Search found 430 matches

by ian_krase
Thu Jun 14, 2018 3:50 am
Forum: New User Chat Area
Topic: Diffusion pump power wire convert
Replies: 7
Views: 405

Re: Diffusion pump power wire convert

To slightly elaborate on "makes life easier for switches":

Since AC is going around zero volts and zero amps 50-60 times a second, it's much easier to stop an arc.
by ian_krase
Thu Jun 14, 2018 3:47 am
Forum: New User Chat Area
Topic: HV rated feedthroughs
Replies: 5
Views: 445

Re: HV rated feedthroughs

Is my impression that Paschen's Law keeps that from happening for a while compared to the air side correct?
by ian_krase
Thu Jun 14, 2018 3:17 am
Forum: The Trading Post
Topic: [FREE] Nonfunctional MKS 919 Guts
Replies: 0
Views: 286

[FREE] Nonfunctional MKS 919 Guts

I have the guts of an MKS 919 hot cathode ionization gauge controller for free to anybody who takes it off my hands. These guts are supposedly nonfunctional, and definitely contain at least one bodge wire, but they also have a variety of interesting and not-so-interesting parts. Notably, two large a...
by ian_krase
Mon Jun 11, 2018 7:11 pm
Forum: New User Chat Area
Topic: HV rated feedthroughs
Replies: 5
Views: 445

Re: HV rated feedthroughs

Totally untrue.

What is true is that many feedthroughs can be upgraded by adding more insulation / oil immersion on the atmosphere side. So you might easily make a 20 kV feedthrough good for 50 or more kV.
by ian_krase
Mon Jun 11, 2018 7:10 pm
Forum: Fusor and/or General Fusion Theory (& FAQs)
Topic: Does this look sufficient for a proof of concept fusor?
Replies: 7
Views: 1043

Re: Does this look sufficient for a proof of concept fusor?

That Bell jar looks pretty thin edged. Doesn't that style of Bell jar normally have a think heel if meant for vacuum?
by ian_krase
Sat Jun 09, 2018 7:33 am
Forum: Books & References
Topic: Two Vacuum Engineering Titles
Replies: 2
Views: 332

Re: Two Vacuum Engineering Titles

Huh, written by the very Mr. Pirani himself.
by ian_krase
Mon Jun 04, 2018 8:10 am
Forum: Vacuum Technology (& FAQs)
Topic: Foreline pump base pressure degraded
Replies: 10
Views: 1042

Re: Foreline pump base pressure degraded

Oh boy. I've been letting my whole system up to atmosphere this whole time.

New oil it is.
by ian_krase
Sun Jun 03, 2018 5:33 am
Forum: Vacuum Technology (& FAQs)
Topic: Foreline pump base pressure degraded
Replies: 10
Views: 1042

Re: Foreline pump base pressure degraded

I tried blankoff and gas ballast for a while but the only result was a bit of foaminess in the oil. Going to try changing the oil when I have a chance.
by ian_krase
Tue May 22, 2018 11:43 pm
Forum: Vacuum Technology (& FAQs)
Topic: Foreline pump base pressure degraded
Replies: 10
Views: 1042

Re: Foreline pump base pressure degraded

I tested with nothing but a valve between the pump and the gauge, should go with nothing but the gauge. 8 microns was measured over a year ago, with the pump on a system reaching sub-30-microns routinely for months later. However, I haven't measured the pump's ultimate vacuum in some months since th...
by ian_krase
Tue May 22, 2018 11:42 pm
Forum: New User Chat Area
Topic: Usable transformer
Replies: 13
Views: 767

Re: Usable transformer

1. Add a resistive ballast. You should be doing this anyway, but it's particularly important for a less than stable power supply. 2. Make your fusion reactor a more stable design -- this usually means either adding ion guns (complicated and expensive) or moving to a completely different design such ...