Plasma at Last!

Current images of fusor efforts, components, etc. Try to continuously update from your name, a current photo using edit function. Title post with your name once only. Change image and text as needed. See first posting for details.
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Richard Hull
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Re: Plasma at Last!

Post by Richard Hull » Sun Sep 10, 2017 5:45 pm

8 microns from any roughing pump is fabulous. If from a diff pump, not so good at all.

Your dosimeter pen should read 0 to 200mr or less. The classic yellow civil defense dosimeters read near 300 to 500 roentgens! If one of those puppies moves off zero you should turn your body over so it can brown evenly on both sides as you cook due to radiation. Those old dosimeters let you seek out shelter after a total nuclear exchange where at only 10R chronic dose per day, you can survive much longer in the aftermath before death calls on you. The drawback to a dosimeter is that once it is read, that WAS your total absorbed dose......It is in the bank, so to speak...Too late for a withdrawal.....It is yours to keep as your body begins its natural repair duties....if possible.

If you have a proper low reading dosimeter and read 20mr with it placed right at the fusor viewing window after 2 hours of fusor operation, that is nothing. I have yet to record any reading, other than zero, on a low dosimeter in my pocket as I run a fusor for an hour or more at 40kv. I typically do not take a reading at the view port as I don't press my skull up against the glass for hours on end. I view via a video camera on a monitor as the viewport points down at my conrete floor. Yes, I do have a number of blown pixels in the image detector within the camera after years of x-ray blasts slamming into its silly-con imager.

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.

Robert Dwyer
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Real name: Robert Dwyer
Location: New Mexico

Re: Plasma at Last!

Post by Robert Dwyer » Sat Sep 23, 2017 4:53 am

Added the D2 admission system to the fusor, and replaced a faulty diode, here were the end results:
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In these picture, the pressure was brought down to about 10 microns. Then D2 was admitted, and the pressure raised to 100 microns. After fiddling with the pump's valve, and the gas line's needle valve, I was able to vary the pressure from 10-50 microns of D2. Sadly, These pictures were snagged from a video that was being taken with the fusor camera (a cheap webcam), and I did not have a way to give a definite pressure that corresponds to each picture. I am sure that some of the fusor veterans here would be able to recognize, from the plasma, what the pressure is approximately.

Voltage Measurements? Current Measurements? There are none! That is right. I am using a Fluke 80K-40 to measure the voltage. It measures the AC from the transformer fine (tested up to 20KV AC), but after it is rectified through the diode, after about 9KV as I increase variac voltage, the multimeter shows the voltage decreasing down to about 100v. This is very frustrating, and I do not know what is going on in this regard. As for current, I have yet to build a working circuit. I am hoping this weekend to remedy the voltage/current measurement issues.

What about neutron counts? Well, I just so happened to have the Ludlum 12 turned on at the time, with the He3 tube in the moderator (which is lead shielded), and I saw counts up to about 50,000 CPM (short peak). However, When I removed the moderator, I still got fairly high counts (maybe 10,000 CPM peak). Note: I am not making a fusion claim here, but wanted to show that I may be getting a bit closer to the end goal. Quantitative voltage, current, and pressure data, are an absolute, which I currently lack. Hopefully within the next week I will have all of those.

Anyways, just thought I might share some pretty D2 plasma pictures!
If we throw more money at it, it will have to work... right?

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Richard Hull
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Re: Plasma at Last!

Post by Richard Hull » Sat Sep 23, 2017 9:16 pm

Sounds like you have a neon or oil burner transformer. These are shunted. You need to read my post on neon transformers. It is perfectly normal for a 15,000 volt transformer to read over 15,000 volts and once the plasma begins and the variac is adjusted upward for the voltage to plunge to below 400 volts.

Your high reading on the counter were x-rays or electrical noise and are totally bogus. 0.0 neutrons produced.

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.

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