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Thread: Mitsubishi WS65807 Hourglass affect |
    
New member Username: Dmcd327
Post Number: 4
Registered: Feb-07
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| Posted on Saturday, February 24, 2007 - 04:02 pm: |
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Forgot 1 thing. I've been looking at calibration DVD's. So far it's down to AVIA or DVE. Which one is better? Is there another one out there that I'm overlooking? Any advice is appreciated. Thanks. |
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Relevant Product Info
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New member Username: Veasnalong
Fresno,
Calofornia
Usa
Post Number: 1
Registered: Feb-07
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| Posted on Sunday, February 25, 2007 - 11:17 am: |
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Derrell,
If you read Thread all above seems to have issued with STK chip although STK392-570 run more hotter. At 100khz temp. 60-65 degree C.
In my case i just resolder bad joint and replaced some Caps that near heat sink I did check some of those caps found out some of them read Hi ESR (equivalent series resistor)due to head stress so i replaced them now my Misubishi SW-55809 back to normal have not replace the chip yet. |
New member Username: Veasnalong
Fresno,
Calofornia
Usa
Post Number: 2
Registered: Feb-07
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| Posted on Sunday, February 25, 2007 - 11:33 am: |
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Hi SKSLVNV,
Your name Must be Steve Correct?
I am new to this site after read all post above and seem to see you the only one that have more knowledg and answer all question. This is good that you every one out with (hint)and hope they all know as far as Hi voltage CKT and be able to do some simple thing by try to some money.
Veasna, |
New member Username: Bigun22
Boulder ,
Colorado
Usa
Post Number: 1
Registered: Mar-07
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| Posted on Friday, March 02, 2007 - 04:00 pm: |
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Hi, I am new to this forum. I have a WT46809 with the convergence problem. I purchased 2 of the recommended ICs and was already to start the repair. I opened the front and back of the TV but I am not sure how to remove the center board. Does anyone have a process to follow to remove the board. Is this something detailed in a shop manual?
Thanks
John |
Bronze Member Username: Veasnalong
Post Number: 26
Registered: Feb-07
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| Posted on Saturday, March 03, 2007 - 01:01 pm: |
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John,
Once you pull panel ( Board supporter )and disconnect all plugs and pup up the ribbon cable plug type that connect to the outer board. then you will see all screw that hold the board down. One thing in mine you must understand Hi voltage ckt. |
Bronze Member Username: Veasnalong
Post Number: 27
Registered: Feb-07
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| Posted on Saturday, March 03, 2007 - 01:20 pm: |
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John,
For pop up ribbon cable header see picture must disconnect all around the board.
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New member Username: Bigun22
Boulder ,
Colorado
Usa
Post Number: 2
Registered: Mar-07
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| Posted on Monday, March 05, 2007 - 10:51 am: |
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Veasna
Thanks for the information. I have one more question. Do I remove the whole light box to get to the board or is it better to remove just the board. I need to take the board to a certified person who does soldering.
Thanks |
Bronze Member Username: Veasnalong
Post Number: 28
Registered: Feb-07
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| Posted on Monday, March 05, 2007 - 11:19 am: |
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Just remove the whole Plastic board holder slide out through the back but there are some (key clip)toward the front by press on them to release inorder to pull it out and unplug the wire connector then unscrew to remove the board. |
New member Username: Adpanther
San Jose,
CA
Post Number: 3
Registered: Jan-07
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| Posted on Friday, March 09, 2007 - 11:35 am: |
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WARNING Like the previous poster my credit card info was misused in the midwest after I ordered from ELECTRONIX.COM I WAS ALSO CHARGED $20.50 WITH A PHONE NUMBER IN THE TRANSACTION LINE OUT OF MA Be careful folks. Anyone else have this experience??? |
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Bronze Member Username: Veasnalong
Post Number: 31
Registered: Feb-07
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| Posted on Friday, March 09, 2007 - 02:54 pm: |
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Dave,
Thank you for let us know for what ever happen to your credit card. Most of the time I order parts from MCM Electronic.
