So... would this have been feasible today? given the bandwidth required to send a full feed these days, i suspect likely not, eh? (even if you were able to do it on all 500+ channels in parallel)
On the financial side, it is trivial.
The opposite, the bits were paid for but unused back then so financially it was worth using them. In digital tv every bit has a use and so a cost, hence they are used for more TV channels instead for parasitic services. You end up competing with TV if you want any quantity so hard to make viable today.
On the engineering side, _impossible_.
The opposite, completely trivial now. Digital TV is a mux of a number of bit streams, some with compressed video others with meta data for epg, alternate sound, interactive apps etc. Adding another stream to the mux is trivial, you just have to pay for the bandwidth though as most are stat muxed it's possible to create room at the expense of the vbr streams where the video encoders reduce the quality of as result of back pressure from the stat muxer
To pick a conservative number, say you get an effective throughput of 2k bytes/sec
It'd be easy to squeeze that into a normal tv satellite mux
As I understand it, a current USENET 'full feed', including binaries, take two dedicated 100mbit FDX fast ethernet links, and they are saturated _most_ of the day. At that rate, A full day of TV vertical interval transmission wuould handle under _ten_seconds_ worth of the inbound traffic. You would around =ten=thousand= analog TV channels to handle a contemporary 'full feed'.
Or just 3 full muxes at cost of around 10M (probably the same in any currency) per year brandon