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boroninnikolaj@gmail.com: Mar 25 06:06AM -0700 понедельник, 19 октября 2015 г., 15:33:04 UTC+6 пользователь 4thrs написал: > Has anyone got, or know where I can purchase, a schematic diagram, for this TV, Power Supply Board, CVB42001. This board is commonly used in LED TVs. I'm chasing a problem in the output voltage, that feeds the LEDs Strips. > Tks.   у меня такая же проблема,но разъём выдаёт 100v светодиоды ещё не проверял

Cydrome Leader <presence@MUNGEpanix.com>: Mar 24 09:25PM pfjw@aol.com <pfjw@aol.com> wrote: > On Tuesday, March 22, 2016 at 11:59:02 AM UTC-4, Cydrome Leader wrote: > >> The last duracell battery leakage claim I filed resulted in getting a >> prepaid credit card. Had to get an all new flashlight, but it worked out >> in the end. Not sure how they deal with more expensive stuff like test >> equipment. > > My wife once upon a time collected Fiesta Ware pottery. As you (should) know, back in the day that Fiesta first started, many of the glazes used radioactive salts for certain colors including orange, green and a few others. So, I acquired a geiger counter, military surplus, for checking that possibility. Not that the stuff was passively harmful, just that one would not wish to serve food in those pieces that were radioactive. Well, the (Eveready) batteries leaked. I sent it off to Eveready, and about a week later, received a check for $357.32 (I DO remember that number), which represented the cost of that unit when new plus the cost of my shipping the item to them. That, along with a very nice note suggesting that batteries should be removed from expensive test equipment when it is not in use to avoid inconvenience. I went back to the same source I got the first counter, and replaced it with a Navy surplus device for $75, including shipping. I gave that to my son-in-law, as he and his dad collect items that involve glazes and glass, and I now have a Civil Defense kit including scintillators and several other testers that I purchased NIB at a municipal "yard sale" for $25. Works nicely. > > I now also remove batteries from my "good" stuff if it is going down for more than a week or so.         That's a good practice. They only leak when you don't expect it. Then there are always the batteries that are good for a decade past the "good until" date. > https://en.wikipedia.org/wiki/Fiesta_(dinnerware)   Didn't know red was the radioactive color. I do like that green-ish radioactive glass from the era of uranium based home products.

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Mar 25 05:35AM -0500 "Cydrome Leader" <presence@MUNGEpanix.com> wrote in message news:nd1m0l$t15$2@reader1.panix.com...   > That's a good practice. They only leak when you don't expect it. Then > there are always the batteries that are good for a decade past the "good > until" date.   Couple years back I bought a Micronta 22-206 FET multimeter, virtually "new old stock".   Well, not quite. While everything looked pristine - Radio Shack branded batteries had been installed (1975 date code) and just left in there when the thing was boxed back up.   The batteries, a C-cell and a 9 volt, were totally flat but had never leaked. Not even a little.   Dodged a bullet on that one.   Mark Z.

"pfjw@aol.com" <pfjw@aol.com>: Mar 25 06:03AM -0700 On Friday, March 25, 2016 at 6:35:32 AM UTC-4, Mark Zacharias wrote: > leaked. Not even a little.   > Dodged a bullet on that one.   > Mark Z.   This thread lead me to check the battery-included instruments I keep at/near the bench:   B&K LCR meter Fluke DVM Transistor Analyzer ESR Meter Micronta Digital DVM (travel kit) RF/AF Signal Injector Micro Maglite 3D Maglite (AKA "Persuader")   Any one of which could be a significant inconvenience should it fail at a critical time and/or have to go away for a while.   The Geiger counter lives in the closet. It gets used perhaps twice per year.   Ah, well.   Peter Wieck Melrose Park, PA

captainvideo462009@gmail.com: Mar 24 07:51PM -0700 I need to purchase a magnifier so that I'll be able to do things like replace eproms and other small SMT's. I'm not looking to do LSI's with 150 pins Etc. Just mostly smaller stuff. For instance I currently have a board that needs an 8 pin Eprom replaced. I thought that I could do it with the magnifiers I have but the stuff is Just too small. I tried using a high res TV camera with a varifocal 3.5 to 8 mm lens but it doesn't make the image large enough. I was wondering what people are using to do this. Thanks, Lenny

