Blurry Monitor repair?

[rivacom]

I picked up a tekken Tag machine not too long ago and everything in it seems to work fine,  except the monitor seems to go real blurry after about 20-30 minutes of use.  It also seems to add white diag. lines through it at about the same timeframe.  However when I first turn on the monitor, it works great.  I haven't opened the back to check anything as I don't believe the keys I was given work with the back door. 

In any case, is this a sign of a bad monitor?  Is there anyway to fix it and keep the original monitor going?

[grantspain]

its either a dry solder joint on the flyback transformer or the flyback transformer breaking down

[Malenko]

its either a dry solder joint on the flyback transformer or the flyback transformer breaking down

that.

you can drill the lock out to open the back door.

[qrz]

could be a cathode/grid issue in crt - try a rejuve
or a problem in the focus/screen divider in the fly.
is there a slight -snap- when it occurs ?

[rivacom]

Maybe?  I'm not sure as I'm usually not paying attention when it occurs, I don't believe so however.  I think it just slowly fades to blurry and the white lines fade in.  I'll have to see if I can catch it.  Where would I preform a rejuve?

I do need to drill the lock or something soon as it'd be nice to have access to the rest of the cab, Is a dry solder joint easy to find/fix?  My luck it's no, but maybe there is some good news.

[rivacom]

Any advice?

[lilshawn]

Where would I preform a rejuve?

you need a special piece of equipment to rejuvenate a tube. not exactly what you need, but some TV repair places can do it for you.

sounds like you might have a problem with the high voltage transformer. (often called a LOPT or "flyback")

inside the transformer is a small network of resistors that allows the high voltage beam to focus on the screen properly.

you may have an issue that is causing the the flyback to run hot , causing the blurring and the lines.
you may have an issue with the main power supply to the flyback (high or low voltage) can cause this too.

[rivacom]

Wanted to Rez my thread now that I have a little more time on my hands.  So I have 2 videos, one of the screen when i first turn it on and the other from about 45 minutes into having it on.  Is there anything I could do to try to fix this before hand?

   - Before

    -  After

[grantspain]

what model monitor is this?

[rivacom]

Phillps


Monitor by rivac0m, on Flickr

[grantspain]

thats the tube,i need a photo of the chassis(monitor board)

[rivacom]

Looked over and a lot of the board is hard to see.  Only tag i could find is this, tell me if this is or isn't what i should be looking for.

[lilshawn]

says right on the label - "Model No. Neotec 2515C"

that'd be it.

[ed12]

hi
if it start's up in foucs ?
then start's to fade to blurr
your crt is done
that simple

ed

[rivacom]

Not that I'm doubting you, but what is causing the issue to classify it as dead?

[grantspain]

does it focus when you adjust the focus control on the flyback,do the flyback lines go when you adjust the screen volts on the flyback,can you adjust contrast and it make a difference?

[ed12]

hi
a simple rule of thumb is in order here
if u need to keep doing a :set: set of adjustment's
then u have a weak tube
it is that simple
u can rejuve till the cow's come home
u can adjust contrast/brightness/fous/screen
will not matter
tube is on it's way

ed

[MonMotha]

I wouldn't necessarily guarantee that.  It could be that something's drifting on the electronics side as things heat up (e.g. B+, which will mess everything up) or just a cold solder somewhere that goes open or closes itself at operating temp but not room temp.

There's certainly a chance of a bad tube, yes, but nothing I read so far makes me jump to that conclusion immediately.

[ed12]

hi
here's your proff in the pudding
take the tube in ?
have it chked on a b@k or a sencore tester
have it heated up
see what the result's are before and after heat-up
that there is the trick in the tail
anything under 70% through out
anything over that,consider a chassic problem
it is about that simple

ie do your test's first

ed

[boardjunkie]

Bah....its just a flyback on the way out. Seen this same problem many times....the WG 4900 was a big offender. If the tube was getting bad it would *never* focus and always look washed out.

Just to be safe I'd check the main B+ voltage at power up, then when it goes out of focus and make sure it stays the same. Usually if the B+ sags (for whatever reason) the pix will get smaller.