thick paper mache lined with silicone?
Old coffee can with a center dowel rod?
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Daryl Duckworth / Sun City, Arizona / Amateur Radio NN0W / High Energy Toys: Radex One, GQ GMC-320 Plus / Ludlum 14C with 44-9 Pancake / GS-1100A / Irad 2x2.25 Bicron BC-412 / Scionix 2.25 x1.5 NaI(Tl)

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Steven Sesselmann
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Re: 11.7 dB attenuation

Post by Steven Sesselmann » 23 Sep 2016, 12:48

Daryl,

I am not familiar with background measurements in dB so I can't comment.

On casting lead you can use anything as a mould as long as it doesn't burn or melt under the heat. Make sure you work in a well ventilated area preferably outdoors and use safety glasses and leather gloves.

You could use a copper pipe as a lining for your lead castle, this would help attenuate the Pb x-rays.

Steven
Steven Sesselmann | Sydney | Australia | gammaspectacular.com | groundpotential.org | beejewel.com.au |

Daryl
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Re: 11.7 dB attenuation

Post by Daryl » 23 Sep 2016, 18:40

Steven,

Sorry, that dB stuff is from radio. Relative power based on base 10 log. You see the 511 KeV annihilation energy is the equivalent of a radio signal at 123.37 Pentahertz or a wavelength of 2.43 nanometers. My bad.

Thank you for the suggestion on the copper pipe. . I went looking all over the net for copper pipes. Yikes! Ouch!

Well I ordered an 3 inch diameter 8 inch long type M from Moonshine-still.co. Under $50. !! You can order it by the inch for your personally designed still! Pay attention moonshiners!

Now, what do I do about a Cadmium layer on the outside of that copper pipe?
Last edited by Daryl on 24 Sep 2016, 04:08, edited 1 time in total.
Daryl Duckworth / Sun City, Arizona / Amateur Radio NN0W / High Energy Toys: Radex One, GQ GMC-320 Plus / Ludlum 14C with 44-9 Pancake / GS-1100A / Irad 2x2.25 Bicron BC-412 / Scionix 2.25 x1.5 NaI(Tl)

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MartinM
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Re: 11.7 dB attenuation

Post by MartinM » 23 Sep 2016, 18:56

Daryl wrote: Now, what do I do about a Cadmium layer on the outside of that copper pipe?
Not the best idea to work with Cd, it's quite toxic. Why not use tin? Albion Alloys offers tin sheets.
Martin Malik, http://www.hwinfo.com

Daryl
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Re: 11.7 dB attenuation

Post by Daryl » 24 Sep 2016, 10:12

I'm thinking tin also has a much lower melting point and could be poured between the copper pipe and its thick lead sleeve.
Daryl Duckworth / Sun City, Arizona / Amateur Radio NN0W / High Energy Toys: Radex One, GQ GMC-320 Plus / Ludlum 14C with 44-9 Pancake / GS-1100A / Irad 2x2.25 Bicron BC-412 / Scionix 2.25 x1.5 NaI(Tl)

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