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Re: bad solder connections on the vertical ic
Cold solder is normally fix with re-application of heat using a soldering iron. This is a fairly straight forward job and should not be that difficult. Probably what would take more time is opening the back cover and exposing the solder side of the PCB. Most TV PCBs are slide in/out (it may held in place by screws or retaining clips or side locks. Additionally, some of the wires/connectors may restrict movement and therefore must be disconnected temporarily).
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You have bad grounds on your vertical IC. And you have a bad capacitor or two. I don't recall the actual location of the vertical IC location. I would say it may be U4501 location. Resolder the seven pins of this IC. Now check capacitor locations C4505 which is a 35 volt 220 Mf value, and C4506 which is a 63 volt 330 Mf value.Replace these caps as necessary. Then check the solder grounds at the power supply chip U4101, this chip is a switch mode regulator and may become detached from the board. Resolder these 11 pins and be careful not to short the pins with too much solder. Please note the two pins on the right (separated by a missing pin) are soldered together, this is OK. Now for the biggest challenge. You must pull the bottom shield off the tuner (has the RF connection). Yes, this area can produce the horizontal lines you speak of. When removed, you will see about 15 bad solder connections. This area will require great skill to resolder. The solder on the perimeter of this tuner is very difficult to work with, and you do not want to burn off any traces connecting to out side feeds. You could destroy this board. Now inside the tuner area there will be 5 pins or grounds that will need resoldered. Be careful here and not to burn off the small traces leading to other connections. Replace the tuner shield after complete inspection and soldering. In some cases the eeprom, locationU3201, will need replaced. Might not in your case as you say you can still watch TV and the audio is good. I know this is a lot of information, but this TV can be saved. I have repaired many of these. Thanks for asking and show a few hands of support.
If you can take the board out of this TV, you will find many bad solder grounds. First places to look for, are the vertical IC and the horizontal transformer. Be sure to check the solder connections on the small board connected to the picture tube. Very common problem for any and all these tube type TVs. If the vertical IC has bad grounds it would be in your best interest to replace the capacitors near and next to this IC. In any case resolder any and all bad solder connections. Your picture will return in most cases. Thanks for asking and show a few hands of support.
you either have a bad vertical ic or just bad solder connection around the vertical ic and stage. When the TV is fine, if you slightly tap the set and the problem presents itself, then it is bad solder at the ic and stage.
Sounds like you may have a bad solder connection on the vertical ic, it is a small ic connected to a heat sink near the flyback. Usually a 5 pin ic, look on the solder side of the board for a solder connection with what looks like a ring around the pin.
Bad vertical deflection circuit, unless you have a bad connection (bang on set to set it it fills out for a second) . you will need components replaced such as the IC, capacitors possibly a fuse from the power source to the vertical IC.
If its a bad connection soldering the IC pins is not to hard if you are OK with taking it apart yourself.
If the line of which you speak is a horizontal line that looks like the picture collapsed, the problem is a vertical circuit problem. If hitting the set "fixes" it, then it is likely to be a bad solder connection. If you can solder, resolder the pins on the vertical IC. This is a small flat IC with about 11pins attached to a heat sink that may me marked LA7837 or something similar.
This is a fault in the vertical circuit. It can be either a bad solder connection of the vertical IC or a defective IC. If you can solder, you can fix this yourself. Open up the back and locate teh vertical IC. It willbe a small flat IC attached to a heat sink and be marked LA7841. Resolder the pins first. If that fails to resolve the problem, replace the IC. Please note that there may be capacitors in the circuit that need to be changes as well, but without the chip working, it will be difficult to determine which ones. Update this once the IC has been resoldered or replaced with the results and we'll continue if necessary.
If you have intermittent line horizontally across both tv screens then there is likely to be bad solder connections on the vertical ic's of both of them. This can be fixed by taking the back off with quarter inch nut driver and carefully sliding the chassis out and turning it up to see the solder side. I don't know the location numbers but the vertical ic will be mounted on a metal heat sink and the connections will be in a row. Sometimes you can see the bad connections. You may need a magnifying glass. I recommend someone who has experience soldering electronic circuits. No solder bridges etc. This is for intermittent (works sometimes) problem on vertical ic. If the line stays then the chip ic is bad along with a 1 ohm resistor off the flyback high voltage transformer. From what you described you likely have bad connections. Hope this helps