"Ralph Mowery" <rmowery28146@earthlink.net>: Mar 24 11:16PM -0400 <captainvideo462009@gmail.com> wrote in message news:29a361eb-b2f1-4886-9cba-afe21278b218@googlegroups.com... I need to purchase a magnifier so that I'll be able to do things like replace eproms and other small SMT's. I'm not looking to do LSI's with 150 pins Etc. Just mostly smaller stuff. For instance I currently have a board that needs an 8 pin Eprom replaced. I thought that I could do it with the magnifiers I have but the stuff is Just too small. I tried using a high res TV camera with a varifocal 3.5 to 8 mm lens but it doesn't make the image large enough. I was wondering what people are using to do this. Thanks, Lenny       Sometimes a head band magnifier. They are only good for about 2x with any distance from the lense to the work. For just under $ 200 a stereo microscope of about 10X like this one on ebay . It is good for 10 and 20 x but the 20 x is almost too small of a field of view. It does have about 9 inch distance from the lense to the work.   Are you suing a hot air station to do the work and the paste type solder ?   400429192095

Jon Elson <elson@pico-systems.com>: Mar 24 10:29PM -0500 > magnifiers I have but the stuff is Just too small. I tried using a high > res TV camera with a varifocal 3.5 to 8 mm lens but it doesn't make the > image large enough. I was wondering what people are using to do this.   I managed to get a really good Olympus stereo microscope through an eBay seller. (i asked questions about an item he listed on eBay, and ended up purchasing a different unit from him.) I was able to make my own mount for it, and that made it a lot cheaper, as most people want the mount with the scope. I now use a large lathe chuck as the base, and it holds a block with a section of MacPherson strut as the arm. What you want is a long working distance, so you can get lights, your hands and a soldering iron all under the scope at the same time. This is what makes these special. I'd say you want a minimum of 2" working distance for soldering.   There are a fair amount of these types of microscopes floating around, with a little luck you can get a good deal.   Jon

Look165 <look165@numericable.fr>: Mar 25 11:12AM +0100 Got the same problem.   The Linear Tools 59-650-747 is ideal (about 25$) :   Multi-coated Acrylic Lenses offer a choice of 4 magnification powers via combination of fixed , flip-up and monocle lenses: 1.5, 3.0, 9.0 and 10.5 Adjustable light incorporated.   > I need to purchase a magnifier so that I'll be able to do things like replace eproms and other small SMT's.   I'm not looking to do LSI's with 150 pins Etc. Just mostly smaller stuff. For instance I currently have a board that needs an 8 pin Eprom replaced.   I thought that I could do it with the magnifiers I have but the stuff is Just too small. I tried using a high res TV camera with a varifocal 3.5 to 8 mm lens but it doesn't make the image large enough.   I was wondering what people are using to do this. Thanks, Lenny

John-Del <ohger1s@aol.com>: Mar 25 04:34AM -0700 On Friday, March 25, 2016 at 6:12:18 AM UTC-4, Look165 wrote:   > Multi-coated Acrylic Lenses offer a choice of 4 magnification powers via > combination of fixed , flip-up and monocle lenses: 1.5, 3.0, 9.0 and 10.5 > Adjustable light incorporated.   The acrylic lens scares me. I've had plastic lens visors and always scratched them and spotted them with over spray from aggressive deflux chemicals. I admit that I haven't always been very careful.   I have two pairs of OptiVisors with the blue lens inserts. The blue lens are glass while the clear lens are acrylic, which explains the price difference. I have the number 7 inserts and am going to get a 10 as my eyes are aging.   With the Opti 7s, I can put in typical plasma scan buffer ICs with no problem.