Again Thank you very much |
New member Username: Dmcd327
Post Number: 5
Registered: Feb-07
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| Posted on Saturday, March 10, 2007 - 02:46 pm: |
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Dave, YES IT HAPPENED TO ME TOO JUST RECENTLY. Ordered my part from Electronix.com. A few days later I had a charge from Toolware Online for $26.99. I traced it down to a company called Tools4you. I sent them an email and of course no reply. I tried calling their phone # and it says its an availble maxemail. I think thats what it said, hard to understand the message. In the meantime I called my bank and disputed the charge. Still currently waiting for the paperwork to get it charged off, but will be no problem. Just a pain! |
New member Username: Mike409
Post Number: 2
Registered: Jan-07
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| Posted on Tuesday, March 13, 2007 - 12:06 am: |
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I just want to thank Steve of this forum and larry dillon from Techlore. I had resolderd 5 pins on my horizontal STK to fix a convergence problem - see above. A month later the TV went south blew a fuse and went into short circuit protect mode.
steve suggested -... NOTHING external can cause a convergence failure. You've likely blown a fuse or fuses that provide power to the STK IC's. This is the result of you not changing the IC's in the first place. If you're lucky, nothing more serious has occured and you can replace the IC's and fuses and everything will be ok. Don't attempt any adjustments to the tech menu or you will not be able to get it back in to alignment.
me.... Thanks Steve,
I tested voltage to the IC's 24+ was there but 24- was absent on my WT42315. I repalced the fuse and the IC, which I bought from audio lab of GA. The TV stayed on but the picture was blue as was all the text.
I bought two sets of modules one from MCM and a set from audio lab of GA. the latter company said the STK's were purchased direct form Sanyo. They had STK394-250A-E a lead free version - although the STK's I received had STK394-250A written on them. the minus 24 volt pico fuse on the power supply had blow. I replaced the STK's (with the Audio lab of GA IC's) and the fuse. the TV stays powered up, but the picture is Blue as is the text in the set up menu. Could it be that the IC's are not up to snuff? Any suggestions would be appreciated. The IC's were easier to change than I had thought. I feel comfortable replacing PCB components.
You never said what model set you had and I'm not familiar with the IC part numbers you provided. What model number is this anyway???? Alot of the advice I've given is not necessarily applicable to other models, though in general they are similar.
The IC's have nothing to do with a blue picture. I would suspect that you either don't have a plug properly seated or perhaps a cable has come loose going to one of the CRT boards. You should go over every plug that you disconnected and be certain that all are correct. In particular, pay attention to the short jumper plugs between the boards. There are other wires that can come unplugged while sliding out the chassis. You need to be sure that all three CRT's are glowing. The CRT's should have an orange glow in the neck indicating that the heaters are lit. If only the blue CRT is glowing, then that is your problem. I don't have any other ideas without a model number.
this might be all jumbled up but my wife is anxious to watch 24 on HD again and I'm not going back to edit what i pasted together
thanks again |
New member Username: Mike409
Post Number: 3
Registered: Jan-07
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| Posted on Tuesday, March 13, 2007 - 02:48 am: |
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gosh the above post was a mess. I repalced the IC's and the fuse, but the pic was blue as was the menu text. Steves suggested that a socket had become unplugged when sliding in and out the light box. Indeed, a socket had become half unpluged on teh video board. After reseating the plug and buttoning up the
tv - viola, the pic is almost perfect. I'm doing the hey shorty its your birthday day dance and my son is saying OH dad - you are such a geek....
a couple of points are worth mentioning.
Steve has suggested not cutting the IC pins to make removeing the chips more facile is a BAD IDEA. Fist I have to say that a set of magnifying glassss are a must to IC removal and replacemtns. Second using ,025 inch desoldering braid to remove the solder, leaves the chip vertually unsoldered from the beaord. A simple touch with the soldering iron on pins that remain attached will dislodge them from the board. the chps is easily removed using this method. Also .025 inch solder is necessary to resolder the new IC's into place. what would cost me 500 buck for a tech to come and fix I did for under 50 bucks - which inclueds IC's , pico fuse , magnifying head set and solder. BTW, i HAVE A SECOND SET OF ic'S IN MY FILE CABINET. yrs down the road when the IC's fail and there are no replacemtn IC on the market I will have parts. One last thing, the pico fuse was located on the power board, F9A05.
A 5 amp 25V pico fuse (green in the enclosed pic).
Thanks to all who post here. I hope my blog helped.  |
New member Username: Jshoe
Cincinnati,
Ohio
Usa
Post Number: 1
Registered: Mar-07
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| Posted on Thursday, March 15, 2007 - 01:00 am: |
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Read thru all the posts on the convergence problems. Had one myself and fixed it. Wanted to get some feedback on whether its worth installing a 12 vdc fan on these heat sinks. Does anyone have any knowledge or experience on this idea. Thanks, John |
New member Username: Drabdr
Post Number: 1
Registered: Mar-07
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| Posted on Friday, March 16, 2007 - 12:54 pm: |
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This site was a huge help to me, so I figured I would add just a bit. I am not an electronics expert, so that is my angle. Sorry for long post, but figured I would give some detail.
