Why does WPXA 14 keep screwing around with odd sub channell numbers?

[Mattswad]

As if it's not odd enough that WPXA (Ion/qubo/IonLife) choose to broadcast on 51.3/51.4/51.5 for their virtual channels 14.1/14.2/14.3, my converter box keeps getting these strange channels that they apparently have been experimenting with.

I know someone mentioned this before either here or on the AVS forum last year, but as of tonight, the following channels have aired some type of receivable content from WPXA:

51.3-ION (Channel 14.1)
51.4-qubo (Channel 14.2)
51.5-ION Life (Channel 14.3)
51.100- ???
51.101- ???
51.200- ???
51.209- ???
51.300- ???
51.301- ???
51.302- ???

Why are they doing that? I guess would be the general synopsis of my post.

 

[w9wi]

It comes in *only* on 51.3 through 51.5?

On many receivers it would be normal for a station on 14.1/14.2/14.3 to *also* come in on 51.3/51.4/51.5.

14.1/14.2/14.3 are established by a "virtual channel table" (VCT) transmitted by the station. This tells your receiver how to relate a physical frequency (in this case 692.31MHz) to a channel number -- what frequency to tune to when the viewer punches in "14".

Some stations have been known to screw up & fail to transmit this VCT. A receiver built strictly to the ATSC standard wouldn't be able to receive such a station. However, most receivers assemble what you might call a "fake VCT" for a station that isn't transmitting one. It uses the "major channel number" (the part before the decimal) derived from what the station's frequency was called in the analog era -- in this case, 51 -- and the "minor channel number" (the .3 part after the decimal) obtained from the "program number" transmitted in the station's Program Map Table.*

That's where the 51.3/51.4/51.5 thing comes from.

And indeed, I've found many receivers will assemble this "fake VCT" even if the station is transmitting a proper VCT. You can tune stations *either way*. Try it with WAGA: try tuning not 5.1, but 27.3. I'm betting you'll find most receivers can tune WAGA either way.

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As for 51.100 through 51.302... https://houstondtv.wordpress.com/2012/03/26/airbox-packages-announced/

It's a "wireless cable" kind of thing, $10/mo. for five channels and another $10 for Starz. There's also mention of pay-per-views which I suppose explains why you're seeing seven channels. They're using encrypted MPEG-4 which is why you can't decode those. (I'm hearing mixed reports as to whether the audio works on a regular TV)

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* I suppose it's possible for some stations to screw up & not transmit a Program Map Table. On such a station your receiver wouldn't have a way of knowing which audio stream went with which video stream -- in the end, you simply won't be able to receive a station without a PMT.

 

[gregg75]

Matt you and your uncle are the only ones watching ION anyway ;D.

But I get the same thing with WPBA. It comes in on 30.2 for some reason in my house.

 

[kilamanjero]

Matt you and your uncle are the only ones watching ION anyway ;D.

But I get the same thing with WPBA. It comes in on 30.2 for some reason in my house.

Wrong! You would be surprised who will watch Ion...

 

[Markxxx]

Aren't some of the ION experimenting with a service using mp4 subchannels that will bring Spanish TV in over their main channel?

 

[dhett]

Ion is offering an 8-subchannel service called Airbox, although as far as I know, it has only been rolled out to the public in Houston. The Airbox lineup typically includes the Starz movie channel, the NFL Network, a barker channel and Spanish-language nets Gol TV, ¡Sorpresa!, Telefórmula, Pasiones and CineMex.

The channels use MPEG-4 encoding; several players handle MPEG-4 well, eg., VLC Media Player and DeContiis.

Last November, when my Ion station, KPPX Phoenix, first added the Airbox service (I saw Airbox on WPXA Rome last July, earlier than most), they ran the barker channel in the clear. They aired the UFC 139 MMA match on the channel, which I transfered to my TV via wireless connection. Picture quality was pretty good, although in 4:3 ratio, and there were no problems with the sound at all.