Convergence problems on HD Sony 36in (1 Viewer)

[Chris Tedesco]

I have the 36 inch CRT HD(KV36XBR800) Sony Wega set and have had a problem in the upper left hand corner, discoloration problem. So the Tweeter tech came to my house with his De-gaussing tool (sp?)

He ran it a few times with no sucess and thought right away that the picture tube needed to be replaced. As he tried to set up the time to pick my TV up, his boss said that all it needed was little magnets. (The tech had no idea what his boss was talking about)

Anyways, after the Tweeter tech ordered the magnets and left, I noticed that my T.V. image was no longer symmetrical. It seems slightly distorted near the bottom. ( I hear this is called Bowing or pin cushion)

Can running that Tech wand too much screw up my TV?

Personally I don't think the Tweeter guy was certified to be doing what he was doing.

Just trying to gather some information before I talk to Tweeter tomorrow.

 

[ChrisWiggles]

It sounds like an average joe tech who doesn't really know what he's doing. I would try to find a better service tech at tweeter if possible, or get the set replaced.

If he doesn't know about convergence/magnets and such, then I don't know if I'd let the guy get too far into the set unless you know you can get it replaced completely if (when) he screws it up.

 

[Chris Tedesco]

Yeah, the "Tech Guy" had no idea what magnets were. It was actually pretty scary.

So I called the Service manager today and he told me abruptly he would call me back. Did he? Not yet and I'm starting to get frustrated.

There is definately something not right with the picture. Not only geometry issues, but in widescreen where the black bars meet the picture, there is some misalignment.

I'm going to call Tweeter tomorrow where I bought it and see what I can get accomplished there.

 

[Gary Seven]

You should not use an external degausser on those Sony Wega TVs! I have the same problem but in the lower left corner. The discoloration is very small (~ 1/2 inch) and is visible on some backgrouns when in full screen mode. The tech tried with magnets and no luck. So I live with it. Greg came down and calibrated it so except for that discoloration, the PQ is excellent.

The tech not knowing about the magnets is indeed scary. I would try to get a more experienced tech.

For a sight dedicated to Sony products and their problems, I suggest http://www.agoraquest.com/

 

[Chris Tedesco]

Thanks guys, this really helps! I have called the Tweeter Tech Service and let them know I don't want that same guy coming out. I let them know that I found it very hard to believe that he was certified.

Anyways, I let them know about the existing problem as well as the new one and they apologized. They are going to be coming out next week to see if they can fix it. They better not bring the external degausser this time. That thing caused a mess.

 

[Jack Briggs]

Instead of calling Tweeter, you should have called Sony's service center directly.

Any "tech" who suggests placing magnets anywhere near a CRT is unqualified to be a tech. TV "sevice" or "repair" shops are ripoffs.

Here is a case — certainly with a display as sophisticated as a Sony WEGA — where the investment justifies the services of an ISF-certified calibrationist.

 

[ChrisWiggles]

Not so. Magnets are used often in CRT devices, and can be used to correct convergence problems, beam focus, etc. Very advanced CRTs can have electronic coils that function as variable magnetic correction to the beam for astig issues as it scans, etc etc.

Good techs who really know their stuff aren't usually the guys who work the chain stores as "service" techs, but there are good shops out there with people who know what they are doing, you just have to hunt around for them.

 

[Steve Berger]

Sony uses two types of correction magnets along with controls on the neck of the tube. A spot magnet which sticks on and can rotate to tweak and a plastic strip with a small magnet that slides under the yoke. Unless the set had the problem from the beginning , using magnets is generally useless. No human can match the robot that did the initial setup. The setup on the very large CRTs is so sophisticated that it has a regional aspect. (a California set shouldn't go to Colorado) A strange shielded cage is suppossed to be used for purity setup. (no servicer I know of has one)

You may truly need a new picture tube now after the attempt to degauss it with a wand (depends on which one he used). During manufacture a special robot magnetizes spots on the shadow mask to correct marginal CRT problems. It cannot be duplicated in the field. If the spot magnetization is removed (coil , storm , vacuum cleaner , any large electromagnet , etc) then purity will never be perfect again. Replacement tubes are much higher quality that the originals. We throw all the old magnets away and set controls to zero and do minor tweaking when a CRT gets replaced. (the replacement has to be good enough for broadcast monitors since it is the same part number) Sony has a low power wand (not coil) for manual degaussing. Freezing the thermistor is used to lenghten the degauss cycle on some models. Moving the set away from potential outside magnetic influences is the first thing done , of course. Ever see a what magnetized cold air duct or ground strike by lightning can do? If the simple things don't fix it then replacement is usually called for ; further tweaking is usually a waste of time and money.

The service tech (in this case) may have more experience with this problem than the man in the office (who may not understand all the differences between brands) He may be an accountant type rather than a tech type , or an old time tech who hasn't kept up. Authorized Independent Servicers must attend training and have specific equipment. Servicing dealers (who are not necessarily bad) have NO such requirements. They can use the lever of "If you don't let me service your set then I won't sell them" arguement to bypass important qualifications. Good dealers will train their people but they don't have to and the best tech can get fired for political or economic reasons leaving a decimated service department because the "bean counters" are in control of service right now in large companies.
edit: The banding issue was very poorly documented (and late) in official service bulletins. CRC (customer respose center) was giving out verbal info months before they hid a fix in service bulletins - which you couldn't find unless you read every single bulletin on the web-site -- no mailings any more) That's why I started reading forums - to keep up with the industry - servicers are on the bottom of the industry pecking order.

 

[Jack Briggs]

Sorry, I was being unclear. I took it that the tech in question advised using magnets — like refigerator message-note magnets — strategically on the cabinet the way weights are used on wheel rims when being balanced. That's what I meant. But thanks, Chris, for pointing out my misleading post!