Yet another k7000 issue

mrjiggs

Member

Donor 2013
Joined
Feb 26, 2013
Messages
226
Reaction score
7
Location
Mesa, Arizona
I just recapped and changed out the fly back in my neo geo, k7191. I've degaused the monitor I've adjusted everything and this is the best I've gotten it. The width coil adjusts the lines on the screen but the black on the sides stay the same the lines don't move to the edge. And there's is a ripple across the top and on the left side.

Time to get a rejuvenator?

31ffa9a29043c249356e56386ded3cc3.jpg


c5dce10c9b6d8dc52519f26f923d6e89.jpg


808d943354b3adeb5a6eb0b583a4adc5.jpg
 
Is this the original tube that went with the chassis? What size is the tube? The wavy stuff could be a B+ issue...
 
Is this the original tube that went with the chassis? What size is the tube? The wavy stuff could be a B+ issue...

leaning towards the B+ being off. there are instances where the voltage regulator can fail and it doesn't spike the B+ enough to hit the HV shutdown.

are you using a plastic adjustment tool for the width coil? aside from the fact that using a metal hex tool will result in the tool getting extremely hot, you can damage the core that you physically turn inside it using metal. (so the legends foretell)

you also appear to have either a degauss not working (the coil around the tube not being plugged in perhaps) or a purity issue with the purity rings being out of adjustment. the left side of the screen has a purple look in the white crosshatch. a loose/moved yoke could cause this too, but that would be a more uniform effect across the screen I would think.

the tube looks healthy -- you have white, which means your colors are firing properly. you won't need a rejuvenator for this.

to test B+, there's the large ceramic resistor mounted on the side. one leg of the resistor will be the regulated voltage (on a 25" monitor it should be around 130V) and the other will be unregulated (either 160 or 170V, my brain is mush and can't remember at this moment). if you're seeing about the same voltage off both sides then your voltage regulator is probably toast. :) you use the metal heatsink for the ground.
 
Back
Top Bottom