Bubble Detector Malfunction?

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Anze A Ursic
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Bubble Detector Malfunction?

Post by Anze A Ursic »

Hello,

I own a Bubbletech BD-PND Bubble detector that I bought sometime in late April. Since I never got close to fusion at the time it was stored in an office desk inside the original aluminum air tight container. The office is temperature controlled so it did not reach over 30C like the instructions say not to exceed. Today I took it out to see and I noticed several (6 or 7) bubbles in random places. I am currently trying to get rid of them as the instructions say. The office is nowhere near any of the labs, especially not any labs that produce neutrons.

I am curious, what could have caused the bubbles to form? Is it just age or can it be another issue?

Thanks,

Anze
neutron.jpg
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Richard Hull
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Re: Bubble Detector Malfunction?

Post by Richard Hull »

It must be remembered and accepted that 6 months from time of purchase, a bubble detector can 1. fail, 2. begin to fail or 3. be usable for another 3 or 4 months. It is rare to find one that struggles to last a year, be it used daily or never used even once. If those bubbles will not reset by using the instructions, then they must be taken as a permanent back ground and a sign you better get to using it quickly.

I have purchased two at two different times, years ago. One lasted 8 months the later one lasted about 7 months. I already had neutrons for three years prior to buying one of those BTI bubble dosimeters. I started using it the day I received each one of them. I used them to calibrate my 3He tube setup on fusor IV to get an average multiplier reduced from statistical data taken over a few months over many fusion runs.

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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Anze A Ursic
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Re: Bubble Detector Malfunction?

Post by Anze A Ursic »

Richard - thanks, as always. Good thing I'm attempting fusion tomorrow then!

I also contacted Bubbletech and was told that it is a sign of failure due to age... I've reset it several times like the instructions say and the bubbles have seemed to mostly disappear. I just hope once we get neutrons, those bubbles will be much larger.

Anze
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Bob Reite
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Re: Bubble Detector Malfunction?

Post by Bob Reite »

The bubbles in the photo are about the size to expect. If they do not totally go away, subtract those from the total count after neutron exposure.
The more reactive the materials, the more spectacular the failures.
The testing isn't over until the prototype is destroyed.
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Richard Hull
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Re: Bubble Detector Malfunction?

Post by Richard Hull »

Bob is correct...Really large bubbles >2mm are a sign of total failure of the device! Large bubbles will never reset.

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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Anze A Ursic
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Re: Bubble Detector Malfunction?

Post by Anze A Ursic »

I was told by the bubbletech representative that it is still useful, I just have to subtract the 6 current bubbles from the new bubbles post neutron exposure.

Anze
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Richard Hull
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Re: Bubble Detector Malfunction?

Post by Richard Hull »

Due to the normal bubble size. I think we all figured it would be OK in its current state. If you get many bubbles in a run and the the majority do not reset, that is a clue it is near its end of life. Biggeer bubbles and no reset is a clue the end is near or past.

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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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