On 2/18/2012 10:33 AM, Lucky wrote:
Hey Grahame thanks for those links especially the GE manual, just what I need to brush up on my theory.As a point of (possible) discussion there is one thing I totally disliked. Upon first linking to the site 'Scribd' I/we are greeted with a message: "You Must be Logged in to Download a Document...Login with Facebook". Okay thinks I, logging in with Facebook AND giving away all my details, allowing Scribd access to my profile , my friends profiles, allowing Scribd to post on my wall...allowing Scribd access to my wife, to sacrifice my first born etc only to be confronted with a message when attempting to download....nope you can't have this unless you pay us money! Okay you only need pay a small sum for one days access or month/yearly or upload something (How much? For 'upload credits'?) It is still con trick afaiak, if you have to pay a fee then they should say so upfront NOT after I have given away MY details and all the permissions for facebook etc (which is worth money in its self but I did not charge for!). Let's face it we're already the 'product' not the consumer being on facebook to start with but I am against any site that is not upfront with any fees that may need paying and especially when greeted with such an opening message! I now have to delve into FB to delete those permissions given. As an aside there are of course 'ways and means' around it like a greasemonkey script or youtube for instance more than likely posted by people also peeved into sharing their details with nothing in return. Had I been informed from the start that a small fee is payable I would have gladly paid for such an informative (electronic pdf copy of) book. Anyone have any thoughts on this or the like? On 18 Feb, 12:04, Grahame Marsh<[email protected]> wrote:I just posted a link to Acton& Swift Neale is here (download a pdf and read online) :http://www.archive.org/details/ColdCathodeTubeCircuitDesign Glowlamp manual is here:http://www.scribd.com/doc/34672942/General-Electric-Glow-Lamp-Manual-... Any more links folks? On the yahoo site we had a book/magazine section - how can that best be arranged with google? Grahame On 18/02/2012 11:47, Dekatron42 wrote:Michel, have you read the books: Cold Cathode Discharge Tubes by Acton& Swift Cold Cathode Tube Circuit Design by D M Neale Glimmr hren und Kaltkatoden-Relaisr hren by Otto Paul Herrnkind Glowlamp Manual by General Electric Kaltkatodenrelaisr hren Dekadenz hlr hren by DR Roland H bner Kaltkatodenr hren by Greiff Electronic Counting Circuits Techniques& Devices by MULLARD Ziffernanzieger hren by VALVO There is a lot about what happens inside a cold cathode tube in those books with explanations about charge, deionization and stuff - way above my head but it gave me a good ground to stand on when trying to understand more about what happens inside these tubes, and it was enough for me to understand it at a basic level. There are of course many more books that describe these phenomena, but those are the ones that I have borrowed from libraries and looked into. /Martin On 18 Feb, 11:56, Cobra007<[email protected]> wrote:I think you're right and that would explain why I can't really measure the capacitive component. You're talking about negative resistance, I had not looked at it that way but it sounds very reasonable, the voltage over the tube will decay while the resistance increases so that would indeed be negative. I do indeed use a pulse with series resistor, I let the voltage drop from say 150V down to say 100V to turn the tube off. Normally, with a capacitive load, the tube's cathode would then immediately drop to -50V. This doesn't happen, it doesn't even go below 0V most likely because the negative resistance wins over the capacitive properties. I think the inductive component is very small. At some frequency it should resonate I would assume but I can't see that in my step response so the inductance must be very very small. Michel On Feb 18, 1:51 am, John Rehwinkel<[email protected]> wrote:How does a nixie behave in the first few hundred micro seconds after switching off. Is it resistive, capacitive or inductive? I would assume it to be capacitive but that is not exactly what I measure.That's a really good question, and I'll admit I haven't attempted to measure it. So, in the grand tradition, I'll take a guess at it. Said guess is that the plasma stays ionized for a bit before the atoms settle back down to ground state, so it would have the electrical properties of an ionized plasma, which would be: negative resistance. This would decay to capacitance as the gas became nonconductive. there's of course inductance from the leads, and the capacitance and inductance are distributed (especially in larger nixies), making a sort of sloppy transmission line with varying characteristics. Now I want to see if various nixies have resonant frequencies, and what I'd get back if I hooked a TDR to a really big one.It seems more resistive, so I am wondering if this is normal or am I doing something wrong?I'm curious as to how you're measuring this in the first place. Are you using pulses with a trailing voltage and a series resistance, or what? - John- D lj citerad text -- Visa citerad text -
-- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
<<attachment: IRACOSALES.vcf>>
