I've been trying to demystify the RGB port on my RCA Colortrak 2000. Very little information is available online for these televisions, however earlier today I happened upon a training manual from RCA on the CTC-131 chassis. According to the manual the RGB input is 80 column TTL. From what I gather, RGB mode is enabled by switching to AUX 3 (Ch 93) and connecting something to the Green port. Nothing much is said about the "Enable" port, so my guess is that a possible RGB OSD overlay may be possible while not in AUX 3 by putting 5V to the enable port??? (Someone more familiar with reading these TTL diagrams may be able to provide an opinion on that.) The other thing I am wondering now is what could this port be used for? If I were to connect my IBM 5160 CGA PC to this I would lose out on 8 colors due to no intensity port. This also has a Composite Sync with what I believe a max of 1V which wouldn't be compatible with the PC either. Does anyone know what device would be able make use of this port? The other question would be if I could convert this to Analog RGB by bypassing the TTL circuitry and connecting directly to the U700 IC. Looking forward to hearing some opinions from people more knowlegable than I. Thank you in advance.
i came into possession of this model tv a bit back, and have been attempting to find information such as the OP posted. however, I'm still lacking some clarity. I've seen it mentioned that this would accept CGA signals (minus intensity? or is that Enable jack used?) . the schematics and stuff don't seem to mention this information. unfortunately, information is quite scarce. any information would be very much appreciated!
i came into possession of this model tv a bit back, and have been attempting to find information such as the OP posted. however, I'm still lacking some clarity. I've seen it mentioned that this would accept CGA signals (minus intensity? or is that Enable jack used?) . the schematics and stuff don't seem to mention this information. unfortunately, information is quite scarce. any information would be very much appreciated!
From what I recall, it's standard CGA with an intensity bit (RGBI) and not analog RGB. I'm pretty darn sure that's the case, but I can't give you a 100% without finding the post. You could probably post there as well and ask. Someone might be able to tell you.
It looks a digital video input for old computers. It's non-trivial to convert this to an analog input RGB input if there is no RGB video clamp circuit present (you would have to make one).
I’m pretty sure the RGB was intended for Teletext - which never really took if in America - and I would imagine the Teletext decoder probably came with a cable / cables to connect to the RCAs.
Really interested to see someone take a deep dive into one of these things
