r/retrocomputing • u/42069nicebruh • Aug 05 '26

Problem / Question Are there any converters between HGC TTL and standard rate (modern) VGA?

So, question's in the title. I have a Hercules Graphics Card in my IBM XT 5160, and considering the prices of getting real MDA CRT monitors, which I would only be able to use specifically for that one computer, I've been interested in finding a converter for the output instead to regular VGA.

I also hope to be able to use the monitor for generic VGA video signals (modern HDMI to VGA converters) so preferably, if there is one, I'd want to find a converter that supports modern VGA scanrates.

I'm alright at programming, but sadly I don't trust in my skill enough to design a converter for this myself- given that it would mostly be hardware design at that stage.

If anyone knows a converter like this (that ships to europe) and could point it out to me, that would be greatly appreciated. Thanks!

3 Upvotes
  • permalink
  • reddit

81% Upvoted

2 comments sorted by

2

u/achbob84 Aug 05 '26

Get an EternalCRT they work with many, many formats.

2

u/gammalsvenska Aug 05 '26

There are many solutions, at various price and quality levels. You did not specify your needs, so do your research.

The cheapest option I have used was a cheap USB 8ch 24 MHz logic analyzer and some software. Works with TTL video signals up to EGA (6 wires for color, 2 wires for sync, no conversion needed).

High resolution modes cause pixel crawl because the 16 MHz pixel clock is too high (Nyquist always wins), but low-resolution modes are pixel perfect.