Model - Bush 2137T 21"
The problem has been deteriorating gradually and now the TV screen is only displaying a horizontal 1" picture. The sound is still ok and the channels are still working. Any comments please. Thank you in advance.
An expert who has achieved level 3 by getting 1000 points
An expert that got 20 achievements.
An expert that got 10 achievements.
An expert that got 5 achievements.
Re: TV screen dislay partial horizontal beam
This is a problem with the vertical circuit. Look for a small flat IC attached to a heatsink that will be marked LA7837 or something similar. It should have about 11 pins. Try resoldering the pins on that IC first. If that does not resolve the problem, replace the IC. There may be capacitors that require replacement in that circuit as well.
- 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.
Check and replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. http://electronicshelponline.blogspot.com/
First, You should to replace by original part, then you should check the voltages on power supply, and check the voltage for vertical IC based on datasheet, also check the voltages on vertical section including yoke and last you should check the ESR capacitors on vertical section.
Power light is there, and sound is OK, indicates the faut is with the horizontal output section. Check all the components in the horizontal output circuit. Line output transormer should be suspected. Image of the suspected components attached.
Funnily enough I have been given a 21 inch standard Bush set with the same problem!
It's a DEGAUSSING fault. This means the deguss circuit in the TV is not operating as it should - probably a faulty positor. When you switch the TV on (NOT FROM STANDBY) the circuit that removes magnetism from the screen does not work correctly.
Switch it off, unplug the set from the mains for 30 minutes or so and try it again. If there is no change, contact a TV repair centre.
Make sure there are no hifi loudspeakers next to the TV or a radiator as this can have an effect too.
Most likely it has a horizontal width control on the inside of the set on the main module. It is usually to the right side of the set near the high voltage transformer. I advise caution unless you understand the operation of the tv and the components near the control.