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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: stewjw on February 21, 2005, 03:34:20 PM

Title: Help needed with inverted picture on Multisync monitor
Post by: stewjw on February 21, 2005, 03:34:20 PM
I have an AMiga 2000 connected to an old NEC Mulitsync II monitor via a commodore VGA adapter and a VGA to 9 pin video cable. Unfortunately, the picture is inverted and upside-down. Does anyone know how to fix this?
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: adonay on February 21, 2005, 03:53:35 PM
I think it might have something to do with ECS since they say you do best in using VGA adapter on AGA computers.dont blame me if i am wrong dont know better :-D


adonay
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: mgerics on February 21, 2005, 04:23:45 PM
Ok, I'll say it...stand on your head!
Seriously, though, I've not heard of this, so my previous statement is my best advice, albeit pretty bad...
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Doppie1200 on February 21, 2005, 05:49:22 PM
Yep it happens to me all the time to. You have gotten your powercable plugged in upside down  :lol:.

No, seriously. Post a photo of this. I think it is pretty unique. Can't help you, sorry.

Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Framiga on February 21, 2005, 06:11:27 PM
only 1 word . . . .impossible.

Its a joke?!?



Title: Re: Help needed with inverted picture on Multisync monitor
Post by: AMIGA-FAN on February 21, 2005, 06:58:47 PM
Oh dear! That's near to impossible, unless you purchased a Monitor where the CRT tube was mounted, inside the monitor case, upside-down! Seriously, this cannot happen, because of the way a monitor works. As someone said, post a picture of this, I cannot (frankly) believe that.

Regards.
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: blobrana on February 21, 2005, 07:25:37 PM
Magic?

its all done with mirrors....
Aminet mirrors that is...

Try Monitor stuff (http://main.aminet.net/search.php?query=mon)

But i remember there was a program that you could tweak yours scan rates and blow up you monitor with etc...

Anyone remember...?
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Mugo on February 21, 2005, 08:12:13 PM
Had your monitor been repaired before ?
Don't you have any other video source, besides the Amiga 2000, to confirm that the monitor is really weird ?
If the YOKE was invert connected to the monitor main board you can see a picture as you described. But it's really odd, as the connector that plugs in the monitor mainboard do not connects reversely.
The only way to do that, is to solder the wires in reverse places, on the YOKE itself. But it could your problem.
If you don't know what a YOKE is, please consider asking a technician some help, because this circuit (horizontal deflection circuit) on monitors and TV sets deals with high voltage.
If i can help in any other way, you can private mail me.

Regards.
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Jope on February 22, 2005, 09:15:30 AM
If the deflection coils are back to front, then that might cause the problem?
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: nex4060 on February 22, 2005, 09:36:45 AM
It's a joke right? :-)

if it's not a joke I would very much like a picture of that, because it is impossible when you consider how a CRT work.

well unless the tube has been mounted upside down, the coils been reversed, some active circutry or software inverted picture :-)
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: xeron on February 22, 2005, 10:31:32 AM
Maybe your eyes have rolled around 180 degrees and you just havent looked away from the monitor long enough to realise EVERYTHING is upside down!  :-P  :lol:
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Lando on February 22, 2005, 11:19:03 AM
Quote

stewjw wrote:
Unfortunately, the picture is inverted and upside-down. Does anyone know how to fix this?


Move to Australia?  
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Darklight on February 22, 2005, 11:39:25 AM
Hey, just because our water drains in the opposite direction, doesn't mean our monitors are upside down as well  :lol:
This is indeed a weird problem.  Hope you get it fixed soon  :-(
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Doppie1200 on February 23, 2005, 11:16:48 AM
Ok! Ive seen the photo of the upside down display.

I am dazzled. It is not like it is out of sync or anything. Just the last scanline is being fed to the monitor first.

You must do some experimenting to determine which device is faulty. From the looks of it I'd say it is your amiga chipset fetching the last line firts working its way up the bitplanes in stead of down.

Are you sure you don't have some sort of virus installed that programmes the chipset to behave like this?

Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Framiga on February 23, 2005, 11:23:31 AM
its a mere joke . . that's all :-)

Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Doppie1200 on February 23, 2005, 11:35:53 AM
We'll it looks very real. So if its a fake it a very good one.
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Framiga on February 23, 2005, 11:39:40 AM
no the picture, its not a fake.

Its the YOKE or the full CRT, installed upside down.

Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Doppie1200 on February 23, 2005, 12:28:58 PM
The CRT is not installes upside down. If you rotate the picture 180 degree you get a mirrored workbench. there it more to this. I'm getting curious.
Quote

Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Tahoe on February 23, 2005, 12:29:49 PM
This can be quite normal. Imagine this: you install a ceilingmount beamer/projector, you WANT your image to be upside down. Maybe this amiga was used for exactly this kind of thing.
Does the A2000 have a harddisk? If so, if you boot from floppy is it the right way around?
There are several utilities for flipping your (WB) upside down/left to right etc.
If all is normal when booting from floppy have a close look at your startup-sequence.
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Doppie1200 on February 23, 2005, 01:42:49 PM
Yep you could use this monitor when its upside down. And then you must use a mirror to get everything right :). So there is a piece of software that can do this. Interesting.
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Plaz on February 23, 2005, 01:58:33 PM
@stewjw

Mugo is right. The connectors inside the monitor are
reversed. Some one did it on purpose, as a joke or as
a mistake while the monitor was open for repair, adjustment
or just just for fun. I did monitor repairs 16+ years
so I know it's possible and I've done it for fun myself once or twice.

There are two pairs of connectors that run from the
YOKE (wire-wound magetic coil on the back of the picture tube).
It is easy to unplug these and reverse then.
2-Wire connector A goes to motherboard connector A
B connector goes to B. Either A and B can be swapped
(A cord to B connector and vice versa) or A and B can be
unplugged, turned 180degrees and plugged back in to give
the picture you describe. If you're not experienced with
monitors, get some one who is. Messing inside one can kill,
or at least leave a very painful reminder why you should
have gotten a pro :-)

Plaz
Title: Re: Help needed with inverted picture on Multisync monitor
Post by: Framiga on February 24, 2005, 11:01:06 AM
and IF the original poster wasn't jokeing, yes those configuration could be used in some coinop/arcades (as Cass (http://www.amiga.org/gallery/index.php?n=929=38) already pointed) or in Teleprompt (http://www.rossiterandco.com/Corporate-Video-Production/Video-TelePrompt.htm) devices.