captainvideo462009@gmail.com: Mar 25 04:39AM -0700 > I need to purchase a magnifier so that I'll be able to do things like replace eproms and other small SMT's. I'm not looking to do LSI's with 150 pins Etc. Just mostly smaller stuff. For instance I currently have a board that needs an 8 pin Eprom replaced. I thought that I could do it with the magnifiers I have but the stuff is Just too small. I tried using a high res TV camera with a varifocal 3.5 to 8 mm lens but it doesn't make the image large enough. I was wondering what people are using to do this. Thanks, Lenny   I also have a headset magnifier with a pair of acrylic lenses. There is so much optical distortion through the plastic though that they're just about worthless. I have a customer who does SMT repair work and I recently had him help me. I watched him replace an 8 pin SOT for me. He had a dual lens machine like something you might see on CSI.I don't know what the magnification was but when looking into this thing it appeared as though you were looking at an 8 inch by 8 inch field of view. It was really pretty impressive. The chip took up the entire field and the spaces between the legs were very well defined. With a small enough iron and a pick it was possible to first lift each lead one at a time, remove the chip with a slight twist and then tack the new one down. I was amazed at how easy it was with adequate magnification. I think the magnification was a lot more than 10X though. I also have a headset magnifier with glass lenses that I've used for years. It has about a six inch working distance and is just slightly better than reading glasses, but looking through this guy's machine was like seeing a whole new world. Lenny

Cursitor Doom <curd@notformail.com>: Mar 25 12:11PM On Fri, 25 Mar 2016 04:39:57 -0700, captainvideo462009 wrote:   > glass lenses that I've used for years. It has about a six inch working > distance and is just slightly better than reading glasses, but looking > through this guy's machine was like seeing a whole new world.   Something like this is about as good as it's ever going to get:   http://www.ebay.com/itm/CARL-ZEISS-SURGICAL-OPERATING- MICROSCOPE-130687-/322040154682?hash=item4afb16ca3a:g:WlIAAOSwP~tW5xGT

captainvideo462009@gmail.com: Mar 25 05:54AM -0700 > I need to purchase a magnifier so that I'll be able to do things like replace eproms and other small SMT's. I'm not looking to do LSI's with 150 pins Etc. Just mostly smaller stuff. For instance I currently have a board that needs an 8 pin Eprom replaced. I thought that I could do it with the magnifiers I have but the stuff is Just too small. I tried using a high res TV camera with a varifocal 3.5 to 8 mm lens but it doesn't make the image large enough. I was wondering what people are using to do this. Thanks, Lenny   That's wonderful. Would you like to buy it for me? Lenny

N_Cook <diverse@tcp.co.uk>: Mar 25 12:35PM No reception problems , even in heavy rain, but presumably will do some time. If the dish completely rusts over , so no longer smooth, but not actually pitted with holes or distorted, would there bound to be received signal loss associated with rust rather than paint? What sort of paint over the front surface , when the rust is cleaned back ? If actual rust holes , from thinned metal that does not survive rust cleaning, then how to deal with that.?

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Mar 25 05:48AM -0500 How is it a grown man cannot understand the concept of keeping two wires separate?   Fixed a Yamaha RX-A2010 with a blown channel back in December.   Under warranty.   Big job.   Cautioned him on speaker hook-ups, gave him our hand-out sheet explaining speaker connections, which also contains explicit warnings about shorting wires etc.   Nevertheless he brought it back this week with the same channel blown again.   It was all I could do not to just go off on the guy. He admitted fooling around with the wires while the unit was powered up, and that the wires had crossed. Exactly the sort of thing I had "educated" him about.   Fucking idiot. Lucky for him Yamaha is covering it again, and we needed the work anyway.   Shit for brains god damn idiot. I knew better that this when I was sixteen fucking years old!   I'm reminded of Chevy Chase's rant in Christmas Vacation...     Mark Z.

