I would like to remove crt tube myself but understand their is high voltage withen the set even when unplugged......I would like to know how to disable voltage in order to remove tube and it's components in order to send to company for replacement.If I am able to do this part myself it would save me quite abit in labour
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
If it is a CRT (old tube television), the most likely reason is there is a loose connection on the yoke at the back of the tube. I fixed mine with the addition of a tine (1 square mm) piece of foil added to the pin at the top - any bigger, and you risk shorting it - not good. A tiny bit of solder on the pin is probably the better option Be aware that opening up a CRT television is like swimming in croc infested waters. Even after being unplugged, they can still kill you. The pins you are dealing with are low voltage, but there is some serious high voltage stuff in a TV. It is best to get a technician to do it if you have not been taught about high voltage safety.
If this is a CRT-type rear-projection TV, the CRT coolant fluid is probably broken down. It's supposed to be clear, but after a long period of TV operation, it turns a yellow-brown color. If you unplug the TV and remove the back, you can look into the tops of the three picture tubes. They should be a clear red, green or blue color, with no yellow-brown tint.
CRT coolant can be changed, but you need to be very good at mechanical work to do it. Besides the safety considerations (picture tubes and other parts may carry a high voltage charge even when the set is unplugged), spilling broken-down coolant on electronics is usually disastrous, so you have to be very careful.
LCD panels used in projector applications may lose contrast if they are overheated (this can be caused by failure to keep the vents clean as recommended in the owner's manual).
You would have to provide your set's model number to get more specific information.
You have a high voltage leak, one of the three crt's are arching to the metal chassis, this will cause momentary high voltage loss so your picture will fade until the voltage builds back up again.
Repairing this is hazardous because the voltage in the crt's are around 30,000 volts even with the tv unplugged. I don't suggest doing this yourself.
A technician will do the following he will attempt to stop the leak with specially formulated silicone compounds, If this fails the only alternative is to replace the picture tube that is defective.
The cost of repair depends on if the tube will have to be replaced, the initial repair using silicone should not run more than the standard service call rate for the company servicing the unit. If it is picture tube the cost could be upwards of $400.00
Replacing a flyback is not something I would suggest for anyone with no electronics experience. Second, lets see where the noise is coming from first. Take off the back and listen to the noise. The flyback will be at one end of the large red wires that go to the tubes. Sometimes the connection at the tube is not 100% and the noise comes from there. BE CAREFUL - there are high voltages going through this red wire that can be dangerous even with the set UNPLUGGED!! IF the noise is coming from the connection at the tube, with the set unplugged, carefully turn the rubber cap back and forth touching only the rubber part with one hand. Put the other hand in you pocket while doing this.
If the noise comes from the flyback side, if you can solder, again with the set unplugged, try resoldering the pins on the transformers. That may resolve the problem.
yes they can hold a bit of voltage so a high voltage probe will discharge them nicely, something you might not have but can get from ebay if you are going to do this alot. you don't need to be concerned about this though as you won't be doing anything with them so don't touch..
just be carefull when desoldering these stk's use solder wick and patience even a pro can take an hour to desolder these so be carefull not to lift the trace or the situation will quickly get worse. don't adjust these tubes as they are set to the correct alignment already.
Sounds like the red CRT has an internal short. Sometimes happens that the picture tubes develop an internal short and cause arcing. I world CAREFULLY disconnect all of the wires to the CRT and see if the arcing goes away. VERY IMPORTANT!!! there is a high voltage wire attached to each pictur tube, usually a red wire that goes to the side of the tube. You can get a shock even if the TV is unplugged, as the tube will hold a charge for years after the power is disconnected. If you don't feel comfortable doing this, DON"T since the shock is powerful enough to stop your heart.
Check the info from this website on how to remove shorts from CRTs. This is not a DIY for sure.
The CRT you can remove it yourself, just be very careful when removing the high voltage wire that is connected from the HV trippler to the CRT anode. The CRT anode cable stays with the CRT.
TV's use high voltage to generate the stream of electrons traveling
across the picture tube hitting the screen and lighting it up (thus the
name Cathode Ray Tube). It takes about 25,000 volts to do
this. In normal air, it takes about 1000 volts to jump an inch of
air, so the high voltage transformer needs to have good
insulation. It generates the voltage through a technique of
charging the transformer's magnetic field with a low voltage of about
140 volts then letting it go where upon it flys back out the high
voltage side at much high levels (Thus the common name
flyback). A most common failure in a CRT type TV is for the
insulation to crack in this transformer which is a unique component for
each model of TV and leak out the current overstressing the circuit
driving it. You can liken it to a little bolt of lightning
getting loose in the circuit and has the same sound on a smaller scale.
It would be well to replace your flyback transformer before it gets
worse and blows up something else as well. Best done by a
professional used to handling high voltage. The picture tube can
retain voltage even when the TV is unplugged for some time, and
replacing the anode lead (the big red one) can be dangerous.
Hope Ya Fix It!