21" Trinitron CRT- several light-colored horizontal lines visible on dark background

21" Trinitron CRT- several light-colored horizontal lines visible on dark background

@ 1024x768 res there's about 10 slightly non-horizontal lines going across the screen clearly visible when the screen is dark (before loading a game, etc.). when i change resolution the number of lines changes, more lines for higher res, less for lower res.

anyone ever see this happen with AG CRTs? the thing is it occasionally doesn't have that happen, which is weird. it didn't do it before.

Sounds like it isn't tuned right. I've tuned a few screens and they will do that if the focus potentiometer is not set correctly.

my 20" gateway dose the same thing, two lines. Ill be interested in the answer and will have to try what thid said

the sony Trinitron tubes always have two lines, splitting the screen into thirds. They are a physical item on the back of the screeen, i can't remember the details though. But you problem sound differant to those lines.

Mine did that until it got warmed up. Multiple dia. lines. Then the line started showing up more often. Then over Christmas with my monitor off for a week, it never would turn on. Hope yours isn't on its last legs.
Can you capture a pic of it?

There should be two horizontal lines on your monitor, these are, as it was explained to me, supposed to be there. They are only noticable on white for me however.

Hipcrostino said:

the sony Trinitron tubes always have two lines, splitting the screen into thirds. They are a physical item on the back of the screeen, i can't remember the details though. But you problem sound differant to those lines.

Click to expand...

The two lines are called damper wires and they hold the vertical aperature grill wires in place iirc. They are normal. More than 2 is not, I've never had this issue and haven't ever had to tune an AG monitor beyond the usual focus and geometry OSD adjustments so I can't help more Thideras sounds like he has an idea about it.

I did have to tune one non-AG shadowmask monitor. The OSD controls weren't doing enough so I had to remove the external plastic housing to reveal the adjustment pots. There were 3 holes for adjustment and I used my old Radioshack plastic TV/CRT adjustment tools (they are basically long small diameter screwdrivers made of plastic to make them non-conductive) to turn the pots. They are normally factory service type adjustments which is why they're hidden inside the plastic housing but still accessible outside the metal shield cage. Remove the plastic housing and see if you can find any adjustment holes. Just be careful not to go inside the metal cage at all with any metal tools nor remove it, the voltages in there are lethal.

Do some googling you may be able to find info about adjusting monitors.

"@ 1024x768 res there's about 10 slightly non-horizontal lines"

"non-horizontal"

Why you're running at 1024x768 on a 21" I don't know but I had the same issue on my p260 in two places, only mine were vertical. That monitor was so out of focus you couldn't read 40pt text until it made a very loud SNAP after being plugged in for ~5-15 minutes and went into it's normal (blurry) focus.

I also had this problem with a veeery old generic 17incher right before IT died, so i'm guessing it's just a sign of monitor age.

It doesn't sound like the normal 2 lines associated with Sony Trintron picture tubes.
It's not normal that's for sure. You can try adjusting them out or possibly get rid of it.
It would be a good excuse to get a large (19" or bigger) LCD.
Just a thought.

Just a thought... Have you tried moving your monitor cable around? It could be some sort of interference, or a sketchy connection somewhere. Also see if you've got a degauss function in the menu, and do that.

It prolly is an adjustment issue as has already been said, but regardless, it'd be a good idea to knock out the basics before you start screwing around with the adjustment pots... they can be a bit of a pain to get right once you mess with 'em. (Don't let that scare you off... just remember it's prolly going to take a bit of delicate fiddling to get 'em tuned in just so.)

Sounds like you have the infamous retrace line issue.. I had the same problem with a Sony G400 monitor, The actual cause of the problem isnt known but it can be fixed by lowering the G2 voltage of the CRT.. Unfortunately in order to do this it requires a special service cable (about $30) which gives you access to the monitors firmware, it hooks up to your PC's Serial port (newer motherboards will most likely require a serial port addon but they usually come with it) and the other end of the cable plugs into a special service port on the monitor, then you use a program called WinDAS to make the adjustments.. It works on just about all Trinitron CRT's, Here's the before and after pics from using the cable & software: http://icrontic.com/forum/showpost.php?p=392396&postcount=454

(click on the "Dell monitor to bright" link in the upper right corner of the page to see the whole thread.)

You didnt specify which model Trinitron you have but a lot of them have an "Image Restoration" option found in the Color menu on the monitor, If yours has it first turn up the brightness setting to about halfway (even if it looks way to bright) and then run Image Restoration.. Hopefully the monitor is a lot darker after running it (turn the brightness back down afterwards) Doing this sometimes fixes the problem but if not your only option is to use the Windas software & cable.

I have the same issue

lol thats big
And do they move? Cause when I have two CRT screens near each other, they get lines traveling up or down the screen.

I have 3 of the 21" sony (dell) Trinitrons (great monitor). Here is my $.02

1. interference!, find and remove all magnets/speakers within a 5' radius

2. power, this monitor uses 160watts. using a cheap (thin) power cord will weaken the signal. try to have the monitor pluged straight into a wall, and not on a power strip that has 8 things pluged into it.

2. power, this monitor uses 160watts. using a cheap (thin) power cord will weaken the signal. try to have the monitor pluged straight into a wall, and not on a power strip that has 8 things pluged into it.

Click to expand...

This is definitely valid advice, but I'm gonna hijack for a minute, to clear up a point. Anyone not interested, skip the darker text. It's still an issue of interference in this case, rather than the amount of power the monitor draws. More stuff on a power strip/outlet/circuit means more chance of interference being introduced into the power stream. Any difference you see with a thin cord would probably be a result of grounding/shielding rather than "weakening the signal."

Small gauge wire does have more resistance per unit of measure than large gauge wire, but it's really a non-issue in this case due to the short length of the cord and the properties of AC power. Otherwise, as long as the wire is of sufficient gauge to supply the necessary current, which is, in this case, about 1.4 amps, then it is enough to use as a power cord. Allowing even a 300% margin for power-on current spikes and such, it'd be perfectly OK to use 22ga wire to power that monitor. I've never seen that type of power cord in anything smaller than 20ga.

But, anyway... Back to the OP. Yeah, check where the thing is plugged in, make sure it's not on an overloaded power strip, and also see if you have any other appliances on the same circuit that could be causing interference as well. This could include a fridge, ceiling fan (or anything with an AC motor, really), and even flourescent lights can cause trouble.

But if the retrace line issue is, in fact, infamous, then that's a good possibility too.