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"pfjw@aol.com" <pfjw@aol.com>: Oct 22 11:17AM -0700 > did notice that you seem to think that calibration is some- > thing that must be done periodically(every year or two for > example).   No, I stated that the settings, once done, were remarkably stable, even through power-failures. I did have to re-calibrate after a 6-day failure (Hurricane Sandy), but not for failures as long as several hours. > 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. :)   I have not experienced that need - we switched about 2 years ago from a basic DVD player to a compatible, self-upgrading blue-ray DVD with no visible need to re-calibrate - and the software with the kit verified this.     > "That would be my take on the use of that term-of-art for our particular unit. "   > Not sure what you mean by "term of art". > Please elaborate.   Term-of-Art: A word, combination of words or phrase specific to one thing that is used outside of its common definition. To me the term "calibrate" is specific to measuring devices, meters, tube testers, signal generators, rotameters, gauges and so forth that are set to a specific standard such that measurements from them can be trusted. I would not generally consider arbitrary settings based, in part, on taste rather than independent standards, would be any sort of 'calibration'. At least, again, as I understand and would normally use the term. There are those that prefer bright settings and cartoonish colors. De gustibus et coloribus non est disputandum. Quidquid latine dictum sit, altum videtur.   Peter Wieck Melrose Park, PA

thekmanrocks@gmail.com: Oct 22 11:57AM -0700 "me the term "calibrate" is specific to measuring devices, meters, tube testers, signal generators, rotameters, gauges and so forth that are set to a specific standard."   Likewise! DVD test patterns also count, as long as one follows instructions on what to look for when the specific control(brightness, contrast) is adjusted optimally.   I still sense a lot of skepticism in your responses regarding display ALIGNMENT - there, I just found a new name for it that makes sense! :)

whit3rd <whit3rd@gmail.com>: Oct 22 12:14PM -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.   Generally, there's no calibration in an LCD TV that requires touching. Digital signal, not affected by movable magnets or variable resistors. If you use your TV for a computer monitor, though, and have a color printer: you ought to calibrate the video card or the printer driver so that the color prints produce the same colors as the screen display. Getting the correspondence right is important for artistic uses, and requires (1) controlling reflected light off the screen (2) getting as much color gamut and contrast on the screen as on the paper (not easy, might require special paper) (3) controlling the illumination light when viewing printed material (4) adjusting R, G, B zero points (5) adjusting R, G, B brightnesses (6) adjusting for any nonlinearity (usually called 'gamma correction') for R, G, B (7) readjusting from time to time, as papers, inks, phosphors may age.   It can be hard to find and rectify any adjustments. Or, it can be easy - Apple made a ColorSync monitor with internal light sensors that did recalibration in a few seconds if you pressed the front-panel button).

"pfjw@aol.com" <pfjw@aol.com>: Oct 22 12:21PM -0700 > responses regarding display ALIGNMENT - > there, I just found a new name for it that > makes sense! :)   Mpffff..... Here we go again....   Alignment: My primary hobby is vintage radio restoration and repair, so "alignment" is a very specific term. Shifting that term from rF to Visual alignment is not a stretch, just not what leaped to mind when I read your assignment of this term to that process. Telescope people call it "collimation", musicians call it "tuning" but they are all forms of aligning some sort of information for greater accuracy/clarity.   Peter Wieck Melrose Park, PA

stratus46@yahoo.com: Oct 22 03:07PM -0700 > 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?   No. That looked bad because it was in 'store demo' mode. I don't consider the 'user adjustments' namely brightness, contrast, saturation (color), back light and sharpness to fall into the 'calibration' category. Calibration to me involves individual RGB gain, lift and gamma. These were finicky with CRTs but don't need much if any tweaking with LED lit LCD sets.   G²

thekmanrocks@gmail.com: Oct 22 03:09PM -0700 whit3rd wrote: "Generally, there's no calibration in an LCD TV that requires touching. Digital signal, not affected by movable magnets or variable resistors. "   So I will ask you the same question: If you bought and unboxed a brand new flat panel TV for your home, would you leave the user and semi-advanced settings in their factory mode? Have you actually seen a TV(any TV, CRT, Plasma, LED, etc) in its factory defaults?     Again, I'm talking about the SETTINGS, not the broadcast or cable signal fed into the back of it. And no, for the purposes of this dis- cussion, there is no concern of "drift" because we are in the micro- circuit digital realm.

thekmanrocks@gmail.com: Oct 22 06:38PM -0700 Your silence on this subject speaks volumes. Out of the box, a new con- sumer grade TV is like staring at the midday sun for a half-hour to an hour.     It is typically set to "Vivid" or "Dynamic" mode, which is useful only for display in a retail sales floor environment. Contrast, color and sharpness are cranked, color temperature is skewed to 10,000+Kelvin - ultra blue, and every so-called "enhancer" under advanced settings is checked(skin tone enhancer, black level enhancer, digital noise re- duction, etc.) Backlight(if it's a LED or LCD) is all the way up, etc.     Just taking it out of Vivid, and turning off all that CRAP in the advance menu gets you from some vague location in the South Bronx INTO Yankee Stadium, in terms of accuracy! The professional calibration we discussed here will take you from a seat somewhere in the right- field upper deck right onto home plate.     And there are no "personal preferences" when it comes to picture settings - only one right combination of basic and advanced controls, and 1,000 possible WRONG combinations.     it's your choice: Stare at the sun every night during the 6 o'clock news, or see what the host and the world through the cameras really looks like.

