Problems with the family TV

[TehJefe]

Im having a wide variety of problems with an old magnavox that Ive been using in my living room for aat leasta gooddecade and a half. Its not an arcade monitor and its not going in an arcade machine, but theres some valuable expertise on this board, Id say.
So, how to begin... I guess the first symptoms I noticed would be a good starter.
At first the TV was having a problem with jumpy picture.  It would jump so bad that I would get a double picture, infact. Duplicates of text on the satellite menus made it easy to measure, Id say about a whole half inch of jump. It seemed like this problem was aggravated by pictures with a lot of yellow or white in them.
After that came a really bad warping of the picture, starting in the upper left and warping the picture almost to the middle of the screen. Again this seemed to be made worse by scenes with lots of yellow, but that could just be my imagination.
After putting up with the distortion for a while (it was rarer and less annoying than the jumping, so I dealt okay) came the scariest symptom yet: the TV would randomly turn itself off for about 2-5 seconds at a time, and then turn back on. When it started doing this, I was ready to call it quits. Afterall, a decade and a half is a good amount of entertainment to get out of about 500 dollars. But now the TV is watchable again. It is currently having the warping problem again.
I dint know what I should do. Probably get a new TV... but money is really tight right now... so I guess live without a TV.
Due to the nature of the disappearing symptoms, I cant produce any pictures, but I could probably give a more detailed description if you think anyone thinks they can help me out. Even by just identifying whats wrong with the TV.. at least satiate my curiosity. 

[grantspain]

with a t.v of that age i would expect problems with electrolitic caps and bad solder joints mainly around the flyback transformer and any connector sockets(plugs)
only one concern would be if the flyback transformer itself was on the way out,sometimes when they split they arc to the chassis causing picture jumps-but certainly its worth looking at because if it is just caps and bad solder joints it won't cost much maybe a few dollars for the caps and a bit of your time.

[Kevin Mullins]

As mostly mentioned already:
Defineately look for any obvious bad solder joints around pins, headers, flyback, etc.
Most likely a failing capacitor problem which is common for the age and use.
Hardest part will be pin-pointing which ones to change. A general TV tech will have an ESR meter and check for anything out of tolerance. So you probably won't have one of those available. (I don't) The majority of the cost for a tech to do it will be labor, service call, etc, ... not parts. Problem being you won't find a capacitor "kit" for a TV, so your best bet would be to open it up and make a list of all the electrolytic caps you can find inside and just order them to make your own "kit".
The last repair job my mother had done on her old console TV cost around $175....turns out it was only a .70 cent capacitor that caused all her problems. (and it was jittery and fuzzy, etc)

Hope that gives ya some insight on it anyways.

[TehJefe]

Yeah, that definately gives me something to work with. Thanks a lot fellas. If it gets repaired, Ill have to do it myself... no way Im paying someone 170 dollars for a 1 dollar problem.  Im a little scared to decase the beast, but a little fear is a good thing. Itll keep me on my toes.
Once again, thanks for the replies.

[StephenH]

You might see if anyone has a schematic for it, and then note the cap values and try changing them.  It might also be a good idea to see if any resistors have drifted value, and if you get a schematic compare voltages to what the schematic says they should be, if they are listed.

Use care when discharging a TV, if you decide to separate the CRT from the board or change the flyback, as they do store thousands of volts!   The same safety practices that apply to monitors apply to TVs. 

[tta583]

What ever you do don't plug it in try and dork with it if the case is open.  IE, don't adjust anything..don't even think about touching anything.  You need to provide it power through an isolation transformer just like you would power an arcade monitor.  In short the metal frame is "hot".  Its part of the power circuit.  If you touch it you can become the path back to ground (Earth) between the TV and the power company.


With an ISO in line the power is between the secondary coil of the IOS and the TV.  There is no potential to ground between the TV and the Earth.  You are safe...unless you are touching the neutral side of the ISO's secondary.  Pretty much the best reason I can think of not to lick an ISO...if that is you sort of thing that is.

[ChadTower]

If you touch it you can become the path back to ground (Earth) between the TV and the power company.

House panel circuit breaker.  Not power company.  Unless maybe his TV is fifty feet high.