[sci.electronics] Twisted Sony Multiscan from Hell

bryan@mothra.cs.utexas.edu (Bryan Bayerdorffer) (02/20/88)

	*sigh*, why ME?!  Here I am with my wonderful new Sony MultiScan, only 
it's not so wonderful.  The display is very sharp and very steady, but it's 
twisted.  Here is a more precise description of the problem(s):

	The display has an hourglass shape, that is, the scan lines toward the 
top and bottom of the screen are longer than those in the middle, making 
vertical lines bend outward at top and bottom.  This effect is slightly more 
pronounced near the top left corner.

	The whole screen image is rotated slightly, but noticably, clockwise.  
I.e., the scan lines are not quite horizontal; instead they end up lower on the 
right than they started out on the left.  The scan lines also do not appear
completely straight, but this may be an optical illusion due to the other 
problems and the convexity of the tube.

	The right edge of the display, just where the beam shuts off, is ragged.
About 2mm of each scan line is slightly darker than the rest, and this narrow
vertical zone flickers.  I suspect this is normal, but when the horizontal
position control is adjusted to move this region behind the bezel, there is not
enough overscan on the left edge, even at maximum horizontal size.  The left 
edge is sharp, but has the hourglass problem.

	All of this is with NTSC, both interlaced and non-interlaced.  I've 
tried wiring the sync both horizontal/vertical and composite, each with the 
same results.  
	Has anyone had similar problems with this Amiga/Sony CPD1302 
combination, and been able to fix them, specifically the lack of sufficient
overscan?  Can anyone tell me what it'll take to straighten out the
electron beam?  Does the monitor need to go into the shop?

	Please dispense wisdom, o video wizards!  And AdvThanksance x 10^6!!
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wtm@neoucom.UUCP (Bill Mayhew) (02/22/88)

If the cpd 1302 is brand new as the poster suggests, then the cpd
1302 should be taken to a dealer for a geometry adjustment.  I am
always an exponent for exercising one's warranty.  It's not worth
doing one's self what should have been done at the factory.  A call
to the national service number should yield a nearby qualified
dealer.

  --Bill

pooley@hplabsb.UUCP (Chuck Pooley) (02/22/88)

I'm sorry to hear that you are having such difficulty.  I have a couple
of questions for you.

Hourglass display problem:  Do you have any magnets near your monitor
like (for example speaker magnets)?  If so, this could definitely 
cause you some mischief.  If not, it may need to go to the shop.

Rotation problem:  Which direction is the face of the tube facing?  I'm
serious!  I have noticed on mine that when the tube faces north, that the
horizontal lines are just about level.  But, when the tube faces west I
see the rotational problem you mention...  I believe what is going on
here is that the Earth's magnetic field is interacting with the electron
beam in the monitor.

Overscan problem:  I assume you have adjusted the "Horizontal size" control
on the back of the monitor?  This does have a limited range, but, mine is
ok.

Hope this helps a little,

Chuck Pooley
My opinions are my own fault!
Please forgive me, I'm still learning #%&! vi.

wtm@neoucom.UUCP (Bill Mayhew) (02/23/88)

As Chuck at hplabsb notes, the Earth's magnetic field can
definitely be a source of consternation.  In fact, just the other
day, I was in the local boob-tube shoppe and noticed a
North-South/East-West directional switch big as life on a Zenith
rear projection monitor!  The instruction manual mentioned right up
front that the switch should be set according to the direction that
the set is facing.  The Tektronix scope I have also mentions in its
manual that the trace-rotation pot may need to be tweaked,
depending on the strength of the local geomagnetic field and
orientation of the scope.  (Never mind, of course, big nearby
speaker magnets!)

--Bill

kosakow@canisius.UUCP (Michael Kosakowski Sr.) (02/25/88)

In article <1021@neoucom.UUCP>, wtm@neoucom.UUCP (Bill Mayhew) writes:
> 
> As Chuck at hplabsb notes, the Earth's magnetic field can
> definitely be a source of consternation.  In fact, just the other

    ... talk about tv sets troubles due to mag fields...

> depending on the strength of the local geomagnetic field and
> orientation of the scope.  (Never mind, of course, big nearby
> speaker magnets!)
> 
> --Bill
       
         Speaking of speaker magnets... I have my speakers withins 4-5 ft on
	 either side of the tv and *3 sets* have gradually gotten darker and
	 darker pictures and then barfed.. Anyone know of a possible connection?

krc@cs.purdue.EDU (Kenny "RoboBrother" Crudup) (02/26/88)

In article <1921@canisius.UUCP>, kosakow@canisius.UUCP (Michael Kosakowski Sr.) writes:
>          Speaking of speaker magnets... I have my speakers within 4-5 ft on
> 	 either side of the tv and *3 sets* have gradually gotten darker and
> 	 darker pictures and then barfed.. Anyone know of a possible connection?

Yes. Its obvious. The magnetism sucked all the life outta your pix tube.
Its probably your taste in music. See, because of the left-hand rule
that magnetism uses, instead of the normal, right-hand rule, all
your music is actually represented backwards, magnetically. Therefore,
any recordings that have backwards satannic messages created incarnations
that manifested themselves in your picture tubes, which crave magnetism to
do anything useful, and have a big open space besides. These manifestations
require lots of energy, so when your TV was off, and there was no ultor
potential, it gradually started removing all the photons from the phospor
sprinklies on the inside of the faceplate.



Simple. All you folks who think this is all bullshit- you've never seen
ghosts on a TV picture before?????

-- 
Kenny "_R_o_b_o_B_r_o_t_h_e_r" Crudup		krc@arthur.cs.purdue.edu
Purdue University CS Dept.		
W. Lafayette, IN 47907			If you can read this, thank a
+1 317 494 7842				Hardware Tech!

mike@dodiis2.UUCP (Mike Dollard) (03/08/88)

In article <3324@arthur.cs.purdue.edu> you write:
>In article <1921@canisius.UUCP>, kosakow@canisius.UUCP (Michael Kosakowski Sr.) writes:
>>          Speaking of speaker magnets... I have my speakers within 4-5 ft on
>> 	 either side of the tv and *3 sets* have gradually gotten darker and
>> 	 darker pictures and then barfed.. Anyone know of a possible connection?
>
>Yes. Its obvious. The magnetism sucked all the life outta your pix tube.
>Its probably your taste in music. See, because of the left-hand rule
>that magnetism uses, instead of the normal, right-hand rule, all
>your music is actually represented backwards, magnetically. Therefore,
>any recordings that have backwards satannic messages created incarnations
>that manifested themselves in your picture tubes, which crave magnetism to
>do anything useful, and have a big open space besides. These manifestations
>require lots of energy, so when your TV was off, and there was no ultor
>potential, it gradually started removing all the photons from the phospor
>sprinklies on the inside of the faceplate.
>
>
>
>Simple. All you folks who think this is all bullshit- you've never seen
>ghosts on a TV picture before?????

Satanic Ghosts, no doubt.


Not exactly the way they explained magnetism in the textbooks , but whatever

werks :-) for you. I wonder if music sans satanic msgs will re-juvenate the

phosporous of my tube by virtue of a polarity reversal of tyhe magnetic field?


NOTE : This posting is purposefully double spaced in the hope of

satisfying some programmers idea of a good means of reducing network

traffic by forcing me to post more original text than text I post in

a referenced article resulting in useless dribble such as this

which has at times been refferred to as compufodder a.k.a. even more

resultant useless network traffic and resource comsumption which

accomplishes nothing.


	-michael j.