What causes OTA channels to appear on the incorrect channel number?

[CubsWin]

Can anyone explain why some of the channels on my old TV's OTA tuner appear on the incorrect channel number?

For example, WFLD Chicago should be on channel 32.1, but my old TV shows it on 31.1 instead. All my other OTA devices in the house have it correctly on 32.1. There are several other examples of channels that are on the wrong frequencies, but not all of them are wrong.

Is this just a case of an old OTA tuner that maybe can't handle certain newer channel mappings, or is it something else entirely?

http://www.rabbitears.info/market.php?request=print_market&mktid=3

 

[FaT Air]

Because they actually transmit on channel 31. Their "Virtual' (NOT REAL) channel is 32. I've noticed this once when I had a weak signal on one 'set' (Television for the young whipper snappers)
OR - Maybe that 'old' set disregards the, not real, virtual channel numbering(?)
http://rabbitears.info/market.php?request=station_search&callsign=WFLD
Virtual = Display Actual = Physical

 

[Mr Tony]

Is this just a case of an old OTA tuner that maybe can't handle certain newer channel mappings, or is it something else entirely?

the bolded part. How old is the TV?
My grandma has a HDTV that is probably 8 or 9 years old. When they moved into their assisted living facility a year and a half ago they had to wait a few days for them to set up the "cable". So I hooked up a antenna for like 3 days and for some reason her TV did the same thing. It logged WCCO (which is 4-1) as 32-1 which is its REAL station. It was hard to convince grandma to watch CBS was to hit 32 (it automatically went to 32-1). But then when she had cable CBS was channel 433 or something goofy

The only other reason is what FaT Air noted and that was a weak signal. When I was DX''ing last summer I locked the NBC in Rhinelander/Wausau Wisconsin (which is PSIP 12) but it logged as 16.3 & 16.4 which is their actual station.

 

[FaT Air]

I got one now that, well let me first say what the Real and virtual channels are.
real - virtual
38 - 4
6 - 8
10 - 10
44 - 11
15 - 2
16 - 16
TV is programmed and goes Up/Down sia the virtual ch #'s via the remote.
Ok, I hit just the 8 on the remote, tv goes to 8-1
I hit 10 and the tv goes to 10-1
I hit 4 and the tv goes to 2.1
I hit just 11 and the tv goes to 2-1
I hit 38 and the tv goes to 4-1
I hit 44 and the tv goes to 11-1
2 numbers entered = REAL Channel
2 numbers entered, then a dash, then a digit or two more = Virtual channel
So to go to ch 11-1 you can enter the virtual. 4 keys pressed, OR 44, with only 2 keys pressed.
Why did they make it so complicated with these 'virtual' channel numbering scheme any way??
I don't think 'so they could use their "OLD identity"' necessary if they are now broadcasting on a 'new' channel.
A small effort to let the people know what 'new' channel they're on was all that was necessary.
As is, Now, it's bordering on ridiculous. IMHO
It sure didn't make them easier to find. I know of an elderly couple (and their late 20's to 30 something daughter) that couldn't understand why, when they punched in 11, there was nothing but a blue screen with 'No Signal'. How were they to know that it HAD to be programmed or they should have punched in 44 ?
I punched in 44 and BANG, the TV programmed in the channel as 11-1 thru 11.3. (I wasn't going to sit around for an extra 20 minutes watching the programming progress bar) BUT I left them with the knowledge that from now on if they want to go directly from channel whatever to ch 11-x, they'd have to punch ONE, ONE, Dash, ONE or Four, Four, for the news. Are they confused yet? You bet!

 

[Mr Tony]

all depends on the TV.
My Panny plasma I can hit 11 enter and it goes to 11-1 or 4 and it goes to 4-1
Even better the dash isnt needed in most cases. I can push 53 and it goes to 5-3 since its already programmed in

My AOC TV if I hit 11 it goes to 11-0 which would be analog 11 (not digital)
Havent tried it on my new Toshiba TV yet

 

[FaT Air]

all depends on the TV.

Doesn't that make it even more confusing? Different behavior for different TV's. Not many people have the same brand, year and model, throughout the house. Kitchen bedroom and living room.

Why did they make it so complicated with these 'virtual' channel numbering scheme any way??
I don't think 'so they could use their "OLD identity"' necessary if they are now broadcasting on a 'new' channel.
A small effort to let the people know what 'new' channel they're on was all that was necessary.
As is, Now, it's bordering on ridiculous. IMHO
It sure didn't make them easier to find. I know of an elderly couple (and their late 20's to 30 something daughter) that couldn't understand why, when they punched in 11, there was nothing but a blue screen with 'No Signal'. How were they to know that it HAD to be programmed or they should have punched in 44 ?
I punched in 44 and BANG, the TV programmed in the channel as 11-1 thru 11.3. (I wasn't going to sit around for an extra 20 minutes watching the programming progress bar) BUT I left them with the knowledge that from now on if they want to go directly from channel whatever to ch 11-x, they'd have to punch ONE, ONE, Dash, ONE or Four, Four, for the news. Are they confused yet? You bet!

 

[spongella]

You are not alone, our Sony TV gets confused once in a while too. It gets confused between the real channel and the virtual channel.

