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Hi Jeff,

Hi Jeff,
I am asking around a bit for you.  Meanwhile what kind of VGA convertor do you have?  I assume there are not any parameters that can be changed on it?
Bil

VGA monitor

Thanks for looking. I actually have 2 that I have tried both with different results. Hope you don't mind a link but I think it would be easier to see the specs of each.
1. http://www.amazon.com/gp/product/B0095DAPY4/ref=oh_details_o01_s00_i00?ie=UTF8&psc=1
This one is the unit I described in my first post. The top inch of screen seems to shift and twitch by a half inch. Almost like its bending the picture.
2. http://www.a2dcorp.us/pdf/marshall/MC-0105.pdf
This one is the second one I bought. The whole screen has issues with artifacts around the edge and just generally a flickery picture. Both are being fed by a s-video cable like the ones you can buy on eBay. I checked and the shield on the cable is properly grounded and it works well on a regular ldc tv set. The monitors I am using are a standard Lenovo/IBM unit and a base Dell monitor. The picture is somewhat better on the Lenovo/IBM in regards to the flicker but the text and colors even though jumpy are better on the Dell unit.
I am having these issues on both my C64 and C128 so I assume that this eliminates a bad video output from the computer.
Thanks again for the help! It's awesome that there are still so many people into these machines, it would be amazing to see what would be produced if Commodore was still in business. I think that the computer landscape would be quite different (and probably in an amazing way.)

The first symptom sounds like

The first symptom sounds like what we used to call "flagging", and could be seen on VCR's where the TV set had a manual Horizontal Hold... basically the horizontal looses sync during  the vertical sync time and it takes several lines to get back on frequency.

So guess where the C64's video non-compliance is?  (yup, total lines and the vertical sync)
A really good device might bring it back, as a engineer I have designed run from start type timing where it essential resets during vertical sync and then pumps out one frame at the right frequency. (no phase lock loop)
I would have said that I'd be surprised if VGA could be driven by a VIC chip in any shape or form except that the market has had 20 years to figure out how to do it.
Let me see what I can dig up.
 
Bil

Re: New user/ vga monitor question

FWIW, there has not been a comprehensive study on which is the best composite or s-video-to-VGA converter. Some are very cheap -- under $20 -- to those that are hundreds of dollars -- around $400 -- to those that cost thousands of dollars! The multi-hundred dollar video converters are a big interest to those pinball machine fanatics. The multi-thousand dollar video converters are a big interest to those in the professional video industry. When I see my gamer friend at next month's TOGA meeting, I will again ask him the names of those multi-hundred and multi-thousand dollar video converters.

Truly,
Robert Bernardo
Fresno Commodore User Group
http://videocam.net.au/fcug
The Other Group of Amigoids
http://www.calweb.com/~rabel1/
Southern California Commodore & Amiga Network
http://www.sccaners.org

*Update*

Interesting update on the whole VGA issue. Tried a new Commodore-S-Video cable bought off eBay combined with the Lenovo monitor and the artifacting has gone away. Commodore boot screens on both the 128 (in both 64 and 128  modes) and the standard 64 unit I have look amazing. Now if I run GEOS the text for the different apps is somewhat blurry. Not bad just not crisp and clean, the problem is even worse when the text is not in black. Blues and reds seem to blur worse than solid black. I have heard about the resistor fix for the chroma line and probably will test one out to see the difference as the cable does not have one in it from the manufacturer. I will try and get some before and after pictures of the screen but from everything I have read this is most likely the fix. Not sure the issue with the first cable, I am assuming poor shielding or something of that nature but the new one works amazing!

Re: *Update*

Jeff Stringham wrote:

> Tried a new Commodore-S-Video cable bought off eBay combined with the Lenovo monitor and the artifacting has gone away...

Who was your seller on eBay?

Truly,
Robert Bernardo
Fresno Commodore User Group
http://videocam.net.au/fcug
The Other Group of Amigoids
http://www.calweb.com/~rabel1/
Southern California Commodore and Amiga Network
http://www.sccaners.org

the seller goes by the name

the seller goes by the name "aaascrapdogsunlimited" they are out of Texas. Seems to be a well made cable, better than anything else I have found. Looking like the issue with the old one is that the wiring was not soldered well where as the new one is potted in the connector so hoopefully it will make it stronger. 

Re: *Update*

Jeff Stringham wrote:

> the seller goes by the name "aaascrapdogsunlimited" they are out of Texas. Seems to be a well made cable, better than anything else I have found.

