Search found 142 matches

by George Dowell
Fri Oct 26, 2012 8:34 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: ISMTR-5 at MURR
Replies: 3
Views: 1701

ISMTR-5 at MURR

<t>This week was the International Symposium of Material Testing Reactors, a.k.a. Research Reactors.<br/> <br/> We have the largest on in the US here at Missouri University Research Reactor , Columbia and the week long meeting was held here this year.<br/> <br/> Now fully converted to LEU fuel, the ...
by George Dowell
Tue Oct 23, 2012 12:33 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: First Homemade APXS-XRF
Replies: 4
Views: 2680

Re: First Homemade APXS-XRF

Less than 10 MICROCURIES,no more is needed or wanted. almost any sealed source will work. One of my favorites is Kr-85, but I expect even Po-210 will work. George Dowell
by George Dowell
Sat Oct 20, 2012 6:23 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: First Homemade APXS-XRF
Replies: 4
Views: 2680

Re: First Homemade APXS-XRF

<t>Photo #1<br/> 1941 US Dime:<br/> 90% Silver<br/> 10% Copper<br/> <br/> Photo #2<br/> 1966 US Dime:<br/> 91.67% Copper<br/> 8.33% Ni<br/> <br/> <br/> <br/> Photo#3 <br/> Comparing the 1941 and 1966 Dimes:<br/> 1941 Dime (YELLOW):<br/> 90% Silver<br/> 10% Copper<br/> <br/> 1966 Dime (GREEN)<br/> 91...
by George Dowell
Sat Oct 20, 2012 4:27 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: First Homemade APXS-XRF
Replies: 4
Views: 2680

Re: First Homemade APXS/XRF

<t>Results.<br/> <br/> <br/> Repeat only the sources shown used to activate XRF.<br/> <br/> Pure elements, 99.99%<br/> Ag, Co, Cu, Fe, Ni, Sn, Ti, <br/> <br/> Gd, Nb, V were machine shop turnings<br/> <br/> In was solder<br/> <br/> La was chemical compound<br/> <br/> Rainbow Hematite was 0.077 gram ...
by George Dowell
Sat Oct 20, 2012 12:48 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: First Homemade APXS-XRF
Replies: 4
Views: 2680

First Homemade APXS-XRF

<t>Just finished a week of testing the first (?) home made APXS/XRF<br/> element analyzer. Pictures to follow.<br/> <br/> So far have analyzed Ti throuh Au.<br/> <br/> Just did a 0.07 g sample of hematite in 6 seconds.<br/> <br/> Thought you might be interested. <br/> <br/> The probe is a sodium iod...
by George Dowell
Wed Aug 29, 2012 10:03 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Ortec 556 Schematic
Replies: 9
Views: 4317

Re: Ortec 556 Schematic

<t>Correct on the wet slug tantalum capacitors self destructing. In the good(?) old days when freeze spray was cheap, we could douse the board 1/4 at a time, turn it on and watch the frost dissapear from defective (heating up) components. <br/> <br/> Nowadays a cheap liquid crystal sheet does about ...
by George Dowell
Wed Aug 29, 2012 1:40 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Ortec 556 Schematic
Replies: 9
Views: 4317

Re: Ortec 556 Schematic

<r>Try<br/> <br/> <URL url="http://www.qsl.net/k/k0ff/GC%20MANUALS/NIM%20Manuals/NIM/ORTEC/556%20HV%20PSU/"><LINK_TEXT text="http://www.qsl.net/k/k0ff/GC%20MANUALS/ ... 0HV%20PSU/">http://www.qsl.net/k/k0ff/GC%20MANUALS/NIM%20Manuals/NIM/ORTEC/556%20HV%20PSU/</LINK_TEXT></URL><br/> <br/> George Dowe...
by George Dowell
Mon Aug 27, 2012 10:08 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: BTI detector
Replies: 8
Views: 3111

Re: BTI detector

My friend sold the BTI to a member. George Dowell
by George Dowell
Tue Aug 07, 2012 1:41 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: 15 kW variac
Replies: 9
Views: 3677

Re: 15 kW variac

As mentioned you won't need a 15 kW Variac, but if you ever do, the practical method is to stack two 28 Amp, 240V Superior Powerstats, and equalize them with a purpose made reactor.

That's what I did in this mid 70's "Big Rig".

Geo
by George Dowell
Thu Jul 26, 2012 11:09 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: The proportional probe as used for low energy photon identification
Replies: 7
Views: 2886

Re: The proportional probe as used for low energy photon identification

Possible source of 8.5 keV:

W (Tungsten) L line is right at 8.4.

The data sheet indicates that the anode is tungsten.

George Dowell