The amazon link you posted is just a GBS arcade scaler. It does not accept TTL RGB from a real CGA/EGA card

Thanks and good point ! the manual for it does list: CGA/EGA input signal auto scan (15K, 24K, 31KHz), but does not mention TTL. It does tell you how to connect a 9pin CGA/EGA cable to the inputs.... might have to call/email to see if really supports old school TTL EGA input. So is the 8219 also just an upgraded arcade scaler too ? It's manual does not list TTL either. I can build a TTL to analog converter as long as the box does double the H sync for VGA out.

I would get the mce2vga : https://www.serdashop.com/MCE2VGA
This was made specifically for pc signals, just plug in and it works.
In arcade world cga means low resolution 15khz signal and ega means 25khz signal... No idea why they are named like that but they are not pc standard signals.

In case you are using the monitor for PCs and you don't need to explore some undocumented features of CGA/EGA cards I do recommend you to use an industry standard for decades VGA card(s) instead of a converter. The image is better than that of CGA or external converters. The refresh/response is natural and does not pass secondary (out of clock) digital processing of converters. These converters are valuable when non-standard (non PC) computers/consoles. A VGA is native and much cheaper option designed by IBM and enhanced by many 3rd party engineering companies and produced and used in hundreds of millions pcs until present time. The converters are hobbyists' projects...

georgel wrote:

In case you are using the monitor for PCs and you don't need to explore some undocumented features of CGA/EGA cards I do recommend you to use an industry standard for decades VGA card(s) instead of a converter. The image is better than that of CGA or external converters. The refresh/response is natural and does not pass secondary (out of clock) digital processing of converters. These converters are valuable when non-standard (non PC) computers/consoles. A VGA is native and much cheaper option designed by IBM and enhanced by many 3rd party engineering companies and produced and used in hundreds of millions pcs until present time. The converters are hobbyists' projects...

Indeed. And what is anyone messing around with >30 year old hardware for fun, not profit? Very much a hobbyist.

In any event VGA doesn't do a great job of backwards compatibility with CGA, particularly not with those titles that pushed the limits of the standard for better results than white/cyan/magenta/black or red/green/orange/black. Not all systems with CGA/EGA have the option to upgrade to VGA, and even where it is possible, someone might want to keep their ancient hardware in original state rather than adding a totally period-incorrect display adapter.

Have you even seen the MCE2VGA adapter? I second Keropi's recommendation. 'It just works', looks great and lets you run old stuff exactly as intended. Moreover compared to the price of a working TTL monitor or indeed an 8b VGA card, it's very good value. And it lets you use that 'industry standard' monitor you apparently so love.

georgel wrote:

...

I believe OP said he just wanted to have a converter so he could test machines on the bench before going and digging through VGA cards or buying one for a machine that might not work.

Many vintage computers come with MDA/CGA/EGA boards already installed, and 8-bit friendly VGA cards can be expensive or hard to find. Sometimes it is in your best interest to just get a cheap converter until you can make sure everything else in the machine works before trying to shoehorn a much later video card into an old machine.

It's the same case for me, except I just decided to go out and buy MDA/CGA/EGA monitors for cheap on eBay and use those instead. $70 shipped and now I've got a couple on the bench.

I recently bought an Extron RGB 202xi, I haven't tested it yet because I'm still trying to get the smokers smell and gunk out... but according to the manual it should pretty much eat anything from MDA, CGA, EGA and convert it to RGBHV

imi wrote:

I recently bought an Extron RGB 202xi, I haven't tested it yet because I'm still trying to get the smokers smell and gunk out... but according to the manual it should pretty much eat anything from MDA, CGA, EGA and convert it to RGBHV

That should work great, but remember it's just an RGB interface, not a scaler. Your RGBHV display or capture device will still need to support 15kHz and/or 22kHz to work with EGA

yep, I know I also have among others an Extron USP405 up/down scaler and scanconverter 😉

these old devices are quite handy when dealing with all kinds of different signals.

imi wrote:

yep, I know I also have among others an Extron USP405 up/down scaler and scanconverter 😉

these old devices are quite handy when dealing with all kinds of different signals.

