In the 1980s and 1990s, there were many computers made that used a 15Khz analog RGB signal. These included the CoCo 3, Commodore Amiga, Atari ST, etc. There were a number of monitors to choose from to use on the CoCo 3, with one of the most popular being the Magnovox (remember them?) 8CM515. It supported RGB-A but also had composite audio/video so you could get the old CoCo 1/2 artifact colors when needed.
I thought the days of 15Khz was long gone. We have had a few solutions for hooking up a monitor to the CoCo 3, including an FPGA project, Cloud-9’s VGA converter, and the Switch-a-roo cable with a SCART converter box.
But Alexandre Souza on Facebook let me know they use all kinds of LCD monitors in Brazil, and pointed me to this list of modern monitors that still support 15Khz analog RGB:
One of the highly recommended monitors on the list is on Amazon for $139. It might take just as a cable to make it work with the CoCo, or possibly a bit of signal inversion (just like the old days).
Anyone know more on this?