1 monitor 1 issue for now

[diverdown]

I have 3 arcade machines and each has a different monitor and issue.

Thread edited to solve 1 monitors issues then i will start again for other 2


1st machine is original with NEO GEO MVS metal slug

---- Issue is the horizontal and vertical image is smaller than the screen size, resulting in a black band around the entire screen and a smaller than full screen image. I dont get the whole image in and some clipping occurs.   Do I have to "pull" the yoke out or something?
This machine was ok as a Jamma street fighter but when I changed to MVS and moved it needed serious colour adjustments and degaussing etc.. I fiddled and lost picture size. I dont want to keep fiddling blindly as 1 I have no idea what I am doing and 2 I think i am probably lucky to be alive with what I was messing with anyhow.


The pics below show the monitor sticker (its all i can see to give model but dont know what numbers to look at.

the other pics show the chassis and images of the screen ....... tyhe black between the bezel and the image used to be lit up and showed game screen.
Any help would be great........

[SirPeale]

You failed to disclose the make/model of each of those monitors.

[diverdown]

i did, i will go hunting for a torch and the bloody cab keys

[grantspain]

the 3rd pic down is a kortek ktm-f chassis,you can see the horizontal width coil on the left in the flyback shield-you will need a hex head trimming tool to adjust this(don't use a bloody allen key or you will crack the ferrite core)
there is a vertical size adjustment near it

[diverdown]

the 3rd pic down is a kortek ktm-f chassis,you can see the horizontal width coil on the left in the flyback shield-you will need a hex head trimming tool to adjust this(don't use a bloody allen key or you will crack the ferrite core)
there is a vertical size adjustment near it

I have already screwed this thing all the way in and out....... I will go do so now and see what it does,  ............ now where did i put my allen keys

[grantspain]

if the coil has no affect then there could be a problem with the width circuit,but normally when you get a fault on the width circuit whether it be the transistor or a cap you would get a very wide pic
also some of those ktm chassis had width jumpers further in the chassis

[diverdown]

You should get paid for this............ It worked. I now have the H size full screen.


Now my problem is V size.



I messed with the V size Pot on the Chassis and if i stretch the screen out to fill the top/bottom the image "folds" back in on itself and looks awful. I remember having this issue with another cab and it was something to do with the ArcadeVGA card resolution settings. As this is a Jamme/MVS cab i dunno whats doing it.   

To explain a little more as I increase the V-size the image does get larger. Before it gets to full screen it is as if the image gets reflected and bounces down the screen from the top, like I folded a piece of it back over itself.  As i stretch the image more it gets worse.  Does this make sence?

[grantspain]

yeah its called fold over,that could be a cap faulty.sometimes you can offset that with the vertical hold or shift
and i do get paid for this when i am at work

[diverdown]

Thanks for your help........  i have this looking pretty good atm.  i can live with a cm at the top and bottom.   If I called in a tv repair man could this be fixed?  Or could i buy a new chassis, or is this requiring a "cap kit"


Thanks for your help so far............... goto go..bloody kids.........

[grantspain]

there is no reason to get a new chassis as it seems to work to a reasonable level,i would get a full cap kit for this monitor
a t.v repair man could do it but as its time consuming and you will charged by the hour it would be expensive
you have 2 ways of sorting this at a reasonable cost,fix it yourself or get the chassis out and send for repair
if you are based in the u.k i know a few people who can get this repaired(i know 1 guy who will come out and fix it if you are in the london area)

[diverdown]

about as far from london as you can get. If he had a shovel and time he could dig his way to me here in Aus

Thanks



may research cap kits

[grantspain]

yeah just seen you're in Oz,joey at www.jomac.net.au is the man down your way.
contact him,he will be able to advise the exact cap that is faulty or could repair it for you.
he has a very good reputation
good luck