Help: Three horizontal lines accross the top of my screen (Solved)

[brad808]

Hey guys I'm trying to get rid of these 3 and a half horizontal lines at the top of my screen and I can't seem to get it figured out. The monitor is a 25" Hantarax Polo and I'm wired in through a VGA connector using soft 15khz. I've tried two different computers now and reattached all of my connections on the input side so I'm thinking possibly an adjustment I can do on the monitor?

Anyways here are some pics hopefully someone can help me out a bit

http://img825.imageshack.us/i/img0108.jpg/

http://img256.imageshack.us/i/img0109l.jpg/

http://img696.imageshack.us/i/img0110byp.jpg/

[grantspain]

flyback lines-your screen volts is too high
the screen volts is next to the focus adjustment on the flyback transformer,turn the screen volts anti clockwise until the lines go

[qrz]

agreed that the screen appears to be set a bit high .

if still present , check the boost cap on the vert output ic     100-470uF/25-50v typical

[brad808]

Small update on this. Still havent been able to figure it out completely but I've narrowed it down to it being some setting in windows. Seems very strange to me but maybe not to someone else.

Basically if I open up a window ie my computer, then the monitor looks great... the lines go away at the top the background actually turns to a good solid black and all looks good. The second that I minimize the window into the taskbar, the lines at the top come back and my blacks turn to sort of a grey colour. Definitely not black like when the window is open.


Any suggestions?

Heres some more pics, all that I have done differently in the two pics is minimized "my computer"



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[brad808]

I'm also using powerstrip to get my resolution down to 640x480


Another update it turns out if I drag a window down to the bottom of the screen the lines will start to appear

[lilshawn]

have you noticed your black is gray?

your screen is set too high. it's on the black flyback transformer. turn it down a bit.

those lines are called RETRACE LINES. it's produced when the beam is "FLYING BACK" to the top of the screen after the end of the SCREEN TRACE. (see what I did there?)

so when the beam voltage or SCREEN is set too high, the beam, (which doesn't turn off, it's on scanning the screen horizontally all the time and normally not visible during the RETRACE scan back to the top of the screen) shows as it "slows" to the top of the screen to begin another trace. it doesn't really "slow" it's a complicated charge/discharge cycle that happens with the vertical system...

if you look really close, (or turn up the screen even more) you can see the retrace from the bottom to the top. you just notice it at the top because the beam is slowing towards the top getting ready for the next scan.

long story short: turn the "screen" down.

EDIT:

P.S. the reason your lines "disappear" when a window is opened is likely because the energy is being dumped into displaying the window. (if that makes sense).... on a pure white image your B+ voltage (which is directly related to your screen voltage) is at it's lowest, on a black image it is at it's highest. this is due to the fact that the system doesn't have the ability to regulate the voltage when the load goes up and down. the screen (being a tad too high) is showing the retrace lines because the screen voltage is higher. they would go away when something is displayed, because the voltage starts to go down. (being pushed down by having to use up energy drawing the screen.)

[brad808]

have you noticed your black is gray?

your screen is set too high. it's on the black flyback transformer. turn it down a bit.

those lines are called RETRACE LINES. it's produced when the beam is "FLYING BACK" to the top of the screen after the end of the SCREEN TRACE. (see what I did there?)

so when the beam voltage or SCREEN is set too high, the beam, (which doesn't turn off, it's on scanning the screen horizontally all the time and normally not visible during the RETRACE scan back to the top of the screen) shows as it "slows" to the top of the screen to begin another trace. it doesn't really "slow" it's a complicated charge/discharge cycle that happens with the vertical system...

if you look really close, (or turn up the screen even more) you can see the retrace from the bottom to the top. you just notice it at the top because the beam is slowing towards the top getting ready for the next scan.

long story short: turn the "screen" down.

EDIT:

P.S. the reason your lines "disappear" when a window is opened is likely because the energy is being dumped into displaying the window. (if that makes sense).... on a pure white image your B+ voltage (which is directly related to your screen voltage) is at it's lowest, on a black image it is at it's highest. this is due to the fact that the system doesn't have the ability to regulate the voltage when the load goes up and down. the screen (being a tad too high) is showing the retrace lines because the screen voltage is higher. they would go away when something is displayed, because the voltage starts to go down. (being pushed down by having to use up energy drawing the screen.)

Ah finally thank you. Soooo that did make the lines go away and made my "blacks" black which is good. The screen is quite a bit darker now even with the brightness setting turned up all the way. Is there anything else I can do to bring up the brightness without turning the screen voltage back up?

Thanks for all the help

[lilshawn]

if the tube is wore out, you might not get a decent picture out of it, but there is something you can try, you can turn the drive gain up on the guns. basically you push more color out to the screen. the small circuit board that is attached to the neck of the tube should have the adjustments.

what you want to do is display a color gradient on the screen:



what you will notice is that the colors will be okay on the right side but get very dark to black (probably before the halfway point) you want to EVENLY turn up the DRIVE AND/OR the GAIN settings to bring the color further across the screen.

you want them to be even (red green and blue) if they are uneven, your whites will be tinted. if you run out of adjustment (maxed out) on one color before the others you will have to turn the others down to match the lowest.

this MAY give you some additional low level color brightness at the cost of reduced color separation at high color levels, although this is unnoticeable in 99.9% of cases.

your other option is having the tube rejuvenated. some people swear by this, others recommend not doing it at all. a test can be performed to see if the low output you are having can be remedied with a rejuvenation or not (same equipment). It's pretty easy, takes about 5 mins. may make your tube look better. ALSO may render your tube unusable or fail prematurely. so try this at your own risk.

[brad808]

OK new problem now, moved my arcade monitor and reinstalled windows. Problem I'm having now is the screen isnt clear at all its very hard to read anything, There are diagonal waves of some sort making everything blurry. I'm not sure if it has something to do with me reinstalling windows or something came lose while moving (I checked every connection I could see and all seemed to be good).

Any ways here are some pics hopefully someone out there can give me some insight.

It's almost like a rolling checkerboard effect....

As always thanks to anyone that can help

[brad808]

Holly crap I actually figured it out!! Turns out that an arcade power supply (not connected to anything but plugged in) was causing the issue. After doing a bunch of reading I came to the conclusion that it was a grounding issue and after trying to ground my monitor/videocard/powersupply/frame to each other in different methods I finally looked at the jamma power supply and thought to myself why is that even in here there are only power in's connected and nothing on any of the outputs. Unplugged it and instantly everything went clear. Just had to make a few small adjustments again because everything was a little bit off including the flyback which I was having issues with since I started this mame cab.

Now finally I see the light about what people have been saying about how good an arcade monitor looks I've secretly been searching the local classifieds looking for a 25" tv to throw in there and replace the stupid thing because I couldn't for the life of me get a good solid signal that I was 100% happy with. I had signals that were pretty good looking but there was always something not right and definitely not anything that I was "wowed" over.

Any way glad it was something stupid and not something that would cost me more money!


..... what to tinker with now...