And used ("FIRST USE: 19810923", "FIRST USE IN COMMERCE: 19811109") as early as September 1981, so that seems to sync perfectly with what the SEC report says.AriX wrote:As further evidence to swest's finding that the EPG channel was started way before 1985, check out trademark serial number 73398017 for the Electronic Program Guide (and logo). It was filed in 1982.
@LH - Yes, that looks like exactly the same thing. I wonder if the failure of the video overlays to appear has anything to do with why they were pressing Ctrl-U? (Like, if they were pressing it in response to that, is what would be an interesting piece of information.)
About the two different Sneak Prevues, I did have it at one point on my old cable system, but don't know which it was and can't offer specific information on it (other than things learned on the net) because I had nil to do with it with UV.
And about EPG/PG's VBI data, all I could tell from looking at WGN's VBI way back when -- and not with a frequency monitor but with a proc amp that simply let me to roll it onto the screen for visual inspection -- was that it had lots of data in it. Because I knew their VBI "fed Prevue Guide," I assumed the bulk of it was UV's. Now that it appears UV used a dedicated data subcarrier for "text" (which I assume was that satellite list's author's word for "listings"), and mindful of those EPG Data vs. Control Data traces on the VBI decoder card, I'm thinking the VBI must have possibly only been for the "control" data (think separate data channel for anything that needs to be communicated instantly, so it won't end up being delayed by a traffic jam on the 2400 baud feed).
Re: "data transmitted as an audio feed too", technically this 7.237 MHz subcarrier I'm talking about was both. Data as audio... just like a dial-up modem on a phone line. So in total, it looks like the satellite decoder card may have watched two sources: WGN's VBI and 7.237 MHz (or for non-EPG boxes, PG's VBI and maybe 7.237 MHz there too).
@edit - It is also entirely possible that this 7.237 MHz subcarrier was only used with the pre-1985 units. Really, unless more information can be found, it's probably pointless for me to have speculated above as far as I did. I just know there was VBI data from 1985 onwards, and (thanks to this PDF) that there was an audio data feed before it.