Thanks. Good to know.

And a name not easily forgotten,
Robert Bernardo
Fresno Commodore User Group
http://videocam.net.au/fcug
The Other Group of Amigoids
http://www.calweb.com/~rabel1/
Southern California Commodore & Amiga Network
http://www.sccaners.org

Hi Jeff

Hi Jeff
Also I asked around and the general consensus is that some work and some don't and you have to try it to be sure.  Several mentioned getting them off EBay, I assume they meant that the seller had tried in on a C64, or maybe they were just low priced. One person gave me more detail that I will email you with rather then post someone else's word here.
 
Bil

Thanks

Thanks! I look forward to reading it!

Finally a solution

Finally got a solution for this vexing problem! Using the above mentioned s-video cable and a Mygica HD game box I have been able to connect my C64, C128 and my C128D to a VGA monitor with a near perfect picture. I will have to post pictures as soon as I get a chance. Thanks for all the helpful insight in getting this resolved!

Re: Finally a solution

Jeff Stringham wrote:

> Using the above mentioned s-video cable and a Mygica HD game box I have been able to connect my C64, C128 and my C128D to a VGA monitor with a near perfect picture.

How exact are the colors when compared to the colors displayed from a Commodore monitor?

Truly,
Robert Bernardo
Fresno Commodore User Group
http://videocam.net.au/fcug

Pictures

Finally got a chance to take some pictures of the monitor setup I am using. The C128D looks great although I am using a cheapo Dell monitor that doesn't really do the picture justice and for the C64 I am using an IBM/Lenovo screen that is by far the better one. From what I remember these look pretty similar to an actual CRT screen and there does not seem to be much degrading of the picture. Excuse the mess on my desk, its been a hectic week with final exams and finishing up the semester, haven't had much time to keep things clean.
Link for pictures:
http://c128d.imgur.com/

Re: Pictures

Looks good! Do you see any noticeable lag in fast-moving images?

Happy Thanksgiving!
Robert Bernardo
Fresno Commodore User Group
http://videocam.net.au/fcug
The Other Group of Amigoids
http://www.calweb.com/~rabel1/
Southern California Commodore & Amiga Network
http://www.sccaners.org

pictures

Surprisingly not! The converter box seems to do a good job keeping up with the images and I have not noticed any lag or ghosting of the picture. Only issue I have noticed is that some of my older C64's produce a slightly grainer image but the newer ones have no issues. Seeing as this box is ~$35 I am very surprised in the image quality, better and some of the other more expenseve ones I have tried. I wish I had some sort of benchmark program that would allow me to run some graphics to see what the limit this box can do. That would probably be the best method over my personal opinion but so far so good from what I have expereinced with this converter

I must say, thats a pretty

I must say, thats a pretty good picture when you also consider upscaling etc. Are you using the composite signal or the svideo?
 
 
 

Picture

Yeah I agree it does look good. I was shocked that a $30 box of Amazon provided better picture than anything else I had tried. Those pictures are using the s-video connector, I have tried the composite and while it works fine I just defaulted to s-vid. There is a little degredation in the composite on my cheaper monitor but nothing on the better one.

Wow that is a really clean

Wow that is a really clean setup you have there.  Almost looks like you could do your homework on it... welll thats what we told our parents when we really wanted to play games.
 
What was the make/modle of the convertor  that you used from Amazon?
 
Bil

Converter model

The  converter is a "Mygica HD game box Video to VGA converter/switcher" The actual model is "HDGameBox" according to Amazon. For $30 it far surpased my expectations and seems to be durable. I actually did a homework paper on it, all 12 pages in GeoWrite, think I confused my professor :)

Re: Converter model

Yeah... GEOWrite! By the way, you should complete your Commodore set-up with a Commodore VGA monitor. :)

A 1942 or a 1960 would do,
Robert Bernardo
Fresno Commodore User Group
http://videocam.net.au/fcug

speaking of VGA, could one of

speaking of VGA, could one of the converter allow you to do pixel splitting? where you feed the individual color channels along with the H/V syncs into three different monitors driving only the green channel on each.
 
a cheap hack for a three headed display.

that sounds like a custom job

that sounds like a custom job to me.

a splitter cable, maybe some

a splitter cable, maybe some drivers to boost the TTL H/V signals. as for the software I would be lost. If only there were an easy way to address the memory for each of the colors.

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