Classic symptoms: the picture was OK in the middle, and distorted on the left and right side. Using operator controls, I could not line the red convergence up; blue was off a little bit.
I purchased the chips, flux, and heat transfer paste. I had a good solder tool, solder, and the handtools. Do get several phillips screwdrivers of different sizes.
Mitsubishi
WT-46809
Date: October 2001
1. Unplug the TV. Avoid as many electronic devices as possible while going through this entire process. Observe proper ESD practices.
2. Unplug cables from TV. If you have more than one input, you might want to mark these, so you're not guessing later.
3. Remove back brown panel from TV (approximately 12 screws). Remove front speaker grill. This is attached with plastic "pop-ins". Sitting in front of the TV, pull the outside bottom of the grill on each side at the same time. The panel should pop out so you can remove it.
4. Remove the front black panel (six or eight screws). BE CAREFUL, reach in and untie the wires from the twisties (pictured in previous posts). You will need the slack from the wires to pull out the tray. You should find yourself untying about 10 twisties.
6. The three main cards are mounted in a tray that can slide out. Remove three-four black screws (app. 3” long) from the outside trim that holds down the tray. There is a bracket attached (triangle shaped) to the cable connection board that also needs to be removed (back of TV).
7. There are two, small black teeth on the front of the tray under the screen. Those should be pushed up with the finger. Making sure you don't pull any of the wires too tight, work the tray out from the TV. Please go slow on this. If you feel some tension, there is a wire you did not untie.
8. Once the tray has slid out enough to do your work, Remove the board mounting screws. There were three on the back, two on the front, and one in the middle. There is a silver box on the left on the card (approx. 5"x1"x4") that the two mounting screws needed to be removed.
9. Remove the bracket (three screws) that press the chips to the heat sink. Remove the three screws from the heat sink that mount to the board. You should feel the board loose. If it is not, you missed a mounting screw.
10. Pop the white cable connectors up by using a small flat screwdriver on the side with a small lip. Remove the rest of the jumpers. I found no need to label these, as they were unique in size, and/or had unique labeling on them. You may want to label them to be safe.
11. Remove the board and do the deed. NOTE: I am about a 3 (from 1 to 10) on soldering. It is to your advantage to find a friend, coworker, neighbor, etc. who is experienced with soldering to at least help look over what you do. It was worth it for me. I replaced the chips, used transfer paste, reversed this process, and now my family is happy!! Don't forget to go into the basic operator menu and adjust the convergence. |
New member Username: Drabdr
Post Number: 2
Registered: Mar-07
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| Posted on Friday, March 16, 2007 - 04:10 pm: |
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Well.. my TV worked perfectly for about four hours. Suddenly, the colors started flickering on the screen. They flickered fairly violently, then the power went off. The TV will not turn back on.
Not sure what I could have missed. The solder work was checked by a trained tech. Could one of the chips have gone bad?
Given a preview of the previous posts, would it be a fuse? What would cause the fuse to blow?
Any advice would be greatly appreciated. |
Bronze Member Username: Veasnalong
Post Number: 32
Registered: Feb-07
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| Posted on Saturday, March 17, 2007 - 12:40 am: |
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Brad,
Where did you buy the IC from? Is is original Sanyo parts? I you buy form MCM Electornic they carry original Brand. If you get from electronix.com then genaric. Also Problem could be not enough heat sink compound behind convergen IC or not set flat to heat sink cause this chip to burn out (internal shorted)this Chip run very hot. Need to check to see any open Fuse more then likly you do have Fuse open . |
Bronze Member Username: Veasnalong
Post Number: 33
Registered: Feb-07
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| Posted on Saturday, March 17, 2007 - 12:46 am: |
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Brad,
Never mine my spelling after I post found out some of my spelling were mess up. |
New member Username: Drabdr
Post Number: 3
Registered: Mar-07
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| Posted on Monday, March 19, 2007 - 12:51 pm: |
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Thanks, Veasna. I will purchase some new chips, and look into a potential fuse being blown. I also got some help offline that I greatly appreciate. |
New member Username: Dave_s
Post Number: 1
Registered: Mar-07
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| Posted on Saturday, March 24, 2007 - 07:40 pm: |
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I have a 5 year old Mitsubishi WS-55819 projection TV. Last night the center of my screen went black. The picture is visble, but is split in two halves on either side of the now dark center and is displayed with blue and red verticle bands. I pulled the cover off the back and saw that all three bulbs were on. I don't want to spend a lot of money to have a tech come out and recommend a repair that is not cost effective. Any ideas as to what the problem might be? Any assistance would be appreciated. |
New member Username: Mercuryboarder
Post Number: 1
Registered: Apr-07
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| Posted on Sunday, April 01, 2007 - 10:49 pm: |
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Hello Everyone!