I would actually recommend pairing it with a GBS scaler like the one linked earlier in this thread (but ffs don't pay that much!) if you need 31kHz output - BUT you've got to try out the custom firmware for the thing, stock sucks.

https://github.com/ramapcsx2/gbs-control/wiki … ld-the-Hardware

There's a huge thread on the shmups forum about the CFW too, the current developer isn't the OP so it's a bit confusing to navigate if you're just jumping in, but user "rama" is the one now maintaining the project.

yeah I plan to get one of those to play around with too, the main reason I got the extron is so I can display 31+kHz signals on a 15Khz monitor and just as a general purpose device because it converts basically any analog signal up or down.

FAMICOMASTER wrote:

georgel wrote:

...

Many vintage computers come with MDA/CGA/EGA boards already installed, and 8-bit friendly VGA cards can be expensive or hard to find. Sometimes it is in your best interest to just get a cheap converter until you can make sure everything else in the machine works before trying to shoehorn a much later video card into an old machine..

8-bit compatible vga cards aren't hard to locate. You don't have to shoehorn anything. They fit without much bother at all. There's a thread over at vcfed.org on this very topic, modem7 also has a listing on his web site http://www.minuszerodegrees.net/5150/vga/5150_vga.htm and Monotech PC sells 8-bit Trident TVGA9000 based cards brand new https://monotech.fwscart.com/XT-SVGA_-_8-bit_ … 4_19697623.aspx based on sergeys work http://www.malinov.com/Home/sergeys-projects/isa-supervga Certainly cheaper than getting a few monitors at $70 a pop and taking up space.

If my EGA monitor ever dies and cost a mint to fix I'm definitely going to install a vga card in the XT Turbo I have. Just flip the lid up, pull the old video card out and fit the vga card. Then close the lid. Easy as that....

There's also this little guy if you don't want to track down an older Extron RGB interface with TTL support

https://gglabs.us/node/2063

Thanks everyone ! I think the MCE2VGA may be my best alternative. Testing some older non-VGA stuff is going to be a problem very soon for me and need a simple easy to move around fix. One of the many cards I need to test is an old 1986 era GRX Legacy II which I can find no real good doc's on and prefer not to gamble on trying diff monitors on. Any other suggestions for a cga/mda/ega to vga converter gladly accepted.

MonoTech PC has this https://monotech.fwscart.com/EternalCRT_-_MDA … 4_19478791.aspx

IMO, a scaler is a super handy thing to have around anyway. If you have one use for it, you have a dozen, easy. I've got a StarTech video-to-VGA scaler for cheap and cheerful bench composite, S-Video, component, and RGsB sources; a RetroTink 2x for most of the same to HDMI; and two OSSCs -- one for SCART / YPbPr, and one for RGBHV. They've all come in handy for so much more than I originally intended. Highly recommended.

The TTL-to-RGB conversion is fairly simple. I've had a board design for months that I've just been too lazy to check and send off to fab. Maybe this weekend... Would be nice to get the PCjr and Tandy 1000 running.

Caluser2000 wrote:

MonoTech PC has this https://monotech.fwscart.com/EternalCRT_-_MDA … 4_19478791.aspx

I love monotech! I had no idea they offered this kind of device. I think I know what I am getting for christmas 😁

mothergoose729 wrote:

Caluser2000 wrote:

MonoTech PC has this https://monotech.fwscart.com/EternalCRT_-_MDA … 4_19478791.aspx

I love monotech! I had no idea they offered this kind of device. I think I know what I am getting for christmas 😁

Some of the astablished players have an issue with JD and co. So much so I got banned from #vc for providing a few home truths. A glitch in the matrix as it were. Apparently competition is a bad thing.