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ggherold@gmail.com: Oct 22 06:50AM -0700 > HV, not to worry, I've been bitten several times, > and have a healthy respect.   > George H.   OK I hooked this up to the spark of my tractor last night. The nice cherry glow of Neon was visible.   Thanks everyone for the suggestions, comments and links.   So here's a question, My daughter likes the elements, we have a small collection. Adding Neon would be nice, but we'd have to make a little circuit to power the tube.   1.) How much voltage do I need to start it? (10kV?) 2.) could I run it CW or would a pulsed thing be better/ easier. 3.) How to make the HV? My first thought was a cockroft-walton chain. Could I choose the caps and frequency such as to have a crude current control.   (I like the Cockroft chain because it's not all that hard to understand.)   Any thoughts?   George H.

jurb6006@gmail.com: Oct 21 12:59PM -0700 Well that's all fine and good, but why did you use the form of a question in the title ?   Anyway, there is a disk out there called "Video Essentials" which is supposedly a great aid in doing that. However, for an accurate greyscale you need something to which to compare. For video cameras they had what were called lightboxes which supposedly had a specific color temperature. With a monitor, maybe you can compare to a high brightness piece of paper lit by a lamp with a specific color temperature. Or perhaps sunlight.   Though things can run off still, it is nowhere near as bad as CRTs were. If they weren't burned in enough after cathode activation they would drift, and later those miniature cathodes got hotter with increased beam current and drifted, necessitating AKB. (Auto Kine Balance) And then there is convergence and purity. The Earth's magnetic field affected the purity quite a bit, and convergence to a lesser degree, except on projection TVs.   The LCD TVs do not really have these problems, they are going to inherently be more accurate out of the box. Same with plasmas but the phosphors in a plasma can weaken with age like any other phosphor. Someone told me the gas in them wears out, and that reduces color temperature. I do not believe it, that should affect all colors equally. I think the blue phosphor wears out first. Blue phosphors are the least efficient and therefore will get more drive.   While there are no cathodes, the phosphor does still burn in and weaken with heavy use.   There is no convergence or purity adjustment on plasma or LCD (which includes what they call LED now). Greyscale and color demodulation, are all there is, and with other than NTSC (composite or SVHS) there is no color demodulation either.

thekmanrocks@gmail.com: Oct 21 04:32PM -0700 jurb...@gmail.com wrote: "Well that's all fine and good, but why did you use the form of a question in the title?"     Because it seems in the last 10 years calibration, or at least the very concept of it, is becoming marginalized, less relevant. The occurrence of the word "calibration" has dropped significantly since the early 2000s according to searches I conducted in usenet groups related to video technology and production.     I sincerely want to share my calibration experiences with others because I'm so excited by what it has done for my TV and video viewing experience. My problem is adjusting my "elevator speech" so that the common man(woman) 'get' what calibration does for their equipment and their viewing.

stratus46@yahoo.com: Oct 21 09:37PM -0700 I've worked in broadcast and post production since 1976 and calibrated many monitors, some used for THX film transfers and verified by their tech. Calibration was mandatory with CRT monitors and on a regular basis. The new TVs are amazingly consistent and I find no desire and certainly no need to 'tweak' them. In fact, unless you're very qualified I would not allow you to touch my TV.   G²

thekmanrocks@gmail.com: Oct 22 01:24AM -0700 stra...@yahoo.com wrote: " The new TVs are amazingly consistent and I find no desire and certainly no need to 'tweak' them. In fact, unless you're very qualified I would not allow you to touch my TV.   G² "   So if I understand you correctly, If you were to buy a brand new flat panel set, connect it all up and start watching it, you would leave the user menu settings all in their factory positions?

"pfjw@aol.com" <pfjw@aol.com>: Oct 22 05:19AM -0700 > has fallen out of favor!   > Waiting for the crickets ....   > thekmanrocks@gmail.com - Switch accounts - Desktop   That would depend. We have a Panasonic Plasma TV - the factory settings are *very* bright and the color mix verges on the cartoonish. "Calibrating" in that case allows the user to set the color range, average brightness and similar parameters to a more reasonable setting. One can purchase a 'kit' to help with this, and/or use other means to get the colors true. Once done, as otherwise noted, the system seems to remain remarkably stable, even through power-failures.   That would be my take on the use of that term-of-art for our particular unit.   Peter Wieck Melrose Park, PA

