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Betson Imperial Multisync problem
Dave_K.:
Ok, so I went up to see the Betson techs in person today during lunch, and came back with some good/bad news. First I want to say the techs at Betson were very helpfull and supportive of me...even though I was a consumer and not a vending company. Ok so here is the short of it...
Good news is, you won't have to go through the hassle of returning your monitors, because nothing is broken on them.
Bad news is, it appears the rotation control and v.focus are not fully implemented. The menu's are there, but it appears the monitors are not wired up to do this. It could be something they were planning on implementing but never did (and forgot to remove the options from the menus)...I don't know. My contact at Betson is going to follow up on this and I'll be sure to let everyone know.
Ok now to the longer version.. I drove up during lunch today to exchange my monitor. Again, everyone was helpful and ready to make an exchange. We took a brand new RT model out of the box, and powered it up right there and tested out the controls. Sure enough, rotation and v.focus did not work. In looking closer at the monitor, we could see there was no connection between the yolk coil and the PCB to even allow this type of operation. They were just as curious as I why this was. The tech said he would call around and find out what the scoop is on this.
In the service manual (as Kevin pointed out above) there is mention of a CN402. The schematic shows CN402 as a 2 wire connection from the PCB to the yolk coil. There is no CN402 that I could find, nor a 2 wire connection to the coil.
So what are we to do? Well I hate to say it, but we have to live with these imperfections. With a little determination, I was able to make enough adjustments to the workable options to make my problems less noticable. Thankfully these issues are only in 15khz mode, as the VGA modes looks fine to me. Even in 15khz mode, I don't notice the squishing or rotation as much while I was playing games ...but of course like owning a new car, you know where every single scratch is on your new baby. :( I doubt others will ever notice.
One last note. It may be possible to adjust rotation by manually adjusting the hex slugs in the yolk coil, but I'm really not going to risk screwing it up any further. There is also the manual focus knob on the flyback that you could also tweak if you are a perfectionist. In all there are still more digital controls on this than the 9200 and with a lot of tweaking you can get it to perform within arcade monitor specifications (however loose those may be to PC monitor specifications). ;D
KevSteele:
Wow...thanks for the update!
Not exactly good news, but at least it's nice to know what's going on.
Kevin
jimj:
Thanks for the update Dave_K. After getting to actually play some more games I think my monitor is ok too. I've only got two issues left that I'm not sure are normal.
1. After doing the degaussing dance my bottom right hand corner looks much better. In an all red screen you can still see a little discoloration in the bottom right hand corner, but I've never been able to see it in a game. However my degaussing dance seems to have introduced a little discoloration in the bottom left corner now. :'( It's not as bad as my bottom right used to be, but you can notice it in all the Nokia color screens. As of yet I haven't noticed it in gameplay either. Should I perform the voodoo degaussing dance again? Am I more likely to make the problem worse or better?
2. All games that run at 288x224 (ala Pacman) appear to shake left and right. This is most prominent during the game info screen. I probably wouldn't have even noticed it if it wasn't for the game info screen. However, now that I know it's there I can see if in the game if I look closely for it. Upon closer inspection it appears that the image isn't actually shaking, but rather the pixels on the edge of letters, pictures, etc. are flickering. This gives the impressing that the screen is shaking horizontally. If I look really closely at other resolutions I can see this effect too, but it's not nearly as noticeable (and even at 288x224 it hasn't bothered me during actual gameplay yet). So my questions are:
Has anyone else seen this effect?
Can anything be done to fix this, or is this just another feature of arcade monitors that give them more character? :)
KevSteele:
jimj:
1. It should be fine to do the degaussing dance again. I've done it several times - with each run you should be able to "fine-tune" the colors on your display.
My Betson has some slight red-color purity issues when it's up against the wall (could be a power line, dunno) - moving the cab out gets rid of it.
2. The "shake" could be due to an interlaced video mode being used. I'm just guessing here, but it might be the monitor is running at 512x512, which is "flickery" on my Betson because it's an interlaced video mode (the monitor draws the even lines first, then the odd). Try experimenting with some other resolution settings for Pac-Man and enable/disable hardware stretch, if the flickering drives you nuts.
Kevin
jimj:
--- Quote from: KevSteele on December 03, 2004, 09:07:14 am ---1. It should be fine to do the degaussing dance again. I've done it several times - with each run you should be able to "fine-tune" the colors on your display.
--- End quote ---
By "fine-tune" do you mean pray that it happens to work this time? :) I just tried degaussing it again, and it didn't seem to make any difference. If repeated degaussings don't fix it am I just out of luck, or would Betson be likely to help me with something like this?
--- Quote from: KevSteele on December 03, 2004, 09:07:14 am ---2. The "shake" could be due to an interlaced video mode being used. I'm just guessing here, but it might be the monitor is running at 512x512, which is "flickery" on my Betson because it's an interlaced video mode (the monitor draws the even lines first, then the odd). Try experimenting with some other resolution settings for Pac-Man and enable/disable hardware stretch, if the flickering drives you nuts.
--- End quote ---
This has raised even more questions for me. I turned on hardware stretch which made the screen more blurry, but it also helped the shaking. When I let Mame choose the resolution the Betson reports that it's running at "15.9KHz 51Hz" when you go into the OSD. Is there a way to get the monitor to tell you what resolution it's actually running at? The Pacman info screen says that it should run at "288x224 60.606060 Hz".
If I manually specify the resolution on the command line to be "288x224" Pacman comes up in a different resolution than when Mame auto-picks the resolution. Betson reports that this manual resolution is running at "37.8 KHz 60Hz". In this resolution there is very little flicker. Is Mame auto choosing the wrong resolution? Is there a way to fix this short of creating a ini file for each game?
Lastly, when Pacman came up in "37.8 KHz 60Hz" mode I had to tweak the pincushion and vertical positioning settings in the Betson's OSD. When I went back to my Windows desktop (which runs at 800x600) I found that I had changed its settings too. This is how I found out that "37.8 KHz 60Hz" is used by both 288x224 and 800x600. Do I have any other options other than either living with one of the resolutions being messed up, or manually changing the OSD settings each time I switch between these resolutions? I assume that the Betson saves its customized settings per frequency (for example "37.8 KHz 60Hz" and "15.9KHz 51Hz") instead of resolution (288x224, 800x600, etc.).
Thanks for all of your help,
Jim