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tabbypurr@gmail.com: Jan 05 08:56AM -0800 On Friday, 5 January 2018 16:31:22 UTC, Terry Schwartz wrote: > Ok, a quick google search reveals that the CRT specific rejuvenators apply a high potential between the cathode and G1. The resulting arcing exposes some "fresh" cathode surface. I'd have to believe the area would be tiny and therefore the fix very temporary. Seems like it would also be prone to throwing cathode debris at the phosphor surface, aperture mask, or gun aperture. Ugh. But now I understand the ZAP reference.   Temporary, yes. Typically the customer would get a few more months service then it became unusable due to smearing as the emission declined.   Throwing crud about didn't matter unless it created a short, which it could.   Some folk think it cleaned a bit of cathode, some thing it created electrode hotspots that scavenged gas.   I didn't like zapping at all, preferring an extra turn on the loptf heater wind. That gave a much better lasting result and didn't kill tubes.     > I was familiar with the older method that used general purpose tube testers with CRT adapters. There was no such capability with those that I was aware of -- only raising the filament voltage to overheat the cathode and boil up the emitting surface. Seems like a better chance of lasting results, if the filament survives the process.   > Funny because I owned a B&K 467 for a while, but I don't think I ever tried to use it for rejuvenation.   The worst CRT I ever did had no visible emission at all, and the tube type, sony trinitron, was known for not responding to attempts to improve emission. I gave it a large permanent heater boost after which it had plenty of emission all round. But colour tracking was lousy, although it gave a nice white the intermediate colours didn't match a healthy set at all well. That thing stayed in service many years and kept going. Occasionally it would arc over for a moment, causing green output to go way up for a few minutes then calm down. It was very much an experiment in trying to fix unfixable tubes.     NT

Terry Schwartz <tschw10117@aol.com>: Jan 05 01:39PM -0800 The Trinitrons were among the hardest CRTs to converge. Those square corners were hell to get right. Some of the Sony chassis had better convergence controls than others. I will say the last CRT Sony I owned, a 35" 220 lb behemoth, had a beautiful picture and spot-on convergence.

tabbypurr@gmail.com: Jan 05 02:48PM -0800 On Friday, 5 January 2018 21:39:47 UTC, Terry Schwartz wrote: > The Trinitrons were among the hardest CRTs to converge. Those square corners were hell to get right. Some of the Sony chassis had better convergence controls than others. I will say the last CRT Sony I owned, a 35" 220 lb behemoth, had a beautiful picture and spot-on convergence.   I have vague memories of moving little disc magnets around. But anything's better than the old delta sets with an entire panel of controls.     NT

jurb6006@gmail.com: Jan 05 09:08PM -0800 Forget all about rejuvinating. That CRT is not likely to respond like a TV CRT.   I couldn't get a real print on it but most of these things have a DC filament supply which is rectified off the flyback. Note that they are turned and the fast sweep is vertical and the slow sweep is horizontal. Just imagine the two deflection circuits swapped.   As such, off the flyback (VERTICAL OUTPUT) there should be a winding for the filament supply. There may be a filter going dry.   If the supply is alright, there is the place you put a tertiary coil in series with the winding to boost the voltage.   As far as what the voltages actually are, if the geometry is correct, the voltages are probably correct.   Rejuvination is a last resort on something like this. Even if you can get a CRT for it, the alignment is hairy and scary.

"tom" <tmiller11147@verizon.net>: Jan 06 12:34AM -0500 <jurb6006@gmail.com> wrote in message news:e2fa9391-f0a7-47f4-88d0-9c0e75a89a50@googlegroups.com... Forget all about rejuvinating. That CRT is not likely to respond like a TV CRT.   I couldn't get a real print on it but most of these things have a DC filament supply which is rectified off the flyback. Note that they are turned and the fast sweep is vertical and the slow sweep is horizontal. Just imagine the two deflection circuits swapped.   As such, off the flyback (VERTICAL OUTPUT) there should be a winding for the filament supply. There may be a filter going dry.   If the supply is alright, there is the place you put a tertiary coil in series with the winding to boost the voltage.   As far as what the voltages actually are, if the geometry is correct, the voltages are probably correct.   Rejuvination is a last resort on something like this. Even if you can get a CRT for it, the alignment is hairy and scary.     ++++++++++++++++++++++++++++++++++++++++++++   It is a color raster scanned display. OP should read up on the color display adjustments and go through the procedure. If that does not work, a new tube would be the next thing. There might even be a LCD upgrade available for less than a new tube.   We still do not know what the power supply is doing.   I bet a simple adjustment of the screens on the CRT would get some more years out of it.