thekmanrocks@gmail.com: Oct 22 06:29AM -0700 pf...@aol.com wrote: "- show quoted text - > thekma...@gmail.com - Switch accounts - Desktop   That would depend. We have a Panasonic Plasma TV - the factory settings are *very* bright and the color mix verges on the cartoonish. "   So you have observed, and agree, that factory default settings on consumer TVs such as your Panasonic and on my Samsung LED are not ideal for extended viewing.       "Calibrating" in that case allows the user to set the color range, average brightness and similar parameters to a more reasonable setting. One can purchase a 'kit' to help with this, and/or use other means to get the colors true. Once done, as otherwise noted, the system seems to remain remarkably stable, even through power-failures. "   And you agree with calibration in your particular case. I did notice that you seem to think that calibration is some- thing that must be done periodically(every year or two for example).   That may have applied in the case of CRT-based TVs or projectors, yes. But not with modern digital flat technology - UNLESS - you change one of your input sources, or upgrade, I.E. from a standard DVD to a Blu-Ray deck. You then recalibrate that input for that device. I tell all of my customers this: that their calibrated settings should not drift for at least a decade. :)       "That would be my take on the use of that term-of-art for our particular unit. "   Peter Wieck Melrose Park, PA "   Not sure what you mean by "term of art". Please elaborate.

mike <ham789@netzero.net>: Oct 21 11:19AM -0700 On 10/21/2015 9:31 AM, Percival P. Cassidy wrote: > sending money to a person or business of unknown integrity.   > Where do I go from here?   > Perce There's typically a sensor that shuts down the backlight if it senses a problem with the backlight. I fixed one of those with a new transformer, but the first one of those shipped to me with an open secondary. Second one worked.   I "fixed" a second monitor by disabling the protection chip. I wouldn't recommend that to anyone else tho...   If the backlight is on a different board, you may find something there. It's possible that the new board had the same failure mode.   Normally, you'd expect the image to stay up even if the backlight turns off, but who knows what the designer decided on that model.   Had one monitor that had a bad cap in the 5V. Supply. The spikes on the 5V caused the controller chip to malfunction and lock up.   Probe around with a digital storage scope to see what happens on power up.

"Percival P. Cassidy" <Nobody@NotMyISP.net>: Oct 22 09:09AM -0400 On 10/21/2015 02:19 PM, mike wrote:   > and lock up.   > Probe around with a digital storage scope to see what happens > on power up.   I neither own nor have access to any kind of scope.   The power module has connectors for four 2-wire leads that run to one vertical edge of the screen, and another connector from which a multi-conductor lead (more than 2 conductors, but I don't recall how many, and it's not open at the moment for me to look) going to the bottom edge of the screen (perhaps to the control buttons?). There is another module that has the analog and digital signal connectors, a multi-connector lead from the power module, and a shielded multi-connector lead going to the top edge of the screen.   Perce

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Oct 22 06:56AM -0500 "NewsDemon" <mark_zacharias@sbcglobal.net> wrote in message news:4xJVx.91206$Bl2.83615@fx27.iad... > connector, > etc.   > Mark Z.   Sorry for multiple postings. Problem with new server.   mz

"pfjw@aol.com" <pfjw@aol.com>: Oct 22 05:28AM -0700 On Monday, October 12, 2015 at 6:00:31 AM UTC-4, Nick de Smith wrote:   > When its fine (90% of the time) it's an excellend radio cassette...   > Bit puzzled as to where to go next...   > Thanks   First, the disclaimer: I am not familiar with that unit.   Now the two alternate diagnoses: a) If a capacitance-start (solid-state contact-start switch), replace the capacitors as already noted. It might not be a bad idea in any case. And don't stop with the main filters, look to any caps in the starting circuit. Such switches may also operate a small reed relay or solid-state relay. If a reed relay, it may be worn out and not holding. If an SS relay, see caps, above and elsewhere.   b) If a mechanical switch, look for dirty contacts, a slipped or worn-through contact or similar. Can you jumper the switch and have it operate normally?   As I remember, and, for the record, that little pacific-rim audio equipment that I own is all Sony or Yamaha, Sony does like solid-state switches as they are much easier to manage with remote control, so I expect that this will devolve to a capacitor problem.   Best of luck with it.   Peter Wieck Melrose Park, PA

911rsrman@gmail.com: Oct 21 01:52PM -0700 On Wednesday, March 3, 2010 at 9:13:31 PM UTC-8, Sparks Fergusson wrote: > handle the load like it did before.   > Anyone have any ideas?   > Thanks!   Just replaced a "run capacitor on my 5 H.P. Champion compressor that was having a similar issue...All is well now.

"pfjw@aol.com" <pfjw@aol.com>: Oct 22 05:12AM -0700 > Just replaced a "run capacitor on my 5 H.P. Champion compressor that was having a similar issue...All is well now.   Yes!   This will very most likely be the problem. The motor is an AC induction motor, no brushes. But the run capacitor is critical to proper torque. And, if you are already in there and the happens to be a start-cap, do that one too.   Peter Wieck Melrose Park, PA

etpm@whidbey.com: Oct 21 11:03AM -0700 WHOOPS! I meant to post this on rec.crafts.metalworking. If anybody here is interested I'll post updates here too. Eric

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