Ludlum Neutron counter

This area is for discussions involving any fusion related radiation metrology issues. Neutrons are the key signature of fusion, but other radiations are of interest to the amateur fusioneer as well.
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Tom Dressel
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Ludlum Neutron counter

Post by Tom Dressel » Mon Jun 25, 2001 12:52 am

I was going over all the neutron detection related posts on the old forum and came upon Daniele's post reguarding the Ludlum 12-4 neutron detector and counter, built around a BF3 detector.

It runs ~$2.0K, which is very steep! They also have a model 15 detector which detects Alpha, Beta, and Gamma radiation for ~$1.5K. (like Joe Zambelli's counter). Don't get me wrong, I am not ready to roll one of these things out on my Visa card, but especially if the "cheaper" model can do the job of counting neutrons it certainly eliminates a lot of hassles.

I assume that the thing comes with a users manual, warranty, and calibrated.

Short of finding a working Eberline PNC-1 on E-bay for $51.00 (a once per millenium event), what does anyone think of these counters?

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Richard Hull
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Re: Ludlum Neutron counter

Post by Richard Hull » Mon Jun 25, 2001 5:59 am

The rem ball detector is best. I also have an Eberline rem ball unit as well (in a photo on my website's fusion page).

These work just fine, but are indeed pricey.

Do you know for a fact that their alpha-beta-gamma unit will detect neutrons?

Joe Zambelli's unit was a homemade scintilliation unit which used a common plastic scintillator. It would only count gamma, mainly, but also detected proton recoils within the scintillator. His unit as constructed would not detect alpha or beta particles normally encounterd.

I would recommend against there 1.5K$ unit without knowning more about the detection particulars.

As for the scaling, I typically prefer to hook a counter up to the headphone jack and count pulses that way on a digital counter and time the run. This gives a very accurate record of the CPM over a clearly defined period of time. The meter in events or CPM is just a nice visual item to have for instant checks on performance.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.


Re: Ludlum Neutron counter

Post by guest » Wed Jun 27, 2001 5:54 am

Ludlums also have a model 42-30, part# 47-1584 neutron detector. Price is $1425.00. Take a look
I'm still pretty new at this Fusor stuff so I'll leave it to Richard Hull to pass judgement on this item.

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