Wow, that is quite helpfull. Thank you!
Do you have any recommendation for grounding?
I can ground it with a grounding peg somewhere near the lab.
Grounding to the grid is probably very bad idea, am I right?
> Sent: Thursday, February 01, 2018 at 5:45 PM
> From: "nickobert testein" <nickobert.testein@xxxxxxxxx>
> To: arcin_n_sparkin@xxxxxxxxx, "Tesla Coil Mailing List" <tesla@xxxxxxxxxx>
> Subject: Re: [TCML] Tesla Coil and X-ray tube
>
> hey mike, i have this unit, ground one of the leads otherwise nothing much
> will happen.
>
> On Sun, Jan 28, 2018 at 8:20 AM, undisclosed recipient via Tesla <
> tesla@xxxxxxxxxx> wrote:
>
> > There are dozens of Xray transformers listed on craigslist.
> > Most of the units do work or the damage is minimal.
> > I just couldn’t afford to get one since I can’t land a job around here.
> >
> >
> >
> >
> > > On Jan 28, 2018, at 6:33 AM, Michael Loundry <michael.loundry@xxxxxxxx>
> > wrote:
> > >
> > > Hello,
> > >
> > > thank you for the reply.
> > >
> > > No, I have not tried it, but I can try.
> > > I was checking the vacuum tube through the network camera to observe
> > what is happening and I can just tell that brightness of the filament is
> > never changing.
> > >
> > > When any X-rays are present, I should be able to see some dots on the
> > screen. But there is none. So for me this is third confirmation that it is
> > not generating any X-rays.
> > > But again I am convinced that the tubes are OK.
> > >
> > > I have ordered DC power supply that could supply 0 - 100kV and 8mA. I
> > believe that the problem is in the powering.
> > > If this will fail, then we can be certain that the problem is not there.
> > > At the same time it should not generate any strong RF.
> > >
> > > Maybe in 3 days I will know.
> > >
> > > I will let you know.
> > >
> > >> Sent: Sunday, January 28, 2018 at 3:19 AM
> > >> From: Ed <evp@xxxxxxxxxxx>
> > >> To: "Tesla Coil Mailing List" <tesla@xxxxxxxxxx>
> > >> Subject: Re: [TCML] Tesla Coil and X-ray tube
> > >>
> > >> Have you tried measuring current by putting a DC milliameter in series
> > >> with the anode and observing current as you vary filament voltage?
> > >> Meter needs to be bypassed with something like a 1 ufd ceramic capacitor
> > >> for protection.
> > >>
> > >> ED
> > >>
> > >>
> > >> On 1/27/2018 1:18 AM, Michael Loundry wrote:
> > >>> Thank you Dave!
> > >>>
> > >>> I agree in all points with you.
> > >>>
> > >>> I have made also a tests with Flyback 15KV from CRT.
> > >>> DY87 tube was giving approx. 15% more counts than with background.
> > There is just blue glow visible.
> > >>> TRX708 tzbe was not giving anything. No glow visible at all.
> > >>> Some time ago I have made my own vacuum tube that was made of
> > stainless steel tube with a rod in the center. This gave 10x background
> > with the Flyback.
> > >>>
> > >>> All tubes are giving just RF similarly as with a rectifying diodes.
> > Which tells me that it is doing something.
> > >>>
> > >>> I have to admit that all detectors are sensitive to RF to some extent.
> > So it could add counts or even decrease. But it is again in a very small
> > range (5 - 20% change) But still I can see Energy spectrum of all counts.
> > And there is never characteristic X-rays visible.
> > >>> The RF from the Tesla Coil is so strong that all nearby electronics is
> > failing. So it would be good to shield it in some way.
> > >>>
> > >>> I am sure that TRX708 tube has no air inside, since it is behaving all
> > the time as perfect insulator. The Tesla Coil is producing humming as if
> > there is too big gap (no current is flowing) however I connect it. If there
> > is a short or at least some current is flowing the sound is very different.
> > >>> I have tried to measure filament emmisivity and I can measure voltage
> > between Anode and Cathode when only filament is under power.
> > >>>
> > >>> So I am pretty confused because with both HV supplies it looks like
> > there is no electron flow inside with the TRX708, thus no circuit. Both
> > Flyback and Tesla Coil have no current flow between Anode/Cathode. So the
> > vacuum is pretty good I think.
> > >>> On the other hand supplier of the tube tested it with 70KV HV supply
> > and is sure it is perfectly OK. But his DC supply seems to be much better.
> > >>>
> > >>> But why it is giving off RF if no current is flowing? I dont
> > understand it. Probably the current is very, very small.
> > >>>
> > >>> I have to also admit that my Tesla Coil is not able to light up also
> > any light bulb. There is just arc through the entire bulb or there is
> > nothing (depending on configured voltage). No glow at all. This is reason
> > why I think there is something wrong. Ends from the secondary are so that
> > one is touching filament and second end is at the top of the bulb.
> > >>> My tesla coil is not grounded and that is probably reason since I know
> > that with other Tesla Coils I have saw it arcs everywhere inside the bulb
> > just by touching one end. But probably everybody is grounding the coil
> > which is what I dont wish to do.
> > >>>
> > >>> I have full schematic of my Tesla Coil so you can look at this:
> > >>> https://ibb.co/gWyZgw
> > >>>
> > >>> By the way it is fully shielded with 3+ mm of Pb so that nothing can
> > escape. Also time that it is running is just few miliseconds.
> > >>>
> > >>> Does it make any sense for you?
