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Main => Monitor/Video Forum => Topic started by: ToplessZ on March 14, 2008, 02:47:01 pm

Title: K7000 Crappy Image
Post by: ToplessZ on March 14, 2008, 02:47:01 pm
I bought a cyber sled machine the other day and it has 2 K7000 monitors in it.  One of them has a very dull picture(no real color and kinda blurry), the other has a real crisp picture but is has this weird shadow that is about 3" that seams to "flow" down the left side of the screen. 

I bought 2 K7000 repair kits from Bob Roberts.  I installed the first one on the crappy picture monitor.  This includes flyback, cap kit, and HOT.   Even after replacing all of these items the monitor is exactly the same as before!  I have tried to adjust the focus,screen, brightness, contrast but nothing seems to get it looking sharp and crisp. ANY Suggestions???

I havent done the second monitor yet, anyone know what causes that shadow on the left side of the screen?
Title: Re: K7000 Crappy Image
Post by: Arm123 on March 14, 2008, 03:47:39 pm
Assuming you played with all the color / contrast / Brightness pots...   The tube could need a rejuvenation.
Title: Re: K7000 Crappy Image
Post by: Lutus on March 14, 2008, 04:43:41 pm
If they are the same exact chassis, swap the tubes and see if that clears up the problem.

Only do this after double checking the yoke ohms and such.  Not real sure about this part.
Title: Re: K7000 Crappy Image
Post by: Kevin Mullins on March 14, 2008, 08:17:06 pm
I wondered who was going to nab that Cyber Sled up......   :cheers:

I'd also recommend the chassis swap, that'll give you a good idea whether to look at the tube OR the chassis.
Title: Re: K7000 Crappy Image
Post by: qrz on March 14, 2008, 08:32:38 pm
have u checked/changed c56(22uF/160v) and c57 (47uF/160v) c204 (4.7uf/160v) ?

also check c10 (33uF/16v) c23 (47uf/25v) and c46 (470uF/16v)

qrz
Title: Re: K7000 Crappy Image
Post by: Ken Layton on March 14, 2008, 11:03:55 pm
I bought a cyber sled machine the other day and it has 2 K7000 monitors in it.  One of them has a very dull picture(no real color and kinda blurry), the other has a real crisp picture but is has this weird shadow that is about 3" that seams to "flow" down the left side of the screen. 

I bought 2 K7000 repair kits from Bob Roberts.  I installed the first one on the crappy picture monitor.  This includes flyback, cap kit, and HOT.   Even after replacing all of these items the monitor is exactly the same as before!  I have tried to adjust the focus,screen, brightness, contrast but nothing seems to get it looking sharp and crisp. ANY Suggestions???

I havent done the second monitor yet, anyone know what causes that shadow on the left side of the screen?


Second monitor just needs a capkit. First monitor probably has a picture tube problem and needs to be put on a rejuvenator.
Title: Re: K7000 Crappy Image
Post by: ToplessZ on March 16, 2008, 09:35:26 pm
Well I did a full repair kit to the second monitor, the shadow is gone, but now the picture just isnt as sharp as it was before doing the repair.  When you try to adjust the focus on the flyback its like you need just a slight more turn on it to get the picture clear but the knob wont turn anymore, the flyback that comes in Bobs repair kit is slightly different then the original, so I feel like the replacement flyback isnt strong enough?  Both of my K7000s now have had the full repair(cap kit, replacement flyback, HOT, and fuse)and both arent really sharp.  The first tube probably needs a rejuv, but the second screen was sharp before the repair kit from Bob Roberts.  Has anyone had any issues like this with the replacement K7000 flybacks from Bob Roberts?  Im probably going to put the old flyback back into the second chassis and see if it sharpens the picture....
Title: Re: K7000 Crappy Image
Post by: qrz on March 16, 2008, 09:58:59 pm
in tv work, the flyback either works, or it doesn't .  so, if it is working ... why change it   :dunno
 some of the more recent generic flys seem to be causing problems in many different sets.
reported symptoms are similar to ur description, along with extreemly short life spans and other oddities...
counterfeit components are also becoming an issue .  those "bargan" parts may not be what one thinks  .

qrz



Title: Re: K7000 Crappy Image
Post by: Ken Layton on March 16, 2008, 11:41:57 pm
Buy your replacement flybacks from Zanen Electronics. That's where I get them and I have never had a problem with theirs.

Oh yes, I forgot to mention this, but you do know that the wire colors on the replacements may be different than the original flyback?
Title: Re: K7000 Crappy Image
Post by: qrz on March 17, 2008, 05:58:58 pm


Oh yes, I forgot to mention this, but you do know that the wire colors on the replacements may be different than the original flyback?

umm..,  the focus wire IS a heavier guage than the screen .........never seen one (yet) different in that regard  :dunno   
actually, i mispoke  :-[  the INSULATION is greater due to higher voltage. making it appear to be a heavier guage.
(srry for any confusion this may have caused)

i would think that applying the focus voltage to the screen terminal would cause arcing on the socket's spark gap
(likely burn it ) and perhaps pop any bypass cap ( i.e like a .001@2kv  ) on that line .

i'd sure hope that anyone doing so would have the sense to remove power IMMEDIATELY

on a lighter note , i once had a boss that insisted i'd installed a resistor backwards because "the color bands didn't go the same way"  -  and he was serious  :o     :laugh2:

qrz
Title: Re: K7000 Crappy Image
Post by: ToplessZ on March 19, 2008, 09:33:30 am
ok,  I got the wires correct, I checked them.

On a good note:  I had a friend over last night and we played adjustment hell with the chassis's ,,, after finally tweaking them, the monitor with that had the shadow and was sharp is now looking pretty good.  it took alot of color adjustments and then going back to the focus and screen to fianlly get it to look sharp and crisp again.  So that monitor is now good.  the first one is actually sharp but it has really dull color still, it didnt matter what we did, so Ill try to see if Mr. Witchboard can let me use his tube rej if it fits this model..

It helps to have someone else there that can tell you what the screen looks like when you are turning the knobs! I played hell running back and forth for 3 days trying to do it myself! 8)
Title: Re: K7000 Crappy Image
Post by: grantspain on March 19, 2008, 09:42:39 am
why not just use a mirror to see what you´re doing
Title: Re: K7000 Crappy Image
Post by: ToplessZ on March 19, 2008, 10:32:27 am
Cyber sled cab is huge and I have 8 other games in my garage keeping me from being able to move it around, not to mention the last time I took one of my wifes mirrors out into the garage she about killed me!  :notworthy:
Title: Re: K7000 Crappy Image
Post by: SirPeale on March 19, 2008, 11:03:59 am
Use a handheld makeup mirror.