I really appreciate all the hard work that has been put into this forum and this thread in particular. I've thoroughly read the entire thread and I'm not entirely convinced that I've found a solution. I just got a WT-46807 from someone who said that a tech looked at it and told them "the blue had leaked onto a circuit board and the board would have to be replaced."
Just for kicks I took it home and plugged it in. The set worked great for about 3 hours with no convergence issues. Then the set clicked off and began the above mentioned "on for 2 seconds then off" problem.
I get a "21 x-ray protect circuit" error code. I realize that this thread is concerning a different problem but it seems to be possibly related? Any help would be very much appreciated as I absolutely do not have to $800 the tech quoted to fix it.
Thank you all!
-Mike D |
Bronze Member Username: Skslvnv
Post Number: 38
Registered: Mar-06
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| Posted on Monday, April 02, 2007 - 01:27 am: |
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Mike,
You are describing a leak of CRT coolant on to the board. The coolant is conductive and corrosive. Many times the board is simply not repairable if a large amount of coolant has leaked on to it. You also need to replace the blue CRT to insure no further leaks. My advice... spend your money and your time on a new TV. |
New member Username: Mercuryboarder
Post Number: 2
Registered: Apr-07
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| Posted on Monday, April 02, 2007 - 09:59 pm: |
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Steve,
Thank you so much for your advise. HOWEVER....lol. I checked it all out and I don't see any evidance of said coolant leak.
Now, I'm not calling anyone a liar but I'm wondering if there are any other possible scenarios that might produce the same results. The only reason I have for holding out is the number of postings in which the hired repair guy was wrong. And usually to his advantage.
Again I really appreciate your help and I'm NOT saying I don't believe you. I'm just hopeful till the end I guess. Maybe those 2 obscure fuses that aren't on the chart? Hmmmm....
Also, I originally thought the only problem with the TV was that the DTV inputs did't work. I arrived at this conclusion by plugging my xbox into the DTV input first and there was no blue in the picture. Then I plugged it into one of the other component inputs for 480i and it worked flawlessly. Just thought that might shed some light..... Anyways....
Thank you!
-Mike D |
Bronze Member Username: Skslvnv
Post Number: 39
Registered: Mar-06
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| Posted on Tuesday, April 03, 2007 - 01:02 pm: |
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Mike,
PTV CRT coolant is a colorless, Ethylene Glycol and water formula (similar to anti-freeze used in cars). It’s slightly viscous and feels like light oil in consistency. Most of the time, there’s only a small amount of coolant that leaks, just a drop at a time on to the board. It's not always easy to see evidence of a leak. Sometimes you can see what appears to be oil stains on the particle board under and around the main chassis.
Damage to the board occurs because of the design of surface mount circuit boards. There are hundreds of components, very densely populated on these boards. The coolant is conductive and corrosive. It gets between components and the circuit board and literally eats up the traces. As I said, many times you have a hard time even seeing where the damage is.
It’s always possible that a tech gave a false diagnosis to bail out of a difficult repair, but the problem is common enough that I would take it seriously. Also, because of the random nature of damage caused by this kind of failure, there can be many different symptoms and the symptoms can change as the the coolant evaporates or migrates around on the board. The only reliable repair for this problem is replacement of the board and the CRT, very costly to say the least. Bottom line, your own description of changing symptoms is consistent with a coolant leak. Anything is possible, but my money is on the leak and you may be wasting your time even trying.
Steve |
New member Username: Mercuryboarder
Post Number: 3
Registered: Apr-07
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| Posted on Thursday, April 05, 2007 - 03:57 am: |
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Steve,
Once again I really want to thank you for your advise. My new plan of action is just to watch the free tv until it either a) explodes or b) finds itself on craig's list as a parts unit once it has been replaced. Either way my expectations are not high so my disappointment level will be relatively low when it does go.
