k4900 uncentered / squished picture

cleverlyj

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so, i just capped the 4900 chassis in my satan's hollow, and am getting a great pic. problem is, i am having trouble centering it. even with the jumper on the down position, i still have a larger gap on the left side then on the right side of the screen.

also, the leftmost 1/4 of the screen vertically is squished, i.e. slightly narrower than the rest of the screen is as well. this is most noticable in the attract mode, as you can see the first s in satan's is narrower than the right s. any ideas there? if i mess with the vert hold and size to get a smaller picture, everything is the same size vertical width wise, however when you try to fill the screen that is when the left size gets squished.

i'm thinking that if i can actually get the vertical to center it should correct the narrower side issue.
 
yeah, i don't have a pot there. and, btw, c313 is the 47uf 250 cap, not the 100, as the 47uf was what it had in it.
 
oh, and if this helps anyone, when i adjust the vert size, if i adjust it to where it will completely fill the screen, i get a black bar on the right side of the screen vertically, which will get smaller and go away if i crank the vert size down.
 
Does it have a vertical Damp control?

no. my other chassis has it, however the flyback is shot. so i got this chassis from pacray and capped it last night. i've actually got it to a point where it isn't real bad right now, just messing with the size and hold controls in combination. just trying to get the colors right. anyone have any tips on getting the color levels right (i.e. the red and green drive/cutoff) along with the focus to get a good pic?
 
no. my other chassis has it, however the flyback is shot. so i got this chassis from pacray and capped it last night. i've actually got it to a point where it isn't real bad right now, just messing with the size and hold controls in combination. just trying to get the colors right. anyone have any tips on getting the color levels right (i.e. the red and green drive/cutoff) along with the focus to get a good pic?

AHA! You mixed old version chassis with new version? Remember that the yokes are different and the major problem is foldover that cannot be corrected.
 
well that explains it then ken. it's not perfect, but i've got the centering etc about as good as i can get it, so i'm ok.

do you have any tips on the colors, though? i'm not real familiar with that the drives and cutoffs do, so i'm having a bit of an issue with brightness and focus versus having the colors not bleed. right now the colors are at the right brightness, but they bleed a bit so the focus isn't right on. do you know how to set those right, or at least what steps i should take in order?
 
The "drives" are what you could consider coarse brightness for that particular color.

The "cutoffs" are what you could consider fine brightness for that particular color.

I usually start with the drives turned exactly halfway. Then set the cutoffs at halfway too. See how the picture looks. If a particular color bleeds, try turning the drive down first.

It really helps to have a Street Fighter 2 board connected to the monitor. The video test pattern really makes it a snap to get the colors right on the money in no time. It displays seperate red, green, blue, and white staircase patterns on the screen at the same time. Makes it so easy.
 
Williams games work well also. The classic ones (Stargate through Bubbles) have a color bar generator and well as grid for pincushion and linearity.

ken
 
Williams games work well also. The classic ones (Stargate through Bubbles) have a color bar generator and well as grid for pincushion and linearity.

ken

MCR games have a white grid pattern that's kinda useful. Just gotta adjust it till it's a good solid white.

IF you can't get it white and not have the colors bleed (my Tron was like that)... you'll have to settle for as white as you can get it. Or check the tube with a rejuve and see if that works well for you (got my Tron to show solid white without bleeding instead of "yellow").
 
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