 

[kittyhas1000legs]

That happened for a few days with WVIT in CT. I messaged then on facebook about their channels showing as 35 instead of 30 and they fixed it a few hours later.

 

[Titanium]

The digital transport stream contains a table of descriptions, which maps the individual data streams to create each service. Part of this table is a description for the service's assigned virtual channel number. These virtual channel numbers were intended to make the digital transition more seamless to the viewer and continuity for the broadcaster's identity. If technology works, great! If not.... confusion.

Occasionally, the broadcaster engineer programs the table with errors and it may not include all descriptions or contains incorrect descriptions. Some TVs simply don't map the table information correctly.

If two services are assigned the same virtual channel (for example during band openings), TVs often assign the duplicate to another channel number.

 

[RONZ]

The re-map is done by something called PSIR filtering. If your Tuner does not see the filter then the turner defaults to the RF channel number. So in the case of WFLD the filter puts the channel on 32-1. If your tuner does not see the filter then it is on 31

 

[jegrant]

For me this is why I think new TVs and DVRs/etc need to include at least a basic EPG that uses the PSIP information broadcast by your local stations. Because with all the virtual channels many stations are broadcasting these days, it's less likely someone knows they want to watch "Channel 23.3" which is actually RF 32.3 - they're going to ask to watch "The 10 PM News on WISH TV" or "CSI: Cyber".

 

[Mr Tony]

Doesn't that make it even more confusing? Different behavior for different TV's. Not many people have the same brand, year and model, throughout the house. Kitchen bedroom and living room.

I'm sure most people just do channel up/down

 

[Mr Tony]

Havent tried it on my new Toshiba TV yet

Tried my Toshiba TV
If I press 11 then enter it goes to 11-1
pressed 4 then enter, it went to 4-1
but if I press 43 (which isnt on the air.....yet)...I get analog 43 (43-0)

So it looks like with the Toshiba as long as there is a station logged under the PSIP, if you just press the first part of the channel it goes to the -1 of that station

 

[TNGTony]

I have a 13 year-old Toshiba. When you hit just two channel numbers, it goes to the ANALOG channel, whether there's something there or not. If it finds a digital channel there, after displaying snow briefly, it switches to the -1 virtual channel there. If it finds nothing, you get to watch the snow until you change the channel.

It comes in handy for the current cable hook-up I have which has virtual -XX channels on the same numbers as analog cable channels. Too bad that's going away (along with the cable subscription) on April 12.

 

[larrykenney]

It sure would have been a lot easier if the NAB hadn't pushed for the analog channel ID that was finally agreed upon. After a couple of weeks, people who were used to FOX 2 would learn to go to FOX 44, to go to CBS 29 instead of CBS 5, etc. Of all the channels in the San Francisco Bay Area only 2 have identical virtual and RF channel numbers, KGO 7 and KICU 36.

What's really confusing is that KTNC 42 transmits on 14, KAXT 1 transmits on 42, and KDTV 14 transmits on 51. KRON 4 is on 38, KCNS 38 is on 39, and KTVJ 12 transmits on 4. There are a few other examples like that. When a tuner doesn't pick up the PSIP info and finds the channel on the RF channel, things can get really messy.

 

[Mr Tony]

What's really confusing is that KTNC 42 transmits on 14, KAXT 1 transmits on 42, and KDTV 14 transmits on 51. KRON 4 is on 38, KCNS 38 is on 39, and KTVJ 12 transmits on 4. There are a few other examples like that. When a tuner doesn't pick up the PSIP info and finds the channel on the RF channel, things can get really messy.

Luckily here in Minneapolis we have just one example of that
WUCW (CW23) is on RF22 but maps to 23-1
KTCI (2nd PBS) is on RF23 but maps to 2-3

One time KTCI had their PSIP screw up which on most older TV's screwed up the PSIP and made WUCW non existent until they fixed it

 

[spongella]

How about this one: We get two channels 4.1 here, one channel is from NYC (WNBC) and the other is 4.1 with several sub-channels, WACP from Atlantic City. It depends on which way the antenna is rotated as to which will be received. I give my TV credit for figuring that one out, guess they are on two different frequencies.

 

[Mr Tony]

I give my TV credit for figuring that one out, guess they are on two different frequencies.

correct
WNBC is on RF28 but maps to 4-1
WACP is on RF4 and maps to 4-1

There are a couple examples like that in Wyoming too and that is due to translators there. As an example in some areas near Montana border they get KTVQ CBS and KULR NBC out of Billings. They map to 2-1 & 8-1 (both have subs). But the ABC which is from Casper, WY is ALSO on 2-1. SO TV's log it as
2-1 KTVQ CBS
2-1 KTWO ABC
2-2 CW+

someone has a youtube video that shows it (note Sheridan doesnt get KULR but other areas near there do)

 

[Mr Tony]

I've noticed this once when I had a weak signal on one 'set' (Television for the young whipper snappers)

I just had that happen yesterday. The "riddle me this" thread station when I scanned on my other TV showed it as 43.7 but once the signal got better it logged as its PSIP station 43.5

 

[Mr Tony]

Somebody mentioned elsewhere that their TV they can manually type in the RF number and it wont change to PSIP numbers unless they do a scan. Thats really odd

So if they type in 32-1 it stays on WCCO but a rescan will put it at its PSIP spot of 4-1