Progress Update
Re: Progress Update
Good catch, it was a typo. The post is now corrected. However, the ion source was misaligned for both of the two calibration runs. Taking new data now, and WOW! I'll post results soon.
The cathode current is a function of the ion current. It's higher than the ion source current because of secondary electron emission. There is no gas discharge in the main chamber. The camera looking through the viewport just sees a faint blue glow from electrons hitting the glass feedthrough. (And speckles from x-rays of course)
Thanks.
The cathode current is a function of the ion current. It's higher than the ion source current because of secondary electron emission. There is no gas discharge in the main chamber. The camera looking through the viewport just sees a faint blue glow from electrons hitting the glass feedthrough. (And speckles from x-rays of course)
Thanks.
Last edited by Joe Gayo on Mon Dec 21, 2020 4:20 am, edited 1 time in total.
Re: Progress Update
85kV, 180uA, 261k CPM!
Re: Progress Update
90kV, 190uA, 292k CPM!!
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- Posts: 327
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- Real name: Joe Ballantyne
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Re: Progress Update
1.2E+7 n/sec (your last run) is doing VERY well indeed.
What pressure are you running at? If there is no plasma glow at all, I expect you are running at much lower pressures than pretty much everyone else here.
Joe.
What pressure are you running at? If there is no plasma glow at all, I expect you are running at much lower pressures than pretty much everyone else here.
Joe.
- Richard Hull
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- Real name: Richard Hull
Re: Progress Update
Once the voltages get high, the current becomes much less. This is seen in all the mid sixties Farnsworth effort with the cave fusor. Lower pressures 2 microns and just a few hundreds of microamps to 2 ma max. I refer to this as "clean operation". Rarely seen in amateur work. Still, there is always a limit that keeps the fusor either simple or complex from significant return on invested energy.
Joe, Thanks for the tube info. I will have pull my tube out of storage and photograph it. Most BF3 tubes are at 76cm or 1atm with a less than 1atm fill of BF3 and the remainder a backfill of argon.
Richard Hull
Joe, Thanks for the tube info. I will have pull my tube out of storage and photograph it. Most BF3 tubes are at 76cm or 1atm with a less than 1atm fill of BF3 and the remainder a backfill of argon.
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
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
- Mark Rowley
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Re: Progress Update
Joe, I noticed similar results when I operated between 50-67kV. When wall loading was optimal all I needed was 1.5 to 2mA to get some really nice numbers.
67kV was my ceiling. Doubtful I’ll be able to get beyond that anytime soon.
Mark Rowley
67kV was my ceiling. Doubtful I’ll be able to get beyond that anytime soon.
Mark Rowley
Re: Progress Update
The chamber pressure is 1.5E-5 Torr typically during operation.
Just as a interesting side note, the results were seen immediately and no wall loading or "conditioning" was required.
I will be installing my 125kV power supply in the next few weeks. In addition, I have about a factor of 10 in ion current left to increase.
I would like to be the first amateur to reach 1E+8 n/sec.
Just as a interesting side note, the results were seen immediately and no wall loading or "conditioning" was required.
I will be installing my 125kV power supply in the next few weeks. In addition, I have about a factor of 10 in ion current left to increase.
I would like to be the first amateur to reach 1E+8 n/sec.
- Scott Moroch
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- Real name: Scott Moroch
- Location: New Jersey
Re: Progress Update
Joe,
Very nice setup. What type of ion source are you using?
Thanks!
-Scott
Very nice setup. What type of ion source are you using?
Thanks!
-Scott
"In the middle of difficulty lies opportunity"
-Albert Einstein
-Albert Einstein
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- Real name: Jon Rosenstiel
- Location: Southern California
Re: Progress Update
Joe,
Love your setup, and your hv-feedthrough. Guess I'm going to have to go that route too. Keep up the good work.
Love your setup, and your hv-feedthrough. Guess I'm going to have to go that route too. Keep up the good work.
Re: Progress Update
@Scott
The ion source is a simple discharge source that's been cobbled together, nothing special
@Jon
Thanks. Nice work on the Co-60!
The ion source is a simple discharge source that's been cobbled together, nothing special
@Jon
Thanks. Nice work on the Co-60!
Re: Progress Update
Operational tuning (pressure, etc.) has resulted in a dramatic improvement. 100kV, 200uA ion, 2.5 mA cathode, 2 E-5 Torr, 654359 CPM
- Richard Hull
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- Real name: Richard Hull
Re: Progress Update
Great Joe! You are the first to report 100kv results. X-rays gotta' be a killer....Thank goodness the current is low.
I promised an image of my BF3 tube and here it is. the lab was at 33 deg F.
Richard Hull
I promised an image of my BF3 tube and here it is. the lab was at 33 deg F.
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
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