jurb6006@gmail.com: Jan 06 02:34AM -0800 >"It is a color raster scanned display. "   How could you read my post and not realize that I know that ?   >"OP should read up on the color display adjustments and go through the procedure."   Why ? To fuck it up ? When you have a fault the LAST thing you do is adjust. He should CHECK the geometry. In a raster scanned display the geometry is dependent on proper voltage supplies. If the geometry is right, the voltages are right, no matter what the print says.   >"If that does not work, a new tube would be the next thing."   Sure, Keysight has them on the shelf right between the hen's teeth and the philosopher's stones.   >"There might even be a LCD upgrade available for less than a new tube. "   What planet are you from ? Are you saying that they would engineer a Tcon board and backlight assembly for an old obsolete piece of equipment they no longer support ? You'll get that right after world peace.   >"We still do not know what the power supply is doing. "   If the geometry is right, it is doing what it has to do.   >"I bet a simple adjustment of the screens on the CRT would get some more years out of it. "   Know much about CRTs ? Sure turning up the G2, which will be common to all three guns is likely to get a more usable brightness level. However, this type of video drive might start (or accelerate) the cathode stripping process.   The best bet is to increase the filament supply. Usually 10 - 20 % will do it, and it usually will last. Rejuvination might cause a G1-K short.   It can be run that way but with the likely bandwidth the circuit will have to be modified to overpeak the video output. I have done this a few times. First the G1 is tied to the K through a resistor, high enough not to cause damage due to the filament voltage but low enough that it is coupled to the cathode which stabilizes the frequency response. Then a proper location in the circuit for a peaking cap must be chosen, and of course its value. For this I would need a real print, not one of those enhanced block diagrams which seems to be the only thing I can get.   With a real print I can give more details on what to do. I am very experienced at extending the life of color CRTs, did it for decades. But this overpeaking stuff only applies if there is a short in the CRT. Most of the time it just works.   HAHA, an LCD refit for a color CRT. Thanks for the laugh.   The emgineering cost would exceed the value of the whole unit. That is before one such modification is produced. What's more, if it is a Trinitron it is a bit easier because it has a cylindrical curvature on the screen. A curved LCD screen is expensive, even if it is only curved on one axis.   Yup, be sure to let us know when you got that space/time continuum thing beat. I think ole' Bert Einstein was holding out on us.

Chris <ithinkiam@gmail.com>: Jan 05 09:06AM > slowdown of the CPU performance had no impact on the usability of the phone. > The articles I have read seem to indicate that was how the problem was > discovered by users, the performance of the phone dropped off. No?   Not as I read it.   It was discovered by the developer of a benchmarking program which collated the results of thousands of tests and noticed distinct peaks in results which matched different iOS releases. When he published his findings only then did people become outraged.   Users always complain of slowdowns, but that is hugely subjective and inverifiable.   I can see both sides of the argument. Apple were trying to extend the life of devices' batteries with minimal impact on users, although they did it in a slightly underhand way. They were trying to do the right thing and should have been more transparent about it.