I am going to rig up some sort of catch basin....thingy.... in an attempt to stretch the life of the set as far as possible. It's an idea someone else on here had.
Anyways, if there's anything you ever need advise on or you maybe want the parts once this thing goes completely tits up just let me know. I know a little about everything. Well, everything excluding mitsubishi projection tv's that is. 
Thanks again!
-Mike D |
New member Username: Hostingitall
Post Number: 5
Registered: Apr-07
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| Posted on Thursday, April 05, 2007 - 10:32 pm: |
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can anywhere tell me where to find this part... having the issue where the TV will not power on with the newly installed STK chips, looking for a replacement or a solution to fix will attach a picture. its for a MITSU VS-60703 |
New member Username: Pyrex
Post Number: 1
Registered: Apr-07
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| Posted on Saturday, April 07, 2007 - 03:32 am: |
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Hey everyone... I've read all the posts many times... and I'm going to go ahead and make my first one. I disassembled my mitsu about a month ago, and tried re soldering all the pins on my IC's... it worked... for about ~15 minutes and then went to crap again. The problem started very very slight with brightness flicker, and progressed into convergence variation, then to a very slight convergence pull on the left, to a more drastic one, and as the months went on the pincushion (hourglass) effect began as it stays on longer. I'm very experience with computers, and electronics in general.... however this TV did impress me with it's complexity. I found that these IC's create an unbelievable amount of heat... Mitsubishi chose to use passive cooling... bad idea. These IC's are reaching temperatures around 270* - that is ridiculous. No matter how high quality your IC's are, they cannot withstand heat like this, you will literally burn your hand on the heatsink. The combination of terrible thermal compound (the white stuff slopped all over) and a completely unfinished surface on an aluminum heatsink is childish. My measured temperature off of the IC's were 121* C via infrared laser thermometer. I removed the trashy aluminum abomination and lapped the contact surface. Glab a sheet of finished glass plate, and start with 400 grit sand paper.. lay it flat on the glass sheet and place the heatsink on the sandpaper and move the heatsink, not the paper. Work your way to 1000 grit, and then polish the surface to a mirror finish... this will flatten the aluminum and remove air gaps between the heat sink and the IC.... air is an insulator... not what you want. Rinse & repeat for the IC contact side as well (don't actually get it wet - figure of speech) Also go to your local computer store and pick up "Arctic Silver 5" also called AS5.. it is a 99.99% pure silver thermal compound that will transfer heat light years better than that white junk. Once both contact sides are polished to a glass like finish, take your AS5 and apply a small line approx 2" and flatten the compound out with a razor blade... the less the better... we polished for a reason.. the less compound between the IC and the heatsink, the better the heat transfer. After completing this arduous task.. I noticed the heatsink heated up a full 25 minutes sooner than before... You're probably asking yourself.. what the hell was all this for, now I've got even more of a problem! - actually you just solved the first portion - transferring the heat effectively out of the IC and into the heat sink - the next part is to remove the heat from the heatsink... which you will have to utilize active cooling methods. I suggest a 120mm 12v DC fan, you can find them for real cheap (~$8) from any electronics store. The larger the fan, the more CFM at less RPM... basically it's quieter... which is important. A 120mm fan will be almost silent.. and move a good amount of air. Using your multimeter locate a 12v DC circuit, and tap into it.. make sure the circuit is open when the TV is powered off.. don't want the fan running 24/7 - only when the TV is on... you can find a circuit like this at the back of the center board - service port area. Place the fan directly on TOP of the heatsink - so it overhangs on each side of the CENTER of the heatsink... the purpose here is to push air through the air vanes on the heatsink... more surface area = more heat transfer - more effective cooling. Also, the overhang will benefit the IC's by directly blowing air over them, and on the reverse side, you will cool the other heat sinks on the board.
Now.. results? why did I do all this?
Remember, my IC's had already gone through severe electro migration.. the heat destroys IC's... and the degradation of my convergence over the months was evidence of this. it was getting BAD.
laser temps now off the same IC with active cooling are 48-52c -- a 51.2% decrease in overall heat... insanity.
believe it or not, this helped my already severely damaged IC's from showing any visible problems for 3 additional months... just to prove the difference I would power the TV on, go to a high def signal (they hate these) and watch the picture hourglass... fire up the fan and it was completely gone in 5 minutes. Now, the IC's were already damaged, but it just shows how much of a difference these steps make.
