Fusor Forums

Richard,

I was not doubting the neutron numbers, merely questioning the measurement taken by Tim with the rem ball, as it seemed to be reading a mere 25%.

Steven

I took the measurement using Tim's ball. I can assure you that the meter read 9 mrem. I expect that the meter is probably set for thermal neutrons, but I would have to ask Tim. The QF for 2.45 Mev would tend to raise the real reading, but I would have to check the tables to see how much.

I looked back at HEAS 2011 data and Richard posted that Tim measured 7.7 mrem using the same ball at 1.1 million neutrons per second. So, the numbers appear to correlate.

Jim, thanks for the cross check on the old figures. There must be some issue with the rem ball or distance involved. I remember that while you were taking the reading you were having to avoid the naked 43 kilovolt top electrode and this allowed you to not get but so close.

Richard Hull

I had a wonderful time as usual, and came home with a couple "spicy" goodies as well as a nice little x-ray machine, an electrometer, and a Russian night-vision scope that emits x-rays. Thanks to Richard for his hospitality!

Looking at the 9 mrem / hr measurement (which I wasn't present to observe), if it were made with a standard 9" remball placed directly against the fusor chamber, it should read about 29.5 mrem / hr at 1.4M n/s. It's impossible to say if the discrepancy is the remball (which it easily could be, for instance if a different cable is being used on it than the one it was cal'd with), or some noise on Richard's big detector, etc. And as Jim points out, it may not be accurate to assume that the center of the remball was 4.5" from the fusor flange as there is a lot of steric hindrance due to the vacuum gauges, feedthrough, and so forth. Suffice it to say, this was not a precision measurement.

Looking forward to next year!
-Carl

Yes, thanks for the numbers. By having so many people measure the same source, and come to consensus about the readings, we've managed to get a pretty decent calibration across labs, which can only be for the good of all. It's helped me a great deal, even though I didn't make it this time.

Here are some more photos supplied by Tom Klynes. Thanks to Tom for sending these along.

Most relate to photos already posted. Cloud chamber watchers, etc. However, we see Q in the third image with his homemade florence flask-on ring stand coffee mug with Warren Ellingsen beside him discussing something of great import. Q is famous for his interesting bring-alongs.

The last image is one rarely taken and a first for HEAS imagery. It's the junk food pile which sustains so many DIYs and amateur science dweebs in their daily lives and during critical periods of experiment. The C12H22O11 based products like cake, donuts cookies and the like have already been consumed by the masses with the gusto of a hound dog. (aid to cerebration) Only the NaCl based piles remain. (electrolyte replacement)

Fresh goodies were brought in throughout the day, but didn't last long.

Richard Hull

More pix from Cameron Prince at...

https://teslauniverse.com/build/galleri ... conference

Richard Hull