Tip & How-To about Televison & Video

How to repair projection TV (fades in and out)



This thing you have do:

  1. Open the cover of your TV.
  2. Look at the CRT driver board inside and remove all screws including the cover of that board.
  3. Then rotate the CRT board in reverse position to apply a voltage data.
  4. Power on the TV to start a voltage data.Use a multimeter (range on DC) then place your black prob(-) to the ground of the TV and the other one is place on the B+ that usually found on the 3rd pin of the ply-back transformer.Check the B+ voltage if you have a 100-120vdc.
  5. I'm sure you have the B+ voltage because your TV is not totally dead.Check the reading of the B+ if it is flickering.
  6. If the B+ voltage is flickering and you hear a clicking sound,try to hang the connection of the B+ to the fly-back then look at the reading if still flickered or stable.If the reading is stable when the B+ connection is hang.You have to replace the ply-back because it is shorted.
  7. And finally after you replace the ply-back.Power it ON.
Thank you for reading my tips.

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Our tv keeps changing colours to blue red and green

Your television have color problem.That symptom is cause of loose connection or cold solder in chroma section and color output driver transistor of CRT board of your television.You can fix that problem by resoldering the chroma section and crt socket section of your TV.first thing to do is open or remove the back cover of your TV,then you can see the crt board connected to picture tube.Resolder that parts,specially the color output transistor the red,green and blue driver.Resolder also the chroma section.You can see the jungle ic,thats the color ic.Make sure that there's no short circuit when soldering the PCB board.After the resoldering turn on the TV and check if color is normal.Thanks..
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Yellowish green area in middle of picture

you need a degaussing tool. it was most likely magnetized. make sure you move away magnetic things as well as unshielded devices such as unshielded speakers and other powered devices. this is what will cause the problem.
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9p5511c102 the picture fades in and out ? can it be fixed ?

Good day!

Your TV is a CRT?

This thing you have do:

  1. Open the cover of your TV.
  2. Look at the CRT driver board inside and remove all screws including the cover of that board.
  3. Then rotate the CRT board in reverse position to apply a voltage data.
  4. Power on the TV to start a voltage data.Use a multimeter (range on DC) then place your black prob(-) to the ground of the TV and the other one is place on the B+ that usually found on the 3rd pin of the ply-back transformer.Check the B+ voltage if you have a 100-120vdc.
  5. I'm sure you have the B+ voltage because your TV is not totally dead.Check the reading of the B+ if it is flickering.
  6. If the B+ voltage is flickering and you hear a clicking sound,try to hang the connection of the B+ to the fly-back then look at the reading if still flickered or stable.If the reading is stable when the B+ connection is hang.You have to replace the ply-back because it is shorted.
  7. And finally after you replace the ply-back.Power it ON.
NOTE: If you don't have any basic knowledge about electronics and proper usage of the electronic repair kit such as multimeter,soldering iron and screw driver.Please don't attempt repair it on your own because it causes major damaged to the unit.


I hope this solution will be much helpful.Thank you and good luck.
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a spider is on the inside of the screen. how do I open the tv open to get the spider out and clean the inside of screen and lenses?

go_n,
First gather your needed items: screwdriver and a helper.

The screen is mounted to the enclosure of the TV by hanging on tabs mounted on the enclosure inside behind the screen. The screen simply lifts off after removing it's set screws at the bottom of the screen behind the big plastic piece that is below the entire screen.

1) Remove the speaker covers (grills).
2) Locate and remove the screws that hold the plastic piece onto the enclosure (8-12).
3) Remove the plastic cover and you will see the set screws holding the screen.
4) Remove the screws (2-4).
5) Use your helper as your screen is really big for most average sized people and lift the screen including the plastic bezel up and away from the enclosure.

Ensure that you have a secure area to set the screen as it will be large, heavy but yet very delicate. Also, do not clean anything unless you know for sure that you need to as sometimes just by touching things they get misaligned or break. This means but is not limited to: mirror, lenses & the screen.

When reinstalling the screen ensure that you hang the screen back onto all of the tabs or the picture will be blurry.

Good Luck!

-Chris
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Procedure for replacing fluid in our rear projection television

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.
Or if you find this difficult remove all 3 CRT tubes from the metal cradle they are screwed to & lift each tube completely out you will need to unplug & disconect all leads from the crt.
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 the exact
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
Ensure you use only the coolant made specificaly for projection CRTs

http://dysonmanuals.llc.nu/

Chris..
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