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Author Topic: Blurry / Double-image on Neotec NT-2515C  (Read 2660 times)

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Crowquill

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Blurry / Double-image on Neotec NT-2515C
« on: February 12, 2006, 02:46:45 am »
When I first got my cabinet home, the monitor had a decent picture, but the power supply was flaky. I replaced the power supply tonight, and now I have a very blurry monitor.

It's a Neotec NT-2515C. Most of the controls for the monitor are on a seperate panel mounted on the side of the cabinet. The focus isn't though. Is there any other adjustments I should make? The image is blurry with double-images showing. Also there are some horizontal lines cutting through the picture.

I'm planning on putting in a cap kit once I find time and improve my soldering skills enough to tackle the 36 caps. This may be happening sooner than later.

Monitor was built July 1994.

All suggestions are welcomed.
« Last Edit: February 12, 2006, 02:49:50 am by Crowquill »
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grantspain

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Re: Blurry / Double-image on Neotec NT-2515C
« Reply #1 on: February 12, 2006, 06:10:14 am »
on your main monitor chassis you have a hi voltage unit called a lopti with two adjustable pots.one is your focus and one is the screen volts(brightness).first turn down the screen volts so you get rid of the flyback lines then adjust your focus pot.why changing a psu would cause this is a little strange-but it might be an idea to check your voltages are good

Ken Layton

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Re: Blurry / Double-image on Neotec NT-2515C
« Reply #2 on: February 12, 2006, 01:08:36 pm »
Telephone the tech support department at the manufacturer (www.neotecgraphic.com) if you still have problems.

That monitor is old enough that it certainly needs a capkit too.

Crowquill

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Re: Blurry / Double-image on Neotec NT-2515C
« Reply #3 on: February 15, 2006, 01:49:04 am »
I finally found the pots to adjust both settings as Grantspain suggested.  I knew they had to be around the flyback, but didnt' realize they were just inside a hole in the side of the frame, camoflaged by dust and dirt. I now have a pretty decent picture. There's a bit of a pattern running through the screen and a bit of ghosting still, but hopefully the cap kit will take care of it or at least give me a good place to start looking for other solutions.

Any idea what the giant white knob is for? I can't find it on the schematics and adjusting it doesn't seem to do anything.

BTW, I emailed neotec, but still haven't heard back.

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Re: Blurry / Double-image on Neotec NT-2515C
« Reply #4 on: February 15, 2006, 02:07:17 am »
You need to telephone them as they don't usually respond to email.

Fozzy The Bear

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Re: Blurry / Double-image on Neotec NT-2515C
« Reply #5 on: February 15, 2006, 03:09:19 am »
Any idea what the giant white knob is for? I can't find it on the schematics and adjusting it doesn't seem to do anything.

The white pot is a multi turn ceramic (Cermet) they usually control the gain on the screen side bow on older monitors.... BE VERY CAREFUL! They are delicate and can be damaged very easily, they're a devil to get replacements for as well, as I don't think anybody actually manufactures them any more.  Modern monitors use a different type of automatic screen regulator circuit to control the bow.

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Re: Blurry / Double-image on Neotec NT-2515C
« Reply #6 on: February 15, 2006, 01:10:43 pm »
if you now have a ghosting on your colours could be just down to colour gains too high or your contrast-try adjusting these first before going down the cap route,as for you pattern if its flyback lines(slighlty diagonal lines that go trom left to right on the whole screen)then you need to turn down your screen volts,which is the other pot on the lopti next to the focus otherwise the pattern could be your chassis earth missing-we did have a problem many years ago when this fault could be rectified by linking the common and earth on the psu-but this depends on how old your cab is.