Radio3787 said:
Is PSIP a concept/technology that is only temporary to help the DTV transition? Or do stations plan on keeping their virtual channel and actual channel different indefinitely?
It seems to me, 10 years from now, having a station tell viewers they're on one channel when they're actually broadcasting on another just doesn't make sense. With the station's OTA channel, their PSIP channel, and their cable channel... That's a lot of different numbers!
To nitpick a bit, PSIP is a rather inclusive technology of which virtual channels are a small part. PSIP is also responsible for the program guide, and for grouping the datastreams that go with each subchannel. Among other things. Without it, your TV wouldn't know which video and audio streams go with 4-1 NBC and which go with 4-2 Telemundo. Without PSIP DTV simply won't work.
But obviously you were asking about the virtual-channel provisions. IMHO they will be around forever.
I answer viewer emails (at least 3-4 a day, plus an occasional phone call) about DTV reception issues at the most popular station in Nashville.
NO regular viewer has ever expressed confusion over virtual channels. It simply isn't on their radar. The only places I see concerns over remapping is on forums like this one, where technically-oriented people meet.
Look at it this way.
There is no such physical concept as "channel 4". Does it mean TV channel 4? Or CB channel 4? Or marine radio channel 4? Or the 4th channel programmed into the officers' handheld radios by the Metro Police Department Radio Shop?
WSMV-TV broadcasts on 67.25MHz. Your TV contains an internal lookup table; when you punch in "04" on the remote, it checks that table, and tunes to 67.25MHz. Assuming you're within range of Nashville... it finds WSMV there, and displays our program.
WSMV's digital signal is broadcast on 192.31MHz. Your digital TV contains an internal lookup table; when you punch in "04" on the remote, it checks that table, and tunes to 192.31MHz. Assuming you're within range of Nashville... it finds WSMV-DT there, and displays our program.
The only difference... The analog lookup table is pre-loaded at the factory. The digital lookup table is loaded when you scan for channels. Since even analog TVs have demanded you scan for channels when you first turn them on, there really is no difference as far as the ordinary viewer is concerned.
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Now, let's look at the situation where there was no virtual-channel table. Let's consider the Los Angeles market.
Without remapping... when you buy a digital TV, EVERY station moves to a different channel.
In June, when the analogs go off, nine stations will move again -- will go
back to their old channels. That includes five of the seven most popular stations.
Channel 9 has become channel 43 - but will become 9 again in June. Channel 2 has become channel 60 - and will become channel 43 in June. Channel 43 -- is it CBS? Or is it K-Cal? Likewise with channel 35 -- is it KMEX in Spanish? Or KRCA in Korean?
I'm sorry, but it's FAR simpler to use remapping and let every station stay where it is. It'll confuse the techies but there aren't enough of us to put a dent in the ratings. (especially because those of us who work in the business can't have a ratings book anyway...)