dansabrservices@yahoo.com: Mar 25 04:32AM -0700 i'm surprised that Yamaha is covering this. Usually, customer caused failures are not covered. I recall having discussions with customers about similar types of repair requests. It seems that they think that anything that failes regardless of the cause is covered. Not the case. Physically broken parts are not usually covered. In one case, a Sony diskman (portable CD player) had the cover broken off. The owner actually thought that this would be covered under warranty. I questioned what manufaturing defect "caused" this problem and did not get an answer...   Dan

N_Cook <diverse@tcp.co.uk>: Mar 25 11:49AM On 25/03/2016 10:48, Mark Zacharias wrote:   > I'm reminded of Chevy Chase's rant in Christmas Vacation...   > Mark Z.   I have a customer who keeps breaking things, often fatally, because he picks up the nearest wallwart, having mislaid the original one, because it looks the same size black lump and the connector pushes in, so it must be ok .

Cursitor Doom <curd@notformail.com>: Mar 25 12:01PM On Fri, 25 Mar 2016 05:48:15 -0500, Mark Zacharias wrote: > Cautioned him on speaker hook-ups, gave him our hand-out sheet > explaining speaker connections, > which also contains explicit warnings about shorting wires etc.   Hey, come on. 16 ohms, 8 ohms, zero ohms; it's all the same. ;->

jurb6006@gmail.com: Mar 24 06:18PM -0700 So my sister's uWave stopped cooking. Display normal hums and all that. I have never been a microwave tech., actually never had one break. They usually catch on fire after a while.   But anyway I am hep to it, the capacitor goes bad alot, sometimes the magnetron. Sometimes triac, relay or something on the board comes loose off the solder. Normal shit.   So, I break out the old B&K 177 which has a 4 KV AC scale. The cap is rated 2,100 VAC.   I read the side with the rectifier and it is around a thousand volts. In fact less I think. I am thinking that is low. Put pur the probe on the transformer side and got an arc ! WTF ? And nothing happened. I chesked the meter, turned it to low AC and putting my finger on the probe made it read. Switched to ohms and that read as well.   So I do it again and I DID get a different result. I went to the magnetron side of the caps and got about the same reading, and then when I went to the transformer side my computer started making all kinds of noise. I do not mean 60 Hz noise, this was like a digital stream noise, probably square waves at more than one frequency.   Y'know the other day at work I got this unit the owner described as having multiple erratic and spontaneous operations. I decided to be a smartass and wrote it up as :   Complaint : Customer says multiple erratic/spontaneous operations.   Diagnosis : Unit needs exorcism.   Solution : Due to lack of holy water and Catholic Priest, changed main board.   I shit you not. But I could not blow it off because we are factory service.   Anyway, back to this uWave. On my tester, which tests at 400 mV/360 ohms impedance, the cap checks pretty good. Little bit of curve at the tips of the triangle wave but for a 0.98 uF that is to be expected with these test parameters.   So is this indicating I got a leaky magnetron ? If I can get a cap foro ten bucks I will fix it, but magnetrons are more expensive and this thing is well, it is a nice, decent performing uWave oven. Not the best but I have seen alot worse. The heat is even and the control system is not hard to deal with. It is a Magic Chef, input power is stated as 1,500 watts, so it is what, 1,300 ? Nice, small height wise but a bit wider than the really small ones.   I just think when you got something good you should try to keep it going. There is no money involved in this one.

Jon Elson <elson@pico-systems.com>: Mar 24 11:06PM -0500 > really small ones.   > I just think when you got something good you should try to keep it going. > There is no money involved in this one.   The magnetron is a hot filament vacuum diode (at least as far as the power supply is concerned). When you heat up the filament, it is supposed to conduct electrons from the cathode to the anode (RF cavity). The common failures are open or bad-burned filament, and copper hairs that short from cathode to anode. You should be able to detect the hairs with a meter, the heater can be tricky unless it just shows totally open. (sometimes the filament has shorted in several places to the cathode, so it appears to be OK (has low Ohms between the terminals) but it doesn't heat the cathode effectively.) The cathode is connected to one of the filament terminals.   Jon