harry newton <harry@is.invalid>: Dec 29 02:52PM He who is Jeff Liebermann said on Thu, 28 Dec 2017 20:34:09 -0800:   > Executive summary: Viagra makes your world blue because an enzyme > that regulates activity in your crotch happens to be very similar to > an enzyme that regulates activity in your eyes.   So the plumbing in the crotch opens up the world to your eyes?   Anyway, Jeff - did you read the fantastically *cleverly worded* apology from Apple yesterday?   December 28, 2017 A Message to Our Customers about iPhone Batteries and Performance <https://www.apple.com/iphone-battery-and-performance/>   What you have to admire is how utterly *cleverly* worded the "apology" is.   Just like a smart kid caught with his hand in the cookie jar, they are clever in what they admit and what they don't admit even though everyone knows they did it, not for the planned obsolescence (that was just a bonus), but because they put the wrong battery in the wrong phone and didn't want to honor the warranty.   Like all Apple Apologists, they can't come clean.   So they essentially apologized for the "misunderstanding". Heh heh.   They apologize for the "mis communication", heh heh...   And then they try to say all kids have their hands caught in the cookie jar, with their idiotic white paper on batteries - which completely skirts the issue that no other manufacturer on the planet was caught secretly, *permanently*, and *drastically* cutting the CPU speeds (in half!).   The fact you can replace a defective battery for $38 after January still doesn't solve the problem that they're the wrong batteries for the phones.   I *love* their clever apology - which literally screams they didn't do it for planned obsolescence (they didn't - that was just a bonus) - and yet - completely skirts the real reason they did it - which was they didn't want to honor their battery warranty.   Since it's *still* the wrong battery for the phone, it's still a crime (literally) that they force you to pay even $38 for a new battery.   Not only should the defective batteries be replaced for free, but, one year after you put the new defective battery in the phone, you're fucked again.   I only speak fact.

Sofa Slug <sofaslug@invalid.invalid>: Dec 29 10:21AM -0800 On 12/28/2017 9:58 AM, Michael A Terrell wrote: >> converters (for an AM radio) out of my Volkswagen bus. Whoever stole >> it left a dollar bill in it's place.   >    Did they ever come back for their change? ;-)   Ha Ha ...no, but later while in college, I had a 4 track car stereo that I hated. it didn't sound very good and was always eating tapes - a real POS. Instead of throwing it away, I took it out of the dash and left it on the passenger seat in a box with all the tapes.   When I returned from class later that day, the box was gone.

Stephen Wolstenholme <steve@easynn.com>: Dec 29 02:50PM On Fri, 29 Dec 2017 05:05:03 -0800 (PST), "pfjw@aol.com"   > Don't feed the troll.   You just did   -- http://www.npsnn.com

"David Farber" <farberbear.unspam@aol.com>: Dec 29 08:39AM -0800 Phil Allison wrote:   > Lots of ICs are made like this, with a penalty in the thermal > resistance spec.   > ..... Phil   I meant to post the following to the group yesterday ---------------------------------------------------------------------   First, thanks for posting that pic.   I finally found out what was causing the roadblock in my search for the LM7815/7915 in the epoxy case. STMIcroelectronics makes this part and it is available at both Mouser and Digi-Key. The difference lies in the part number for the epoxy case. The letter "M" is dropped from the part number. They are L7815CP and L7915CP. Of course those numbers don't turn up when you look for the original part number.   That being said, I think you were implying it's still better to use the metal tabbed package and use insulating hardware which will improve the thermal transfer. Is that correct?   Thanks for your reply.   -- David Farber Los Osos, CA

"David Farber" <farberbear.unspam@aol.com>: Dec 29 10:40AM -0800 Fox's Mercantile wrote:   > Just a wild guess here... > But I suspect the epoxy coating may have less thermal resistance > than a mica washer with the bare metal tab.   I suspect the difference will have minimal effect on the operation of the mixer. I'll opt for the epoxy coated device.   Thanks for your reply. -- David Farber Los Osos, CA

Nowhere Man <lost@inspace.net>: Jan 05 01:40PM -0500 Hello,   Just wonder if this item is worth the price??   https://www.ebay.com/itm/222777410635?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1558.l2649   Any thoughts??   Thanks,

Terry Schwartz <tschw10117@aol.com>: Jan 05 11:40AM -0800 On Friday, January 5, 2018 at 12:40:32 PM UTC-6, Nowhere Man wrote:   > https://www.ebay.com/itm/222777410635?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1558.l2649   > Any thoughts??   > Thanks,   Do you need it?   Google shows it starting about $170 new retail. And up.

tabbypurr@gmail.com: Jan 05 11:48AM -0800 On Friday, 5 January 2018 18:40:32 UTC, Nowhere Man wrote:   > https://www.ebay.com/itm/222777410635?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1558.l2649   > Any thoughts??   > Thanks,   spamming can backfire

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