Adding VHF OTA with 2 digit sub-channel

[WMCLives]

One of my OTA channels, CH3, in zip 11550 has 2 digit sub-channels. Since WMC doesn't scan VHF OTA I have to manually add. WMC doesn't allow me to enter a 2 digit sub-channel. The EPG123 Client Guide Tool shows the channels in lineups on the right pane but not in the left pane.

[garyan2]

You can add it manually with the epg123 client tool. It will allow up to 3-digit sub-channel numbers.
https://garyan2.github.io/addchannels.html

[WMCLives]

Hi,

Gosh, tried it, so easy! Thanks.

[Space]

Gary, can you clarify exactly what this is doing?

This ATSC mapping has always been confusing to me.

In the video example on that page, when you give physical channel "9" (is this also known as RF channel?), and then add channels 9-1, 9-2, 9-3, 9-4, and 9-5. What does that do exactly?

If I had to guess, when WMC receives the signal for physical channel 9, it gets a list of all the logical channels on that physical frequency. The list of all those channels may be something like this:

9-1
9-2
9-3
9-4
9-5
9-22
22-11

You then map a WMC channel to these channels by saying you want 9-1, 9-2, 9-3, 9-4 and 9-5 to show up in your guide, ignoring 9-22 and 22-11.

What would happen if you told WMC to add channel 9-6 from physical channel 9? Would it just not work? Would it give an error (logical channel 9-6 is not one of the valid channels being advertised on physical channel 9)?

Also, if you look at WMCLives lineup, you see that physical channel 3 lists a bunch of physical channels, 3.3, 3.4, 3.6, etc. and they are mapped to display (logical?) channels 33.1, 33.2, 33.3, respectively.

What exactly are the numbers used as the "subchannel" of the physical channel (3.3, 3.4, 3.6)? It appears that these numbers are not used by WMC for anything and should just be ignored.

[garyan2]

In the video example on that page, when you give physical channel "9" (is this also known as RF channel?), and then add channels 9-1, 9-2, 9-3, 9-4, and 9-5. What does that do exactly?

Yes, physical channel is the same as the RF channel. When adding the channels, the physical channel is the RF channel the tuner will tune to, and the channel number is the virtual (logical) channel number of the stream within the transmission. When WMC tunes to the channel, it will tune to RF channel 9 and locate the stream with matching virtual channel numbers.

If I had to guess, when WMC receives the signal for physical channel 9, it gets a list of all the logical channels on that physical frequency. The list of all those channels may be something like this:

9-1
9-2
9-3
9-4
9-5
9-22
22-11

You then map a WMC channel to these channels by saying you want 9-1, 9-2, 9-3, 9-4 and 9-5 to show up in your guide, ignoring 9-22 and 22-11.

No need to ignore 9-22 or 22-11. They are still on the physical RF channel. They are just the virtual channel numbers.

What would happen if you told WMC to add channel 9-6 from physical channel 9? Would it just not work? Would it give an error (logical channel 9-6 is not one of the valid channels being advertised on physical channel 9)?

Since 9-6 is not a valid virtual channel number, it will not work. WMC will say there is no signal.

Also, if you look at WMCLives lineup, you see that physical channel 3 lists a bunch of physical channels, 3.3, 3.4, 3.6, etc. and they are mapped to display (logical?) channels 33.1, 33.2, 33.3, respectively.

What exactly are the numbers used as the "subchannel" of the physical channel (3.3, 3.4, 3.6)? It appears that these numbers are not used by WMC for anything and should just be ignored.

Correct. Any physical subchannels should be ignored since WMC only cares about the RF frequency and virtual channel numbers. That is all that is needed for WMC to pull the correct stream.

[Space]

I guess I did understand it for the most part then.

When I said ignore those two virtual channels, I just meant that you were not interested in them, so you chose not to map them to channels in the WMC guide.

One other question, I noticed in the example video you did not put anything in the "Call Sign" field for each virtual channel, why is this? Also, what information (if any) will be learned from the data sent from the digital channel itself (such as call sign, etc.) and will that data be populated anywhere in the WMC database?

[garyan2]

That's where my confusion comes in... there is no 9-22 or 22-11 in my market so I wasn't ignoring anything.

If you manually add a channel in WMC, the page requires something in the call sign (name) field. I found that it was not necessary to actually have anything there so for epg123 it is completely optional. I don't believe it will "learn" anything from the manually added channels, but that may be due to driver settings for my tuner on my end (background scanning).

[Space]

That's where my confusion comes in... there is no 9-22 or 22-11 in my market so I wasn't ignoring anything.

I was just making those channels up as an example. Ideally, if you enter the physical channel number, WMC should be able to just automatically add all the virtual channels on that physical channel. In fact, this is the way I would think it should work rather than have to manually enter channel numbers that WMC already should know about from the broadcast on the physical channel.

My point of "ignoring" those two channels was just to indicate that even though they may be there, WMC does not auto-add them, they need to be manually added, and not only that, you have to use a third-party source to even learn what virtual channels may be available to you on that physical channel (which to me seems kind of stupid since theoretically WMC already knows what channels are there and could either auto-add all of them or at least display them to you so you can specify which ones you want added).

I understand that WMC does already do an auto-scan for UHF channels, but I am not sure if you manually add a UHF channel if it does what I indicated it should do (automatically add all the virtual channels on that physical channel).