Another monitor issue thread. TECHS PLEASE HELP!!

_jmfr

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So i've had my umk3 up and running for awhile, and i decided to strip it down, and give it a makeover. There was a loose wire somewhere on the pcb on the monitor chassis, So i tracked it down (the blue wire in the picture) ans did my best to put a little solder on it. Well, when i hooked it back up to test, no picture. All i get is a white screen with lines. There is alot of hum coming from it, and the color tube doesnt even light up. Any techs have any advice? Where should i start?
 

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What picture?

First off, leave it off until we get this straightened out.

Second, have you tried disconnecting that wire? It might not connect where you think it did.

Third, how about a pic of the chassis so we can ID which one it is, as well as all your connections....
 
the MO8X you took a pic of is the tube number, useless unless you are rejuving it , you need the chassis number for future reference, but to reiterate what gamefixer has already said, look for solder bridges and maybe touch up tour header pins , look for cracked solder joints as well. these k7xxx series are infamous for having heat related cracks
 
Im removing the pcb on the monitor so i can better look at the componets. Now, the dreaded red wire that runs to the picture tube from the flyback needs to come off. I hear the best way to dicharge it is to run a wire off a skrewdiver and ground it, then touch the skrewdriver tip underneath rubber cover on the monitor. I know you techs have proper tools for this job. whadda think?
 
LOL what you just deacribes IS the proper tool, some guys waste money on a HV probe but unless you are checking HV , they are unecessary , screwdriver, length of lampcord and aligator clips do the job
 
sometimes it will while others it will not. do it once, wait a few minutes , try it again , remove the anode and remove chassis. before you reassemble , do it again because after a tube sits for a while it can and often does build up a charge again
 
yes we just posted a video on how to do this you can see on our site or check you tube there are some really good ones out there
tim
 
one more thing. After discharging it, is it ok to remove the anode from the tube? the main reason for doing this is so i can remove the pc board
 
Discharging a monitor, while dangerous, is not nearly as bad as first-timers think it will be. Just take your time, be very deliberate, patient, and it will be just fine. Common sense goes a long way. Keep your free hand in your pocket, make sure your working hand is not close to any of the monitor chassis, work slow, and you'll be fine. After you're done, you'll wonder what the big deal is.
 
after removing everything, the model no on the chassis read 25k7197. It also reads wells-gardner, but the picture tube say Phillips. ?????? Any techs in Tennessee?!?!?!
 
many different tubes used with the same chassis, no worries the chassis is the number that counts. 25" and above crt's share the same neck pinout. wg71xx series has a lot of heat stress crack issues , touch any and all suspect joints up
 
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