> > >>>
> > >>>
> > >>>> Sent: Friday, January 26, 2018 at 11:54 PM
> > >>>> From: "David Speck" <Dave@xxxxxxxxxxxxxxxx>
> > >>>> To: "Tesla Coil Mailing List" <tesla@xxxxxxxxxx>
> > >>>> Subject: Re: [TCML] Tesla Coil and X-ray tube
> > >>>>
> > >>>> Michael,
> > >>>>
> > >>>> According to this table:
> > >>>>
> > >>>> http://www.sciencemadness.org/talk/files.php?pid=400982&aid=38982
> > >>>>
> > >>>> your 9 cm arc between sharp electrodes should be indicating about 70
> > kV,
> > >>>> which should be enough to make X-rays.
> > >>>>
> > >>>> Even without external rectifiers, an X-ray tube is capable of
> > operating
> > >>>> in self-rectifying mode on an unrectified AC source. It would
> > produce a
> > >>>> lot of unwanted, scattered radiation on the reversed biased part of
> > the
> > >>>> cycle, but it should still produce plenty of X-rays when forward
> > biased.
> > >>>>
> > >>>> Have you checked for X-ray output with a foolproof X-ray detector like
> > >>>> an X-ray sensitive phosphor sheet from a medical X-ray cassette? Have
> > >>>> you been able to see any faint green fluorescence of the tube walls
> > >>>> during operation?
> > >>>>
> > >>>> How can you be certain that your X-ray detectors are working properly?
> > >>>>
> > >>>> From what I've read on the Geiger Counter Enthusiasts Usenet groups,
> > >>>> ionization chamber radiation detectors are the preferred devices for
> > >>>> detecting and measuring X-rays in the energy range that you indicated.
> > >>>>
> > >>>> In the circumstances you describe, I would speculate that either your
> > >>>> tubes are up to air, and not producing X-rays, or that your detectors
> > >>>> are not working.
> > >>>>
> > >>>> See if you can find a sympathetic dentist to direct his X-ray machine
> > at
> > >>>> your detectors to be sure that they are actually working. Typical
> > >>>> dental X-ray machines run in the 88 - 100 KV range.
> > >>>>
> > >>>> Be careful. 70 KV X-rays will produce a substantial skin dose while
> > >>>> being imperceptible.
> > >>>>
> > >>>> Dave
> > >>>>
> > >>>>
> > >>>> On 1/26/2018 8:20 AM, Michael Loundry wrote:
> > >>>>> Dear subscribers,
> > >>>>>
> > >>>>> I have recently bought Tesla Coil with adjustable output voltage 5 -
> > 100kV.
> > >>>>> It is driven by thyristor (SCR) circuit and powered from the mains.
> > >>>>> Tesla coil itself is in mineral oil. Secondary has both ends
> > available from the plastic case, so there is no grounding.
> > >>>>> It is this unit: http://i.ebayimg.com/images/i/
> > 311006967911-0-1/s-l1000.jpg
> > >>>>> The Tesla Coil seems to be powerfull enough - can produce a lot of
> > ozone, arcs can be at least 90mm long.
> > >>>>> Input power is around 200W.
> > >>>>>
> > >>>>> I would like to ask you, if you think that with this Tesla Coil I
> > should be able to produce X-rays?
> > >>>>>
> > >>>>> What I have?
> > >>>>> - Proper lead shielding
> > >>>>> - NaI 2.5x2.5" scintillator probe with sensitivity for 15keV - 3MeV
> > >>>>> - Additional Geiger Counter with sensitivity from 50keV - 3MeV
> > >>>>> - X-ray tube Trophy/Kodak TRX708
> > >>>>> - Vacuum tube DY87
> > >>>>> - 20x rectifier diode for 18KV, 20mA (can be connected in a series)
> > >>>>>
> > >>>>> My goal is to produce X-rays, but unfortunately I am not able to do
> > so in any case.
> > >>>>> Both X-ray tube and vacuum tube are basically new and verified to
> > work.
> > >>>>>
> > >>>>> What I have tried:
> > >>>>> 1. Heating filament with AC/DC to nominal current/voltage for
> > maximum electron emmisivity.
> > >>>>> 2. Connecting TC to Anode and Cathode.
> > >>>>> 3. Changing TC polarity on the panel (this is swapping live/neutral
> > for the primary side).
> > >>>>> 4. Using rectifying diodes so that output is pulsed DC.
> > >>>>> 5. Swapping Anode and Kathode wires.
> > >>>>> 6. Tried to change filament voltage from 0 to max allowed.
> > >>>>> 7. Tried same procedures with DY87.
> > >>>>> 8. Tried it with arcing (wire for cathode had a small gap to create
> > arcs).
> > >>>>>
> > >>>>> Of course collimator from the X-ray tube is positioned parallely to
> > radiation detectors.
> > >>>>>
> > >>>>> What I was able to produce was just RF in some cases.
> > >>>>>
> > >>>>> Could you please let me know what could be wrong? Why my Tesla Coil
> > is not producing any X-rays? Is some grounding required?
> > >>>>> I know my meters can pick X-rays pretty well.
> > >>>>>
> > >>>>> Thank you!
> > >>>>> _______________________________________________
> > >>>>> Tesla mailing list
> > >>>>> Tesla@xxxxxxxxxxxxxxxxxx
> > >>>>> https://www.pupman.com/mailman/listinfo/tesla
> > >>>>>
> > >>>> _______________________________________________
> > >>>> Tesla mailing list
> > >>>> Tesla@xxxxxxxxxxxxxxxxxx
> > >>>> https://www.pupman.com/mailman/listinfo/tesla
> > >>>>
> > >>> _______________________________________________
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> > >>> Tesla@xxxxxxxxxxxxxxxxxx
> > >>> https://www.pupman.com/mailman/listinfo/tesla
> > >>
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> > >>
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