Horizontal Issues G07

[FrizzleFried]

I have an old Electrohome G07.  The only way I can get it centered horizontally is to put the jumper on the left post at the Horizontal position tabs....then adjust the horizontal frequency until it matches up...unfortunately,  when I switch to any vertical resolutions,  the picture is all jumbled....so I adjust back to JUST WHERE it shows the vertical games...switch back to full screen (640x480 or any H resolution) and I am back to having an inch on the left. 

Do any of the other controls affect the H Freq. and where it goes out of whack with vertical resolutions?

Also...why would I get a very slight wave motion with low light  images on screen at certain resolutions and a much more pronounced wave with high light images on screen (the wave appears to be a pixel or two back and forth)...

Also...can someone show tell me how to measure the B+ voltage?   I have no idea how to use a multimeter (I guess it's time to learn).  I have one though!



Thanks for helping this newb!

[Ken Layton]

Remember that the Electrohome G07 was designed in 1980 specifically for arcade video applications & standards. It was never intended for use with a computer or for use with changing video standards/signals.

[FrizzleFried]

Ken, 

Yeah...I know.   I have found a few resolutions that look the best.   I think I am going to have to sacrafice semi-authentic game geometry for the sake of a good image.   I am actually quite happy OVERALL with the image I get from the old lady.   It's hard to believe she's going on 27 years old!

I am just now most annoyed with the wavy top portion of the screen IN CERTAIN RESOLUTIONS only.  The annoying thing is before I upgraded to the 3200,  this monitor didn't exhibit this issue at this resolution.    I have also had issue with a garage door opener (wireless) not working while the computer is on.

I am considering putting the XP2100 back in as it played all the games I play fine anyway...

Not sure....I'll tinker some more.

After a little bit of research,  I found the info I needed to test the B+ voltage,  which was at 113.5 volt.  I adjusted it up to 120v per the instructions I read...I actually used my multimeter for the first time...w00t.

Living on the edge I tell  ya!

I find that the resolution that MAMEWAH RES TOOL automatically sets for the NEO GEO games look fantastic...so I think I may go with that res for all my horizontals...not sure about the verticals yet.

[FrizzleFried]

Anyone know if the G07 Sync circuit upgrade as described here:

http://homearcade.org/BBBB/g07notes.html

will rectify the curl I get in some resolutions at the top of my screen?   Sounds like it would,  but of course,  it was written with PCB's in mind,  not necessarily a computer/ArcadeVGA card.   I did check and the upgrade has NOT been done on my chassis.

[FrizzleFried]

Yet another strange thing...when I switched Mortal Kombat over to the same resolution as the NEO GEO games,  while the NEO GEO games did NOT cause the monitor to wave,  Mortal Kombat still does regardless...hmmm...

[Aurich]

IIRC Mortal Kombat has a funny refresh rate, probably the problem.

[FrizzleFried]

Aurich,

I'd agree except that my verticals are all doing it as well (Donkey Kong,  Galaga, etc)...

I dunno...I am considering purchasing another chassis to mess with from ebay.