Search found 211 matches

by Jeroen Vriesman
Tue Feb 21, 2017 12:09 pm
Forum: Vacuum Technology (& FAQs)
Topic: Does anyone know this type of seal?
Replies: 5
Views: 2536

Re: Does anyone know this type of seal?

Yes that was the correct answer, question is a few weeks old. Chamber is operational now, but there are still some leaks. Since helium leak detectors are very expensive, I will try with 5%H2-95%N2 and a hydrogen sensor to find the leak. I ordered a TGS821 sensor, which can detect 50ppm H2, but I'm a...
by Jeroen Vriesman
Wed Feb 08, 2017 1:17 pm
Forum: Vacuum Technology (& FAQs)
Topic: What to Make Of Pfeiffer Oil Viscosity?
Replies: 2
Views: 2012

Re: What to Make Of Pfeiffer Oil Viscosity?

Hi. Look at the viscosity for the operating temperature. This will always be "low". Low enough to not influence the pump in any way. I use P3 in my pumps, but I also have a 20L barrel of "Shell S3 RX 100", with a much lower viscosity at 25 deg. C http://www.oqvalue.nl/Images/Products/PDFs/Shell_Vacu...
by Jeroen Vriesman
Wed Jan 11, 2017 10:23 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Power Supply for a Boron based Russian Neutron detector
Replies: 9
Views: 3693

Re: Power Supply for a Boron based Russian Neutron detector

One very cheap and simple way to make a counter tube supply is: a) buy an electric flyswatter (about 4 euro's) b) take out the electronics, and measure the polarity (the wire colours were all wrong...) you now have a 1200V power supply, usually 3V input, in my case the output was floating, but I con...
by Jeroen Vriesman
Sun Dec 25, 2016 3:02 pm
Forum: Other Forms of Fusion - Theory, Construction, Discussion, URLs
Topic: Locheed project
Replies: 6
Views: 4329

Re: Locheed project

David, your text seems to say "there are charges so they produce an opposite magnetic field to the applied field", and then it looks like you are saying this is the same mechanism as in para- or ferro magnetism... I fail to see the "explanation of diamagnetism in a plasma" in that. For as far as I k...
by Jeroen Vriesman
Mon Dec 19, 2016 3:29 pm
Forum: Other Forms of Fusion - Theory, Construction, Discussion, URLs
Topic: Locheed project
Replies: 6
Views: 4329

Re: Locheed project

Interesting!

So they are using the diamagnetic properties of plasma in their confinement...
On that line, does anyone here know why a plasma is diamagnetic?
by Jeroen Vriesman
Tue Nov 15, 2016 3:16 pm
Forum: Vacuum Technology (& FAQs)
Topic: Does anyone know this type of seal?
Replies: 5
Views: 2536

Does anyone know this type of seal?

Have a new vacuum chamber, but two of the seals have an unknown type. And I think I need to replace them. It's all full-metal, and the seal seems to be a long fine circular spring with aluminium. It looks like a re-usable type of wire seal, but I don't know if it's re-usable. The chamber is Leybold ...
by Jeroen Vriesman
Thu Oct 27, 2016 10:00 am
Forum: Vacuum Technology (& FAQs)
Topic: Vacuum System Just Stopped Working
Replies: 3
Views: 1777

Re: Vacuum System Just Stopped Working

If the pressure is constant (at some constant temperature), you might indeed have some vapor from the new oil. What happens when you turn on the diff pump for a few moments (just to heat it a bit), does the pressure rise? Water is usually 1.3mbar at room temperature, so it might be some light hydroc...
by Jeroen Vriesman
Fri Oct 07, 2016 7:38 pm
Forum: Other Forms of Fusion - Theory, Construction, Discussion, URLs
Topic: Forced vibrations in EM-wave? What will happen?
Replies: 10
Views: 4919

Re: Forced vibrations in EM-wave? What will happen?

Sven, a truly free electron cannot interact with a photon in a sense that it would absorb it, or otherwise gain net energy from it. This is because energy and momentum cannot be simultaneously conserved in such an interaction. Compton scattering takes place with the electrons interacting with the ma...
by Jeroen Vriesman
Tue Oct 04, 2016 12:38 pm
Forum: Other Forms of Fusion - Theory, Construction, Discussion, URLs
Topic: Forced vibrations in EM-wave? What will happen?
Replies: 10
Views: 4919

Re: Forced vibrations in EM-wave? What will happen?

Hi, depends on what it is you are asking. "electron at rest", at rest for some observer? If the "EM wave" is seen as a photon there is no interaction if the electron is free (simultaneous conservation of energy and momentum is not possible for an interaction between a photon and a free electron). If...
by Jeroen Vriesman
Sat Sep 24, 2016 7:30 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Problem with oscilliscope
Replies: 11
Views: 6009

Re: Problem with oscilliscope

some time ago I bought one of these Chinese scopes, the type is UTD2052, and it was only 250 euro's new, with two probes. bought it from aliexpress.com, they have newer types now, and usually Chinese specs are exaggerated by at least a factor two. Besides making some noise (fan) and having to figure...