Updating power supply- worth it?

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Dennis P Brown
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Updating power supply- worth it?

Post by Dennis P Brown »

Currently on the West Coast (San Fran, again for a while - hate flying for nearly 6 hours in a sardine can ... ;) ) but when I get back, I am seriously considering abandoning my 30 kV, 30 ma supply. I just don't feel it is doing the job. I have an 80 kV, (maybe a few milli-amps at best) transformer. Thinking it is worth adding despite the issues of more diodes; however, will need to submerged that trans under oil after pulling a good vacuum on it - have the ability to do all of that but a royal pain.

My pre-amp is driving me crazy with noise at low voltage values on the scope. For this reason, I am also seriously wondering about keeping my turbo since it is the source of said noise. Here, maybe my old oil diffusion pump system is worth re-installing.

If I recall correctly, a scintillation detector (neutron sensitive plastic) does not use a pre-amp so might be worthwhile using that for now - once properly tested. My original electronics box that runs that device appears to be having issues again (power input clapping diode, I suspect.) Neutron detector electronics is just a pain.

I did obtain and install a digital counter in my NIM box recently - while the analog meter is very useful (esp. for general applications) I realize for low count rates that neutron detectors tend to support, not very useful. So the digital counter/display seems to be a necessity rather then just useful.

Assorted issues like these really are problems that get old quick and prove that thinking ahead is far better then my current approch.

In the near time I am determined to try a sphere electrode as a cathode in light of others posts here to see if I can detect any difference in performance.
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Richard Hull
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Re: Updating power supply- worth it?

Post by Richard Hull »

30kv is where fusion starts to get interesting and very obvious to even terrible detection efforts. In general 40+ kv short of 50kv is where the mega mark is found. More volts, much more fusion and many more hassles for those not familiar with really high voltages.

Noise is always a factor in electronics with charge sensitive amplifiers, working around electrical plasmas and other EM radiating gear.

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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Dennis P Brown
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Re: Updating power supply- worth it?

Post by Dennis P Brown »

Thanks, that certainly helps for me by clearing up some points up for me - using the 40 to 50 kV range only is easier and likely to offer higher current performance (and lower x-ray issues!) Also, we worth the effort to get that 80 kV x-former on line, after all (been collecting dust for a while - getting the use of that 30 kV x-former again made me ignore the 80 kV one I bought to replace that unit I gave back; however, the owner decided to let me use it as long as I wanted.)
Matt_Gibson
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Re: Updating power supply- worth it?

Post by Matt_Gibson »

I’d push for the 80kv mark. Things really start picking up once you pass 60kV, heading to 70kV.

-Matt
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Mark Rowley
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Re: Updating power supply- worth it?

Post by Mark Rowley »

Totally agree with Matt. My last PSU iteration could be gently nudged past 80kV which totally revealed a new world of operational parameters. Achieving well past the mega n/s mark with ~1mA (or less) was commonplace with Fusor 2020.

When the day comes to restart my system, 80-100kV will be the goal for the new PSU

Mark Rowley
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Dennis P Brown
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Re: Updating power supply- worth it?

Post by Dennis P Brown »

Good to know, thank you both. That sets the required diodes and cabling.
Matt_Gibson
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Re: Updating power supply- worth it?

Post by Matt_Gibson »

Get after it!

I’m building a new full wave multiplier that I hope to gain 95kV from…Going to need to upgrade all of my connection points as I can hear air breaking down at 70kV.

-Matt
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Dennis P Brown
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Re: Updating power supply- worth it?

Post by Dennis P Brown »

I understand that issue, Matt. So, definitely, I will be placing my diodes under oil
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