So, I submit in retrospect... your damaged IC's and convergence problems ARE from bad solder joints...caused by HEAT and a poorly affixed heat sink. when you fire the TV up the heat from the IC's is so unbearable it causes the solder to break down and loose it's malleability, when the TV is transported or moved, the loose heatsink cracks the brittle joints caused by the heat... and then you have increased resistance on the circuit.. coupled with even MORE heat now.. and a terrible passive cooling system.. you have your disaster waiting to happen.
Actively cool you new IC's people... you will never have another problem again, and I can promise you that. |
New member Username: Tonys101
Post Number: 1
Registered: Apr-07
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| Posted on Monday, April 09, 2007 - 01:18 pm: |
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Hello, I have read the whole thread a lot of useful information. Thanks to all the people who have offered suggestions and posted useful tips. I have a Mitsubishi ws-65907 diamond series that I bought in 2001. 2 days back it was working fine when I shut it off. When I put it on there is no sound and picture. I tried switching the inputs and channel but no response. Searching on this forum I found a lot of good information. I am some background in electronics and pretty good soldering skills.
I did trouble shooting using the information in the forum posting using LED Diagnostics and found the error code as "12" - no error has occurred. Still there is no picture and sound. What could be wrong? Any help would be greatly appreciated. Thanks. |
New member Username: Joerich
Post Number: 2
Registered: Apr-07
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| Posted on Tuesday, April 10, 2007 - 01:10 am: |
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Hi. The convergence amp in my Samsung HDTV (HCN653W) went out on me a few weeks ago. I had a professional pick the tv up and do the repair for me. Once I got the tv back, I noticed that it doeesn't play HD like it used to.
Every HD channel I watch is letterboxed, and the picture is squashed down vertically, and therefore the picture looks fat and stretched out horizontally. I've also noticed that there isn't a delay when I switch from SD to HD -- before the repair, there was a slight pause when changing from an SD to an HD channel, and the blue info guide (from the Charter Communications box) would also change shape - this no longer happens.
It seems that whatever settings that tell the tv how to handle an HD signal have been changed. I called the professional that repaired my tv, but he says he has no idea of what I'm talking about, and that HD is always letterboxed!?! (Never using him again.)
Anyways, I have a service manual, but it doesn't say anything about this problem. I've played around with changing some of the settings in the service menu, but haven't found anything that works. (The service manual doesn't really define any of the options found in the service menu, it only gives the default settings.)
Anyone have any ideas on how to fix this? Or know anywhere I can look to learn more about some of these service menu settings (i.e., 3D-COMB Filter, AGC, Burst Screen, Letter Box, SYSTEM VSD 480p, etc.) Thanks in advance! |
Bronze Member Username: Skslvnv
Post Number: 40
Registered: Mar-06
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| Posted on Tuesday, April 10, 2007 - 12:02 pm: |
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CJ... While I appreciate your engineering approach and especially your efforts to measure and record the actual parameters of the problem, I believe that most of what you suggest is out of the reach of the average person reading this forum. I've already commented on why you shouldn't place fans inside of a projection TV. Others can read back through the archives and decide for themselves if they feel it's worth the effort. However, I do take exception with your suggestion to use silver based thermal compound. Since that product is electrically conductive, I would never recommend its use by inexperienced individuals. The chances of getting the product on the IC leads or circuit board are high and could create shorts and additional failures. The silicone based products work just fine and in most cases, replacing the IC's one time (if it’s done right) in the life of the set is all that's required. All projection sets have a limited CRT life expectancy, 5-7 years on average. Most, if not all of the sets being discussed here are nearing that life expectancy. The effort made to modify the design is outweighed by the fact that these sets are only going to be around for a few more years.
Tony… The diagnostic codes provided by Mitsubishi are not very comprehensive and of little help. As you note, the #12 code is no problem found. You have to provide MUCH more information in order to attempt a diagnosis. There are at least 10 different directions one can go with a no sound, no picture symptom. Is the power light coming on? Does the power light stay on? Do you hear the power relays clicking and then shutting off? Is there any light on the screen at all? Can you bring up the on screen menu? Is there high voltage on the CRT’s? Are the CRT heaters lighting up? Is there any noise at all coming from the speakers? What are you using as video and audio source? Have you confirmed all of your external connections are good? Not trying to give you a hard time, but these sets are way too complicated to give such simple answers without more information on the symptoms. Your problems are not likely caused by failure of the convergence ICs.