DaveC <not@home.cow>: Mar 24 02:02PM -0700 > > [Jeff Lieberman]   > Please deduct one point for spelling my name wrong.   And I tried so hard to get the "Lei/Lie" bit right! (c; 2 steps forward, 1 step back... > These photos look very much like what I would expect to be hiding > under what I believe to be a lens of some sorts: > <https://www.google.com/search?q=5mm+white+led+0.5+watts&tbm=isch>   One of those images (located here):   http://tinyurl.com/j4pwvuw   looks exactly like the one in my light. It's squat, with very (relatively) large yellow die(?) in the center. I don't think there's a separate lens. Maybe it's molded to focus the light (integral lens)? Wish I could find that LED other than @ Alibaba...   Ah-HAH! From that Alibaba image page: "strawhat LED". Search turns up similar-looking LEDs. Searching on the terms "strawhat" and "dimple" tells me that this form-factor is for radial distribution of the light, not throwing a beam. Which means the flashlight designer wanted the reflector to shape the beam, not the LED.   So I'm looking for one of these types.   Thanks.   (Why are my search skills so crap? Google keeps returning Manga images and cartoon faces...)

not@telling.you.invalid (Computer Nerd Kev): Mar 24 09:44PM > dimmer. Shine the light at something bright, and the flashlight runs > at full brightness. Shine it at something in the dark, and it goes to > fairly dim.   Hmm, that sounds like a good idea to put in my planned LED torch project, which was going to have a manual dimmer anyway. I guess an LDR would be suitable? Maybe mount it in a small tube to make it directional?   I guess I'll have to find an LDR and wave it around with my multimeter attached. Ahh, the dignity of research. :)   -- __ __ #_ < |\| |< _#

John Robertson <spam@flippers.com>: Mar 24 10:28AM -0700 On 03/24/2016 1:44 AM, Top Cat wrote: >> www.flippers.com >> "Old pinballers never die, they just flip out."   > Hi John, if I could look at what you have that might be the answer to my prayers. I can't find your e-mail though. Am I being dense? Is it glaring at me somewhere? Cheers.   spam@flipp...om works - just use the email responder. Or go to my web site - listed in my signature and find my email there.   Still trying to get legible copies. I have 10 different B&W Taito monitor schematics!   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

John-Del <ohger1s@aol.com>: Mar 24 10:46AM -0700 On Thursday, March 24, 2016 at 10:15:40 AM UTC-4, Top Cat wrote:   > > Regards > > Frank IZ8DWF   > I've had it out and cleaned the cup etc, but didn't think to test it unconnected.   Don't waste your time trying. CRTs don't short that way. If the CRT is full of air, the tube will arc loudly. You could ground the second anode cup to the metal frame and it still won't smoke the flyback. Any secondary short will destroy the horiz output or open the B+ fuse (or both) way before the flyback can smoke. If the flyback smokes, it's bad.

John Robertson <spam@flippers.com>: Mar 24 10:53AM -0700 On 03/24/2016 7:15 AM, Top Cat wrote:   >> Regards >> Frank IZ8DWF   > I've had it out and cleaned the cup etc, but didn't think to test it unconnected.   Why do you insist that the flyback is bad? Have you tested it with Bob Parker's LOPT/Flyback ring tester? Or is it physically broken?   Bob's meter can be bought from us (read the assembly manual as that goes over the theory):   http://www.flippers.com/catalog/product_info.php/blue-flybacklopt-ring-tester-p-19   and others of course.   John :-#)# -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

frank <frank@invalid.net>: Mar 24 07:27PM > cup to the metal frame and it still won't smoke the flyback. Any secondary > short will destroy the horiz output or open the B+ fuse (or both) way > before the flyback can smoke. If the flyback smokes, it's bad.   ok I stand corrected :-) I've never happened to find a bad flyback anyway. Why the B+ fuse don't open (or the output transistor blows) when the transformer primary is shorted? The load should be quite far away from normal. Maybe it has other secondaries with shorted loads?   Frank IZ8DWF

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