isw <isw@witzend.com>: Oct 22 09:14PM -0700 In article <208f2024-220b-42d4-a4f6-8d2decf4bd64@googlegroups.com>, > (1) controlling reflected light off the screen > (2) getting as much color gamut and contrast on the screen as on the paper > (not easy, might require special paper)   I'm pretty sure it's the other way around -- any decent screen will have a much broader gamut than any subtractive color process (i.e. any sort of image printed on paper). Same with contrast ratio -- the screen wins by an order of magnitude or better.   Isaac

Jon Elson <jmelson@wustl.edu>: Oct 22 05:06PM -0500 John Larkin wrote:     >>middle-of-the-road ESR that makes 7800s happy.   > My favorite cheap "MDO" regulator, the LM1117, loves a 10 uF tantalum > on its output. I've had excellent results using two 22uF aluminum electrolytics, one on the input, one on the output, of ZLDO1117 regulators. I've built several hundred devices with that setup, to produce 1.2 to 3.3 V supplies for FPGAs.   Jon

Jon Elson <jmelson@wustl.edu>: Oct 22 05:08PM -0500 rickman wrote:       > Is it about clearing damage or just to show the added resistance > prevented the failure? I found the story a bit hard to follow.   I believe he set up the production line to ramp up the supply voltage with current limiting on EVERY board as it comes out of the reflow oven.   Jon

makolber@yahoo.com: Oct 22 11:15AM -0700 > > 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.   that makes it difficult   I have seen descriptions of replacing the CFL backlights with white LED strips. That would make a nice project.   Mark

"Ian Field" <gangprobing.alien@ntlworld.com>: Oct 22 10:14PM +0100 "Percival P. Cassidy" <Nobody@NotMyISP.net> wrote in message news:d8psurF43noU1@mid.individual.net... > discolored PC board.   > Since the PC board itself showed signs of overheating, I thought it better > to look for a replacement power-supply module   Sadly - heat discoloured PCBs isn't as rare as it ought to be.     The trick is to make a judgment as to whether there is potentially a fire risk. In any case - a replacement from the original source will probably go the same way.   If the problem is on the CCFL inverter board - a company called HR in Spain does pattern spares.   They were originally well known for high quality pattern replacement horizontal output transformers for CRT displays.

"Percival P. Cassidy" <Nobody@NotMyISP.net>: Oct 22 06:05PM -0400 On 10/22/2015 05:14 PM, Ian Field wrote:   > Spain does pattern spares.   > They were originally well known for high quality pattern replacement > horizontal output transformers for CRT displays.   I don't want to put much more money or time into this project: I already have a replacement for our own use but would rather keep it as a spare or donate a working monitor to the thrift store/charity shop (whichever term you use where you live) than simply trash it.   Perce

Jon Elson <jmelson@wustl.edu>: Oct 22 02:38PM -0500 Ian Field wrote:   > hope the heat would desiccate any lingering residues. It seemed OK for a > while, but soon became apparent that the buttons had a life of their own > in humid weather. The Dell monitor I had this problem with had 4 buttons. The power button was fine, the other 3 had trouble at different times. They have a small surface-mount capacitor on the back across each button switch. The switches appeared to be well-sealed, but the soda stuff gut under the caps, ate some of the PC board, and caused lingering conduction. So, I removed all the caps, severely scrubbed the PC board with solvent and a toothbrush, and soldered on, I think, 1000 pF caps where the bad ones were. This has solved the problem.   Your results sound EXACTLY like what mine was doing, and I had to remove the caps, clean and replace with new caps. Most likely, it would work fine without the caps. (I have quite a big stash of SMT parts as I assemble PC boards.)   If the switches are not sealed, then they are almost certainly full of sticky, conductive gunk, and would have to be replaced.   Jon

"Ian Field" <gangprobing.alien@ntlworld.com>: Oct 22 08:44PM +0100 "Jon Elson" <jmelson@wustl.edu> wrote in message news:I6CdnS5l7otOp7TLnZ2dnUU7-audnZ2d@giganews.com... > caps, clean and replace with new caps. Most likely, it would work fine > without the caps. (I have quite a big stash of SMT parts as I assemble PC > boards.)   AFAICR: there were no other components on the front PCB.   Finding the abandoned Dell came in just right, I'm not short of monitors over all - so getting around to working on the faulty one could take a while.

"Ian Field" <gangprobing.alien@ntlworld.com>: Oct 22 05:47PM +0100 <ggherold@gmail.com> wrote in message news:fc686851-ae1f-4f2d-987c-863570a8b631@googlegroups.com... > control.   > (I like the Cockroft chain because it's not all that hard to understand.)   > Any thoughts?     You could probably get away with the chopper transformer out of the SMPSU in a ser top box like a DVB-T type thing.   Using the transformer back to front, you can get pretty decent HT with a simple blocking oscillator on what used to be the secondary.   Or you could go for a capacitor discharge unit. Of course you need another chopper transformer to make the inverter. About 250 - 350V is good enough for the intermediate voltage, you can make a simple relaxation oscillator with 2 or more series neon bulbs and a capacitor to fire the SCR.   Years ago I made a pocket disco strobe along those lines, it used the xenon tube from an old camera and run off 4x AA Ni-Cd cells.

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