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Widescreen 28"+ Crt's, Service Menu Convergence and Geometry?

post #1 of 9
Thread Starter 
It seems like a lot of the widescreen Crt's have issues with convergence over time.
I am looking into getting one and I would like to avoid making any (possibly dangerous) mechanical adjustments to dial in convergence and or Geometry.

Does such a tv exist or are simple user and service menu convergence and geometry setup limited to rear projection Crts?
post #2 of 9
Quote:
Originally Posted by Mik James View Post

It seems like a lot of the widescreen Crt's have issues with convergence over time.
Simply rotating a CRT can affect its alignment/convergence due to the earth's magnetic field.
Quote:
I am looking into getting one and I would like to avoid making any (possibly dangerous) mechanical adjustments to dial in convergence and or Geometry.

Does such a tv exist or are simple user and service menu convergence and geometry setup limited to rear projection Crts?
Most CRT displays made post-2000 have electronic controls for alignment and convergence. The mechanical adjustments are typically only for initial setup.

Regards
post #3 of 9
It's usually easier to correct geometry issues, than to correct convergence issues. Frequently convergence can only be corrected by way of ferrite or magnetic strips along the tube, can be a real tough nut to crack just the right way. In the western world, where any CRT you find to buy will surely be second-hand, the best advice is to ask to view the unit before purchasing. If you want it for a specific purpose, be it DVD playback, Bluray, gaming or whatever, bring your equipment. The worst any seller can say is "no," and they won't likely say that either as they want to unload it. Just make sure you can take a look at it working to see how it is before buying, and you will be as reasonably safe with your new tube as you can be. And once you have a well-working tube, if you don't subject it to a lot of abuse, it should remain so for a good long while.
post #4 of 9
Thread Starter 
So how bad does convergence need to be before you need to adjust it with magnets rather than menu adjustments?

I'll probably just post some sets on here that i'm looking at buying. I really don't want anything that doesn't have menu convergence adjustment.

Is the Panasonic CT 34WX54 any good?
The higher the resolution the better. It sounds like the Sony Sfp tubes have the highest resolution but how do the other brands stack up to the 1400 lines of the top Sony's?
Edited by Mik James - 7/24/13 at 3:41pm
post #5 of 9
I really like my Panny WX50 other than I would like it to be more modern (DVI or HDMI and ATSC tuner); superb sound for a TV too with 5 speakers and an acoustical waveguide system built into the cabinet. I had comm'ed with a WX54 owner on one of these threads and he loved it. I always wondered if that higher res would really matter on a 34" TV unless one was sitting [too?] close?
post #6 of 9
Love my CT-34WX54, yes indeed. Given to me for free by a nice gentleman on craigslist. That was, what, 2 or 3 years ago now? Still going strong.

I watch it more than any other TV in the house, and I have a 46" Sony LCD and 50" Samsung plasma available. Now, being in the bedroom is probably the main reason for that, but still, if it looked like crap I would move one of the other sets in there. It does have some curvature when watching 2.35 : 1 movies, but unless I'm focusing on it I don't really notice it.

I'm sure if I knew how to adjust it properly it would look even better, but I'm happy.

I have two more free craigslist HD CRT sets waiting in the wings; I figure I won't be buying any televisions for decades. smile.gif

Oh yes, and Floydage is dead-on regarding the sound. My CRT Panny will kick the living snot out of any flat panel TV in that regard.
post #7 of 9
Deja vu it was you 'Loaf! It's all coming back to me now.

I wonder how those Sony 960 and the like stack up against the Pannys for sound as I've never heard one.
post #8 of 9
Quote:
Originally Posted by Mik James View Post

So how bad does convergence need to be before you need to adjust it with magnets rather than menu adjustments?
Rather than guess, I look a look at the Sony service manual for my XBR910.
The adjustments in blue are performed using the service menu

"The following adjustments should be made when a complete realignment is required or a new picture tube is installed.
. BEAM LANDING
. V-PIN AND V-CEN ADJUSTMENT
. . VERTICAL AND HORIZONTAL STATIC CONVERGENCE
. . OPERATION OF BMC (HEXAPOLE) MAGNET
. . TLH PLATE ADJUSTMENT
. . DYNAMIC CONVERGENCE ADJUSTMENTS (Only H-component can be corrected, for vertical component use permalloy to compensate)
. SCREEN-CORNER CONVERGENCE
. FOCUS ADJUSTMENT
. SCREEN (G2)
. PICTURE QUALITY ADJUSTMENTS
. WHITE BALANCE (CRT) AND SUB-BRIGHT ADJUSTMENT
. H RASTER CENTER ADJUSTMENT
. PICTURE DISTORTION ADJUSTMENTS"

The key item is that only horizontal convergence can be adjusted through the service menu (on these Sonys).
A vertical correction would have to be done using magnets.
I would expect a "calibration" to go through all of these adjustment steps.

I find it interesting that convergence is adjusted before distortion (i.e. geometry). On front projectors mechanical and static & dynamic electrical adjustments for geometry (aka alignment) are done first on the green CRT, then the red and blue are converged.

Regards
Edited by blue_z - 7/25/13 at 6:24pm
post #9 of 9
Thread Starter 
Well, I'll probably pick up a Sony or Panasonic.
Sounds like Sony wins for available adjustments and other brands like Panasonic, Samsung, Toshiba, Philips etc only have geometry adjustments?
Any other traits of the various brands I should know about?
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