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[email protected] jurb6006@gmail.com is offline
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Default Sony TV KV2167MT picture has got curved

First of all, this is SCI.ELECTRONICS.REPAIR, not SCI/ELECTRONICS.BUYANEWONE. If someone wants to buy a new one, they are not here.

Now that that's out of the way, alot of Sonys have this coil, that due to its construxtion, fails. I believe it has a magnet in it and is a saturable reactor that is used for horizontal linearity correcti90n. At least it is in alot of them.

AStarting with the FSTs, when they became 20 and 27 inch rather than 19 and 26. Many many of them had such a coil especially up into the 1990s. Seems like they tried not to use them because of the obvious cost, and the fear of them failing under warranty.

This coil has a cor that has a specific level, and even curve at which it gets to magnetic saturation, and the magnet's strength is calibrated. Too much heat, gone. Also, these things tend to fail on the shorted direction but they really do not short. I think in most cases the coresa get sort of pulverized and lose there ability to be a good core for an inductor. Then the coil is running into air, and because the circuit uses feedback like the more modern vertical circuit, it is not noticable to the used until it pulls so much current that is ablows the pincushion modulator, which is what straightens the sidess of your raster.

The working of this circuit, in the larger deflection angles that came later, with the use of this system, actually caused a bent so bad that a vertical line owuld be bnowed, so they added parameters to the chip for bow which applies a parabola at the vertical rate to the horizintal AFC feedback loop. Some sets even had to have a separate correction for one side only because they could not work out all the nonlinearity.

Reactive scanning was a real bitch in heat when it came to totally flat screens like at 40 inches and ****. All that weight is not just the tube, some is what it takes to drive the ****er.

Also, I have some Sony OEM parts but I really doubt I have what you need. In the whole lot I only have a few coils.

OH ! In those sets, don't run them like that. When you get that problem the horizontal is liable to fry because it ain't right. Peak currnts too high, or voltage. ALSO, get a cap checker and check every cap off the, ;no, offf ANY terminals of the horizontal output. These are critical, and can also cause the failure of the pincusion output as well.

I don't know what you know right now, but htink of this as a CB radio final.. Look it up if you ain't familiar./ ANY fault in the circuitry there will cause a high SWR and make things fry. It is all a matter of timing. Something does not have to be shorted to fry the thing. It is not an audioo amp.

So I say at least do not run it.

And if you don't know how and wanbt to fix it, well you are in for an education. It ain't so bad.

And anther thing, in SOME cases a bad lytic can cause this. You havee to lookk at it, look for signes of overheating, bulging caps, all that.

**** buying a new one. That's what you did last time. not SCI.ELECTRONICS.LANDFILL.