Joe… In most projection sets, the high definition convergence adjustments are different than the standard definition adjustments. In other words, the standard definition can work fine while the HD is screwed up. Your servicer obviously did not perform the convergence adjustments for HD. I would call them back immediately and have them fix the problem. There is no way an inexperienced person can perform the technician convergence settings. |
Bronze Member Username: Skslvnv
Post Number: 41
Registered: Mar-06
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| Posted on Tuesday, April 10, 2007 - 12:18 pm: |
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Joe... One more thought... If your sevicer is not a factory authorized Samsung servicer, he may have no idea how to resolve your problem. If he is a factory authorized servicer, I would contact Samsung customer service and get them to help you with the servicer. I would not delay in getting this problem resolved, as reduced sweep symptoms can cause unrepairable damage to the CRT's. I would further suggest two things. 1. Do not use the set in HD mode until you get this resolved. 2. PLEASE do not adjust any of the technician adjustments in the manual. You cannot perform these adjustments without the proper equipment and experience to know what you are doing. If Samsung or the servicer learns that you have a service manual, they may void your warranty and blame you for the problems. |
New member Username: Pyrex
Post Number: 2
Registered: Apr-07
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| Posted on Tuesday, April 10, 2007 - 07:59 pm: |
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SKSLVNV - Yes, I agree as well it is a relatively complex and intricate solution to the issue, and yes I also agree with the life expectancy curve compared to the labor involved. I was after a solution to the problem that made the IC's the way they were... I just refuse to rig the problem up with a new set of victims. It's possible damaged IC's would adversely effect other components increasing the probability of pre-mature CRT failure. I certainly hope 5-7 years is exaggerating however, I see no reason for any cathode ray tube to have such a short life... there must be further variables causing this short life.. it's probably cooling or cheap power management and voltage regulation... if you have any insight, let me know.. I'm interested. |
New member Username: Tonys101
Post Number: 2
Registered: Apr-07
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| Posted on Tuesday, April 10, 2007 - 08:37 pm: |
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Skslvnv,
Is the power light coming on?
Yes, it does come on.
Does the power light stay on?
Yes it does stay on. But last couple of days, I found that the picture came back with no sound. After I switched it on again, the picture is all garbeled with curved slines going horizontally with no sound. The horizontal likes keep chaging positions. Sometimes I can read the inpute definition on the screen (Standard Input A).
Do you hear the power relays clicking and then shutting off?
Yes, now the relays click and then go off when I turn it off.
Is there any light on the screen at all?
Yes now there are blue horizontal curved lines across the screen.
Can you bring up the on screen menu?
No. The menu does not come up.
Is there high voltage on the CRT�s? Are the CRT heaters lighting up?
Yes the CRTs light up and I can see them glow.
Is there any noise at all coming from the speakers?
Nothing at all.
What are you using as video and audio source?
I am using the standard RF cable as the input source.
Have you confirmed all of your external connections are good?
Yes, I check have all connections and they look good. In fact I have unplugged all the other connections from the Audio receiver and using only the RF input as a connection to debug.
Thanks a lot for your help.
Tony |
New member Username: Carmaster
Post Number: 5
Registered: Apr-07
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| Posted on Tuesday, April 10, 2007 - 08:44 pm: |
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my c3po keeps breaking down, a girl keeps coming on saying she needs my help but immediately the projection goes off... IF ANYONE CAN HELP ME I AM IN DESPERATE NEED OF IT!!! |
New member Username: Tonys101
Post Number: 3
Registered: Apr-07
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| Posted on Tuesday, April 10, 2007 - 10:04 pm: |
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SKSLVNV -
I checked again and now the blue lines have centralized to the center like a bow tie - picture attached -
Thanks for your help.
Tony  |
Bronze Member Username: Skslvnv
Post Number: 42
Registered: Mar-06
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| Posted on Tuesday, April 10, 2007 - 10:24 pm: |
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CJ...
Projection CRTs have an average life expectancy of 10,000 hours before a significant loss in luminance output occurs. If the average person watches television for four hours a day, 365 days a year for 7 years, they will have 10,220 hours on their set. If they watch their set 6 hours a day, 365 days a year for 5 years they will have 10,950 hours on their set. A projection set in a sports bar or restaurant can be on 12+ hours a day and they tend to last only 2-3 years. Obviously, if someone watches TV for just a few hours a day average, their life expectancy is going to be higher. Either way, I always advise people not to have a projection set on unless someone is actually watching the TV.
