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romanon
January 11th, 2016, 04:54 AM
Hello i obtained very interesting EGA compatible TVM Multi-Function/2 Color Monitor

29010

29011

i am interesting in this input. What kind is it? Thanks

29012

mR_Slug
January 11th, 2016, 10:49 AM
It may be an early version of the dreaded SCART connector. There was a brief version that had a round connector.

romanon
January 14th, 2016, 12:41 AM
bad news, i connected monitor through 9pin d-sub cable, it looks like some cathodes are burned...

29046

retrogear
January 14th, 2016, 06:10 AM
Looks like you're missing green. Could be cathode gun balance adjustments, RGB connection or a circuit problem, not necessarily the tube. Are you comfortable with removing the back cover and taking pictures?
The RGB level adjustments are usually internal along with a service switch to set the white balance. I am not familiar with this model but most CRT displays are basically the same.

Larry G

romanon
January 15th, 2016, 10:20 PM
I will take pictures of inside next week. But one more thing. As I thought, this monitor also support VGA/SVGA mode after schwitching to analog position and insert 15pin reduction.
Here is picture from windows XP, 800x600x32b. It looks like colors are right, but only bit of left side...

29080

mR_Slug
January 16th, 2016, 05:22 AM
I will take pictures of inside next week. But one more thing. As I thought, this monitor also support VGA/SVGA mode after schwitching to analog position and insert 15pin reduction.
Here is picture from windows XP, 800x600x32b. It looks like colors are right, but only bit of left side...

I may be getting this confused with trinitron tubes, but it looks like a convergence problem. The green is lined up correctly, on the left, but out of wack for the rest.

Also this monitor looks suspiciously like the NEC multisync. Same analog/digital switch etc. From what i can remember the NEC does support 800x600, just poorly, its a bit more than it can handle. I think it officially supported 800x560 or some odd resolution. Perhaps if you feed it 640x480 you would get a better picture. There is still something wrong with it anyway, its just it may be easier to determine/align if it isn't running outside of its official range. If you know this can officially do 800x600 then what i have said should not apply.

retrogear
January 16th, 2016, 05:58 AM
Try other resolutions and connections, etc. but if the problem is always a bright band on the left side, I'm pretty sure I know what the problem is. The bias voltage for the cathodes of the CRT are derived from the HV transformer
and is approx 150-200 VDC. There will be a capacitor maybe 47mfd 200V that goes bad and causes a bright band on the left area of screen and video smearing. If that is what you are seeing, either a schematic or pictures of the
circuit board will help identify which one. Color CRT circuits from that time period are all quite similar.

Larry G

NeXT
January 16th, 2016, 07:02 AM
Just replacing all the caps while you are in there wouldn't hurt. It only costs about $25 and it will clear up any other issues that you might not see.

1ST1
January 17th, 2016, 08:06 AM
From what i can remember the NEC does support 800x600, just poorly, its a bit more than it can handle.

Can't confirm. My Nec Multisync I can support 800x600 very well. But it must be 60 Hz, that's the maximum.