Expert: Rick Montgomery - 10/10/2009

Question
QUESTION: I am disabled, and starting to go blind I was given an abused Philips 55pw9363/17f that was working, until they tried to replace the ic chips, then nothing. I looked at the solder job, and the board, then decided to get a ssm from partstore as the old one was toast. I replaced the 3d comb filter they lost. got a new power input board they lost, and have the following problem. Not sure of wires are in right place but the set starts begins to warm up the crts come on, I get a rainbow on the screen, then set goes off. clicks, and restarts, will repeat this until it is unplugged. An ideas appreciated as cant afford a lot to fix this thing,

ANSWER: Charles,
  Without the possibility of being there to check the previous work, all I can provide you with is a generic answer. The one clue you provide is the "rainbow". To me a rainbow suggest a certain picture, but it may be just a difference in our terminology. You sound as if you have some technical ability, so I'll give you my one thought. If your symptom BEFORE shutdown is more like a double or triple image, you have a convergence problem. As you know, there are 3 picture tubes in the bottom of your set, one for each of the primary colors of light, red, green, and blue. They each contribute their color portion of the complete picture. There is a circuit known as the convergence drive amplifier, that causes these three images to align, or CONVERGE into the one complete image you see. The primary components are the STK drive IC's. You should be able to buy generic IC's for around $15 to $20 each. There will be 2 in your set, replace them as a pair. Also pay CLOSE ATTENTION to the low value flameproof resistors and any fuses in the circuit. A shorted drive IC can cause shutdown.
  Without my being able to see what was done so far, I cannot advise you beyond that.
regards,
Rick

---------- FOLLOW-UP ----------

QUESTION: Thanks Rick apporeciate the anser, the i/c are the convergence on the ssm correct? Those are new, got the entire board from partstore.com, the previous person cooked it and the traces were loose so didnt even mess with it. The rainbow is just on the bottom of the screen, what gets me is I cant get it to stay on long enough to check anything, Is it possable they have the wires on it wrong, or a cable is missing. From reading the maual, the set soft starts , the crts light , then the set goes to high, the crts, get bright. So far that works, then the set resets, and does it all again,I know they moved it several times, I am going to check the solder connections on the LSB. I think, and could be wrong, either the crt is out of coolant,leaked on the lsb, or I have powersupply or flyback issue. Can you tell me where I can get a picture, not shcematic of the proper cable routings? Thanks again

ANSWER: Charles,
  Personally, I don't believe that you have a horizontal drive or flyback problem. I could be wrong, but it doe not seem probable. You tell me the CRT's light, and brightly. Well, as you know, in a projection TV they HAVE TO light bright, far more so than in a direct view TV. That brightness has to be distributed over a much larger area. One more possibility is that the screen voltage is set too high. Try turning it down some and see if the set remains on.
We have used Partstore.com, and have had no problems with their parts that I recall, but there could always be an exception in there somewhere. You still did not elaborate on my suggestion that your "rainbow" is a convergence issue, or general discolorization.
As for your request for a picture, there I can't advise you. I have access only to the Philips Service manuals, and the Allexperts rules prohibit me from sending copyrighted material, such as service manuals. I have not had one of these models in my Service Center in a long time. That would be the only other source of a picture. I would see if there are any labels on your deflection yoke plugs, and make sure they are inserted into the correct sockets. Inverting them might account for your rainbow effect, but it seems to me that it would affect the top too.
Rick

---------- FOLLOW-UP ----------

QUESTION: Ok lower the voltage and brightness of the crt's and now it stays on for about 1 minute, full screen nice and bright, show's a picture, about the time I go ti the menu to adjust the convergence it shuts down and starts over. Getting closer

Answer
OK, if it's "nice and bright", I still can't see it, but if it is staying on for a minute, the screen voltage may still be a little too high. Try turning it down a bit more and see what happens. You can't hurt anything with too low of a screen voltage like you can with too high. You just won't have as bright of a picture. See if you can find a point where the set continues to run. I wouldn't want both of us digging for something hard, until we check all the easy stuff first.
Rick