From: kucharsk@solbourne.com (William Kucharski)
Newsgroups: rec.video
Subject: Sony: Geometric Distortion and other tradeoffs...
Date: 28 Jan 1993 18:38:03 -0700
Organization: Solbourne Computer, Inc., Longmont, CO
Distribution: na
NNTP-Posting-Host: anthrax-fddi.solbourne.com

While reading article <1993Jan27.225730.1302@cmkrnl.com>, I noticed that
jeh@cmkrnl.com said the following:
 >There are adjustments in the "service menu" for pincushion distortion in
 >*vertical* lines (imagine the above illustration, NOT turned on its side), but
 >in horizontal lines it is corrected by moving these funny little permanent
 >magnets around on the back of the CRT.  Moving these magnets also affects
 >convergence.  The trouble with that tradeoff is that you'll notice convergence
 >errors all the time.  

Yes, yes!! I went through this same brain damage when I bought my 27XBR15.  I
went through two sets, up and down my apartment stairs, before realizing that
I should try them (three more!) out in the store first.

The two major problems:

    1) Out of five sets, the picture on four was rotated more than two or
       three degrees (e.g. the yoke wasn't quite straight).

    2) Out of five sets, all five experienced the distortion of horizontal
       lines at the corners of the screen.  I had an actual Sony factory
       service person work on it, but he never did get the lines straight
       (the best he got was sort of a __---__ in the corners where the "---"
       was where the magnet was) and the convergence was so horridly off that
       I exchanged that one for yet another new one.

       Finally, I just set up two or three in the store (a high-end audio/video
       dealer, that's why they were willing to put up with all this) and picked
       the "best" one.

       BTW, the horizontal curve definitely IS caused by varying magnetic
       fields, as they exhibited a slightly different amount of bend in place
       in my apartment than they did on my dealer's floor.

Other notes:

    1) I also looked at a Proton; it was skewed (rotated yoke) and also
       exhibited slight geometric distortion (though not as much as any
       of the XBRs).

    2) The Sony 25" XBR Pro Monitor (~$1500 for monitor ONLY) seemed to
       get it right, but it was only 25" and I wanted a 27" set.

    3) Ever since I became sensitized I haven't seen a major maker of large
       sets that hasn't exhibited the rotated yoke/picture or geometric
       distortion problems or both on sets I've seen on display.  This
       includes Proton, RCA ("normal" and "ProScan"), NAD, Mitsubishi and
       Panasonic (including the GA00 sets).

I talked to the Sony tech about this and he said that ALL monitors have this
problem, and perhaps that's true, as even the 19" Color Trinitron monitor
I'm currently viewing has some problems along these lines.  I eventually
went with the Sony anyway as it had the best picture, the features I wanted
(PIP and Channel Scan), and most importantly of all, Remote Service Mode so
I could adjust overscan myself.

Would I purchase another Sony?  Yes.  The picture is great, and, unfortunately,
none of the other television manufacturers I've seen have it right either.  And
none of the other brands have the Remote Service Mode so you don't either have
to wait around all day for the service tech (who usually knows less about your
set than you do) or muck with pots located (seemingly) a few millimeters from
the flyback.
-- 
| William Kucharski, Solbourne Computer, Inc.     | Opinions expressed herein
| Internet: kucharsk@solbourne.com   Ham: N0OKQ   | are MINE alone, NOT those
| Snail Mail: 1900 Pike Road, Longmont, CO  80501 | of Solbourne Computer, Inc.
| President, "Just the Ten of Us" Fan Club        | "Dittos from Longmont, CO"