The reasons that projection CRTs have such a short life expectancy are simple. First, in order to obtain maximum brightness in a rear projection design, the manufacturers have designed the CRT's to operate at near maximum beam current. High beam current also means higher temperatures and this is much harder on the internal components of the electron gun (primarily the heater and cathode). This leads to a shorter life expectancy for these CRTs compared to standard, direct view CRTs. Second, as projection CRT's age, the internal phosphors are burned to a dark brown color. This will eventually affect the brightness output. Since all three CRTs operate together, they generally turn brown at the same rate and the diminished brightness output is not readily apparent. Phosphor burning is the main reason why you cannot replace one CRT in a projection set after a few thousand hours. In these situations, there is no way to balance the red, blue and green colors and get an acceptable picture, no matter which CRT you replace.
The issue of phosphor burn is also significant in what a person chooses to watch on their TV. If you leave a projection set on a channel that displays a constant pattern (like news or shopping channels), that pattern will be burned into one or more CRTs forever. Certain video games can have the same damaging affect. This damage can happen in as little as a few days! Many manufacturers have limited the customer adjustable brightness range to help prevent these problems. There is no fix for phosphor burn except to replace the CRTs.
Finally, these are the main reasons why I always advise people NOT to mess with the adjustments on their sets without having the knowledge and experience to understand what they are doing. By misadjusting the red, green and blue levels, you can seriously diminish the life expectancy of your set. I’m sure this is much more than you wanted to know, but hopefully this will be of benefit to you and others as well.
Steve |
Bronze Member Username: Skslvnv
Post Number: 43
Registered: Mar-06
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| Posted on Tuesday, April 10, 2007 - 11:52 pm: |
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Tony,
Your photo indicates a serious sweep failure affecting both the vertical and horizontal sweep. It could have many causes, including the CRT coolant leak I discussed a few posts back. A coolant leak will cause multiple symptoms and it appears you have more than one thing wrong here. It could also be a failure in the power supply or even bad solder connections. Usually, the set would shut down in this situation and not allow any kind of picture to be on the screen. This is to prevent the CRT phosphor damage I mentioned in the previous post. I'm afraid your problem is the kind that only an expert can handle. If you do something wrong in troubleshooting, you could easily damage the CRTs.(if it hasn't already happened). The set is in the age range where I would ask myself this question... "Am I willing to spend a considerable amount of money on a set that may only have a few years left?" Only you can answer that question, but $300-$500 would make a nice down payment on a new set.
Steve |
New member Username: Vin1x
Post Number: 2
Registered: Mar-07
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| Posted on Wednesday, April 11, 2007 - 01:18 am: |
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Hi Steve,
I have gone thru some of your responses and found them very informative. I am attaching a picture of my TV as well. Is this the hourglass effect folks are referring here? I have Mitsubishi VS50501A and picture is blurry as well. Can this be corrected by changing 2 IC’s STK392-570. I would say my soldering skills might be ok, haven't done that since college. If i understand the procedure, I plan to attempt repairing and if not successful discard the TV.
Appreciate your help!
Vin |
Bronze Member Username: Skslvnv
Post Number: 44
Registered: Mar-06
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| Posted on Wednesday, April 11, 2007 - 11:37 am: |
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The VS50501 is a VZ4 chassis and uses completely different convergence amp IC's than the V17-18 chasis. Most of the info you find in this particular forum does not apply to your situation because the circuits and designs are completely different. I don't have the VZ4 service information readily available, so I can't tell you for sure which IC's your set uses. Technically this symptom is called "no convergence correction". Your symptom indicates a complete loss of convergence correction for all three colors. This could indicate a much more serious failure than just replacing the IC's. Sorry, but I can't be of much help in this situation except to say it does not use STK392-570 IC's. |
New member Username: Drsims2
Orangevale,
CA
USA
Post Number: 1
Registered: Apr-07
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| Posted on Wednesday, April 11, 2007 - 05:08 pm: |
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I'm new to the forum and very interested in repairing my mitsubishi ws 55807 with bow tie problems.
I build computers for my families and have soldered & repaired some motherboards(but never a tv)any and all help would be appreciated.IC part # and location on board |
New member Username: Pyrex
Post Number: 3
Registered: Apr-07
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| Posted on Monday, April 23, 2007 - 08:12 pm: |
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Alright ladies and gents... I'm tossing the towel in and |
Closed: New threads not accepted on this page