Phillips 50p8341a, Convergence Problem..

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Phillips 50p8341a, Convergence Problem..

TV has the redish glow thing going on that I keep reading about.  I'm unable to adjust the blue convergence.  Where are the Convergence IC's located on the board, and which STK do I purchase?

Thanks is advance..

Wait a minuite! Reddish glow

Wait a minuite! Reddish glow ? that is not a symptom of convergence failure.  you will see a red distinct immage not overlayed correctly with the green and or blue immage on the screen. What you are describing sounds like fluid issues, but the red tube never has fluid problems in philips, you usaly will have a blue or green halo, the red will be sharp. BUT!! the picture will turn reddish, because of the lack of blue and green. Turn on your set and put it on a good channel, look down into each picture tube and see if it look cloudy, look in the red first so you can see what a good fluid looks like, then look down into the green and blue. if it looks cloudy and not absolutly crystal clear, you need a fluid change.

Sorry about my lack of

Sorry about my lack of quality description.  The picture actually did turn reddish because of a lack of blue.  I can adjust the Red convergence, but the blue doesn't seem to move at all. 

I did as you said and looked down into each tube, and the fluids seemed to be the same.

I'll try to upload a picture since I seem to suck at a good description.

(No subject)

I tried to post some more,

I tried to post some more, but those were the best pictures I could get..

You need a fluid change, your

You need a fluid change, your stk's are fine. - i am doing a fluid change today actualy.

Larry Dillon
Good Luck dude! I did two in

Good Luck dude! I did two in the past month!

i can do these blindfolded :)

i can do these blindfolded :), we used to only sell philips tv's back in the early days, so we get allot of them, but we hardly sell any phillips anymore, we sell mostly sony and pioneer.

Hey, you might want to point him to your fluid change post! i am not sure where it is.

zapdbf said: You need a fluid

zapdbf said: You need a fluid change, your stk's are fine. - i am doing a fluid change today actualy.

Ok, thanks a million for the info..  Is a fluid change something I can do, or does it require me to pay an arm and a leg to a repair man??

Larry Dillon
If your handy, you can do it.

If your handy, you can do it. No problem. If your not, play it safe and call in a pro to do this for you.

Changing Projection TV Coolant 

 1. Tip the TV set so the expansion chambers are pointed up. The expansion chamber is a small white/clear plastic bulb-like thing That is attached to one side of each of the CRT's up near the top lens. In some TVs, the expansion chambers are already pointed up - In this case you don't have to tip the TV 

2. Cover the circuit boards below the CRT's with several paper towels to prevent accidentally spilling any coolant onto the boards. The coolant is corrosive and will destroy the circuit boards. Don't skimp on the paper towels here - they are cheap!!! 

3. Remove the four screws that hold on the focusing lens assembly and remove the focusing lens assembly. 

4. Note the position of the expansion chamber then remove the expansion chamber. It will need to be reinstalled in basically the same position so remember the position or take a picture if you need to. There is a small o-ring on the neck of the expansion chamber where it threads onto the CRT housing - Don't loose it!

 5. Use the baster  and tube to suck the fluid out from the hole where the expansion chamber was removed. This hole is fairly small...maybe 5/16" or so. 

6. Once most of the fluid is out, remove the four screws that hold on the lens cover plate. 

7. Remove the lens cover plate, the lens & the large o-ring. (be gentle with the o-rings!!!) 

8. Clean the CRT chamber & lens with denatured alcohol. Use 100% cotton balls so you don't scratch anything.

 9. Clean the CRT chamber and lens with distilled water. Again, use 100% cotton balls so you don't scratch anything. This will rinse out the alcohol residue. You need to use distilled water for this so there is no mineral residue. 

10. Gently clean the large o-ring with distilled water (don't use the alcohol because it might eat the o-ring) Dry off the o-ring and lightly coat it with 100% pure silicone (not siliconized acrylic caulking or acrylic latex caulking - ONLY USE 100% SILICONE). Use your fingers to rub a thin layer of silicone all over the surface of the o-ring. Then place the o-ring in the groove in the CRT housing. 

11. Place the lens in its position on the o-ring. 

12. Place the lens cover plate over the lens and install the four screws. 

13. Clean your baster and tubing with denatured alcohol then rinse with distilled water. 

14. Use the baster and tube to suck clean fluid from the bottle and install it into the CRT through the expansion chamber hole. Go really slow when it is almost full to minimize overflow. Wipe up any overflow immediately. There will be a small air pocket in the CRT when you are done - you will not be able to fill the chamber 100% - This is O.K. Just be sure to fill it as far as possible so the fluid is just up to the edge of  the expansion chamber hole. 

15. Install the expansion chamber. Be sure to install it in the same position as it was before you removed it. Also be sure that the small o-ring is on the neck of the chamber before you thread it on. The chamber is just plastic so don't over-tighten it or you might damage it. Screw it on as tight as you can go by hand and then give it about 1/8 of a turn with pliers. (you might have to use needle-nose pliers to get a good grip on it.) 

16. Place the focusing lens assembly into position and install the four screws. 

17. Turn on the TV and check for leaks over the next 20 minutes. Remember, you have not yet removed all the paper towels from inside the TV. Remove these once you know there are no leaks. Other things that should be done after replacing the fluid include... 

1. Clean the mirror

2. Clean the top lenses of the focusing assemblies

3. Focus the CRT's

4. Adjust the convergence 

Here is a list of things you will need: 

1. Turkey baster

2. Vinyl tube

3. Cooling Fluid

4. 100% cotton balls

5. Paper towels

6. Denatured alcohol

7. Distilled water

8. Pliers

9. Screw driver 

Ordering Coolant: MCM Part #: 20-4275At    

lol @ Larry, cuz I had just

lol @ Larry, cuz I had just found that post, and was already reading through the details..  MUCH appreciated..  I already had the set ready for some new IC's (figured since I had already bought 'em, I'd go ahead and replace 'em) then I'll follow your steps for the fluid change..

Wish me luck!!

Josh Carter
This same model of TV was

This same model of TV was just given to me and has a similar problem except i notice the whites on the screen are always extremely bright and the darker images seem too dark. Is this also a coolant problem, or something different?

Did chaging the fluid fix the

Did chaging the fluid fix the problem for the tv that was having all the porblems?

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