Quote:
Originally Posted by
bootymonger 
Just to experiment, I entered the substitute zip in my analog OTA TVGOS Panasonic E85H and so far nothing has changed (but this might happen over night, and since I've never changed the zip I don't know how long this normally takes or if I have to do something to force a redownload of the guide data). I doubt the DTVPal will magically feed analog TVGOS devices (is this even theoretically possible over an RCA connection if you don't use the RF cable??), but it would be nifty if it did.
TVGOS systems are present in both analog and digital devices, with the data coming from analog PBS stations, presently, as you probably know.
The section of the DTVPal manual on TVGOS is pretty clear that it is intended to provide continuity of service for analog devices. Their description makes it appear that they will do this by doing a couple of things...
First they have to create a way for the TVGOS devices that are designed to get their data ONLY from an analog station to actually get the data from the digital (CBS) stations that will be carrying them. For many moons the talk (for example on threads for high-def digital receiver/recorders, such as I have) has been that a cecb could receive the digital signal, convert the AV stream to be output as an analog signal, and at the same time take the associated TVGOS data and convert it to the same form that the closed-caption data is being converted. Apparently the DTVPal is designed EITHER to do this for the whole TVGOS data set OR to make up a restricted OTA data set for use in the analog devices. (The full set also contains data on cable channels.) The TVGOS device would then pick out the program info for the zip code it's in. The DTVPal manual tells analog device owners to reset their devices by entering a new fake zip code for each major metro area, so that it will look for TVGOS data for the area's OTA channels given with fake analog channel numbers, because these devices can't deal with channel numbers like 9-1 (a digital channel number). By the way, the TVGOS devices are designed to scan the analog channels until they find one that has the data, and to return to that one each early AM to get updated data. If it finds that it can no longer get that station or that the original one is no longer carrying the data, it will scan again to find a channel that carries the data.
The other thing that the DTVPAL does it provides feedback from the TVGOS device, probably to do the scanning above, but also so that the viewer looking at the TVGOS device can choose what channel to watch or record, which info goes out the g-link to tell the DTVPal to change channels...
As for where this altered TVGOS data comes from, one possibility is that the DTVPal creates it on the basis of the TVGOS data it is getting from the digital station. The OTHER possibility is that Gemstar (the source of the TVGOS data that goes to CBS and then over the air) will actually INCLUDE this data set as part of the much bigger set being broadcast (which would have data for all the ACTUAL zip codes in a metropolitan area), and entering the fake zip code just instructs the TVGOS device to look for that data set in particular. This would then entail the DTVpal simply translating the TVGOS data set, rather than making up a new set with a fake zip code and fake channel numbers.
I have to admit that many of us hope that the second possibility is the right one. Then - for DIGITAL devices that are not designed to look at digital stations for the TVGOS data - the DTVPal would serve the purpose, without our doing the zip code change or making the feedback connection. All these devices need is for the full TVGOS data set to be translated to a converted analog channel, which can be joined up with the full antenna signal, and they will have the program data they need, as well as the digital broadcast stations (plus whatever people have from cable), and the devices keep working as designed...
But, as I say, the manual is pretty clear about what the DTVPal is supposed to do for the analog TVGOS devices, but it's doesn't say (and why should it?) exactly where the data set for the fake zip code comes from...
Someone in one of the threads has - over the months - been told by someone at Gemstar that the "TR-40" works for converting the TVGOS data, but it isn't clear to me exactly what that means, as indicated above.