60 kV DC Power Supply Questions

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Richard Hull
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Re: 60 kV DC Power Supply Questions

Post by Richard Hull » Sun Jul 09, 2017 7:47 am

Semi-observable fusion!!??

To paraphrase Yoda...

There is no semi-observe
only observe or not observe

Richard Hull
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Fusion is the energy of the future....and it always will be
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ian_krase
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Re: 60 kV DC Power Supply Questions

Post by ian_krase » Sun Jul 09, 2017 1:12 pm

Of course, there is always "observable, but only with much more sophisticated hardware than normal".

I think that the traditional fusor startup sequence isn't really compatible with pulsing but some people do use pulsing.

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Richard Hull
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Re: 60 kV DC Power Supply Questions

Post by Richard Hull » Sun Jul 09, 2017 6:42 pm

A true pulsed fusor would virtually demand a bubble detector or neutron activation for proof of fusion as few could assemble and verify same via electronic neutron detection. Having worked with pulsed systems, the noise around such high current pulsed operations make electronic neutron detections very suspect.

It must be remembered that no one arriving here is an accomplished neutron metrologist! Neutron detection is not something an electonics buff can come and have a quick dabble at and warrant success. Profesionally built and assembled neutron detectors are easily mis-applied by the novice and even by some professional people using them, i.e. positive cold fusion results reported by some of the most prestigious scientists based on mis-applied neutron counter operation.

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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Dennis P Brown
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Re: 60 kV DC Power Supply Questions

Post by Dennis P Brown » Mon Jul 10, 2017 9:06 am

What Richard says is absolutely correct. He has vast experience and one will do well if they listen to his advice (I did.) Other's here can help as well as you are seeing.

While it is correct that any AC system is really (after a diode system is installed - especially a bridge system) is just a "pulsed DC system" one needs to realize that it is an extremely smoothly rising and falling half wave "DC" current - (so noise issues are minimized and manageable (usually but it can still be a problem for marginal detector systems giving false positives ... ) - one gets this drive current by using diodes on an AC system. Building a true pulsed DC system is work and requires a good bit of knowledge so one does not have massive noise on their detector; or if so, as Richard points out - you need a specific detector system to prove fusion.

Fusion in a fusor is both very difficult (fairly involved equipment that must meet some rather specific and difficult parameters as well as detector systems) and extremely easy (why amateurs can do it.) If you want to try something new - feel free to try it - BUT that also means one is trying something no one else has tested and the chance for failure is then high and the bar to prove one has fusion is also raised.

Remember, three areas are always an issue - the power supply; deuterium gas (ultra dry), and one that often creates issues: neutron detection. All three must be successfully overcome for proof of fusion but how this is done is up to you - buy off-the-self (very expensive). Build all these three components oneself; or a mix depending on your knowledge base (most, people use a mix and construct the detector system but buy an appropriate power supply; I built my own power supply after scoring a lucky break on a regular x-former that was negative, and handled both the voltage needed and current (rather over on the current end - which really, as I found, does nothing for increased fusion yield (even a 60 ma at 32 kV gave the same average flux as 25 ma.)

Read the FAQ's and posts by people who have been successful and decide on your approach; whether it works or not, report the results here and you have added to the group knowledge which, regardless of fusion, is useful. Also, I took a number of years and slowly collected and built various items learning via these steps until I built a successful fusor. So, there is nothing wrong with experimenting with systems like a power supply. The error is counting on a new approach and building everything and then trying to overcome all the problems at once - that can be problematic and best to avoid that approach unless interested in the long term. There have been many approaches as one can see if they review the last ten successful fusor's.

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Richard Hull
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Re: 60 kV DC Power Supply Questions

Post by Richard Hull » Mon Jul 10, 2017 9:50 am

I really do not consider any 60hz, half wave or 120hz, full wave fusion as being pulsed fusion, for the reason given by Dennis. Real pusled fusion pulls "amps" of current in a pulse, be it a only a few amps or thousands of amps. Pulsed fusion relies on stored energy being sent in on a sharply rising, high current pulse, depositing the bulk of the stored energy into a short blast of high current plasma. I call this putt-putt boat fusion. Low frequency sine wave, power line based efforts of smoothly rising and falling DC levels is not pulsed fusion.

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.

Joshua Guertler
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Re: 60 kV DC Power Supply Questions

Post by Joshua Guertler » Tue Jul 18, 2017 5:45 pm

So instead of using a pulsed supply of -40 kV DC, should I use a constant supply of -30 kV DC if I am aiming to achieve easily detectable fusion using a neutron bubble dosimeter? The current is a constant 10 mA for both power supply devices.

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Richard Hull
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Re: 60 kV DC Power Supply Questions

Post by Richard Hull » Wed Jul 19, 2017 7:45 am

A pulsed fusor is not the same as a switch mode power supply or a 60hz, powering a fusor! A pulsed fusor is a fusor that relies on huge high current pulses to achieve fusion for only microsecond durations from a large amount of stored energy, normally in a capacitor or a collapsing magnetic field.

A switch mode power supply uses very sort pulses in special magnetic transformers to reach high voltages that are then turned into stable DC voltage at low current to power a fusor continuously.

There are many terminologies that the novice must learn or much confusion can occur.

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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