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Over the air TV channels disinformation...

Externet

Well-Known Member
Hi all.
My TV gets its programming over the air.
There is a local channel 56, I watch it daily; a screenshot :


1610897365290.png



And there is supposed to be no channel 56 in 2021 ; another screenshot :



1610897684538.png


WhatTF is the U.S. FCC doing ? Can anyone explain ? :banghead:
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Did you fail to notice when TV went digital?.

The TV 'channel' has nothing to do with whatever frequency the multiplex it uses might be on (and indeed a number of channels will use that exact same frequency) - the channel number is just an arbitrary number used for the EPG, and has nothing to do with frequency.

Generally the lower numbers are considered more desirable, and worth more money - to the extent that in the UK the lowest numbers are only available to PSB's.
 

Externet

Well-Known Member
Thanks.
I did notice it, and the virtual channel numbering garbage had already started by then.
What do you mean by 'multiplex' ? Many same radiofrequency TV channels can transmit on the same if geographically far apart to not interfere .

This is over the air reception of channel 56-11610916381230.png at my location, supposed to not exist over the air. Am not talking about cable nor internet nor subchannels.

1610916381230.png
 

rjenkinsgb

Well-Known Member
Most Helpful Member
Note that the channel info says it is in 720p resolution. That is a digital TV channel.

The existing channel names did not change in the transition to digital TV (around ten years ago), but they no longer have any relation to RF frequency.

See this page, and especially digital TV channels header section:
 

Externet

Well-Known Member
Thanks.
..."That is a digital TV channel" ----> Is there another kind ?
The "Over the air digital TV" link has obsolete data. It shows channels 14 to 69 in UHF. And is the same site as in post 1 where is stated that
there is no channel above 51 since 06/2020.

Kiss... You are saying that the now real RF channel 19 is now called virtual instead for OTA ? And pointing to this senseless

"Former channel number(s): Analog: 56 (UHF, 1986–2009); Digital: 4 (VHF, 2003–2009); 31 (UHF, 2009–2019) and now "called" D56 but actually real 19 ?
It is a mess to puke... :arghh:

Edited... More confusion :
1610933440767.png

Number 6 is talking about the channels numbered before 2021. Otherwise, makes even less sense. Currently, there is supposed to be NO TV OTA above 698MHz. All has been taken by 5G mobile telephony :

1610934074923.png
 
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KeepItSimpleStupid

Well-Known Member
Most Helpful Member
Kiss... You are saying that the now real RF channel 19 is now called virtual instead for OTA ? And pointing to this senseless
The other way around. There is a physical channel which is the old RF channel. The RF channel can support, 9 virtual channels.
19; It could actually support 56-1, 56-100, 10-3 just about anything simultaneously. Scanning, scans the physical chnnels and determoness thier virtual channels.`

There is an analog and digital TSID (Transmit Stream ID) that's a unique identifier across the US that's assigned by the FCC. This is how the program guides work. 10-1 in california is different than 10-1 in New York. The TSID's will be unique.

Scanning scans by physical channel, determines which digital channel is associated with the physical channel. the scanner should also keep the TSID in case there are two or more virtual channels of the same number.

The remote should, but mine doesn't on my SMART TV. If you put in the physical channel of a non-scanned channel, it should find the virtual chanels. MY $50.00 DTTV converter box will work that way. The converter box will access the virtual channels if you input the physical channel.
 
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KeepItSimpleStupid

Well-Known Member
Most Helpful Member
I have two TV's at home with a channel 1. yea, there was an original channel 1. Color TV eliminated channel 1. Don;t forget FM is around channel 6. You used to be able to tune analog channel TV 6 audio on an FM radio.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Thanks.
I did notice it, and the virtual channel numbering garbage had already started by then.
What do you mean by 'multiplex' ? Many same radiofrequency TV channels can transmit on the same if geographically far apart to not interfere .
Try looking up digital TV - it's transmitted in multiplexes, which is a number of different TV channels mixed together and transmitted as one digital multiplex. It's been years now since DSO, where have you been?.

So assuming one multiplex uses the old 'channel' 42 (the actual frequency of channel 42), then that multiplex includes multiple channels - one 'could' be called Channel 56 (I'm presuming that's just it's original analogue name, and there's no need or reason to change it), the others could be called 'Fox News', 'Boring Soaps', anything you want - it's just a text label, and NOT a channel number.

This is over the air reception of channel 56-1View attachment 129112 at my location, supposed to not exist over the air. Am not talking about cable nor internet nor subchannels.

View attachment 129112
I've already explained the '56' has got nothing at all to do with any frequency that might be in use - it's merely a label to place the channel in the EPG.
 

rjenkinsgb

Well-Known Member
Most Helpful Member
This is over the air reception of channel 56-1
It is over the air reception of a channel with the label 56-1.
That is a "virtual" channel, one item out of a multiplex stream, on some RF channel. There is no direct correlation between the two.

Look again at the link & section I directed you to earlier; a virtual channel can be on ANY RF channel:

dtv.png
 

KeepItSimpleStupid

Well-Known Member
Most Helpful Member
If i set up a modulator at home for ATSC, I can pick what I want displayed and I can pick the RF channel. I would ghave an HDMI input for every stream and I probably should assign it a unique TSID (Transport Stream ID) that's unique for my location.

e.g. A TSID of 1000 might always mean program #3 in California TY station with call letters <WWWW> everywhere in the US.

Just like MAC addresses for the Internet, they are generally unique to make life easy, but in reality only have to be unique over routeable segments. This, you can clone MAC addresses.

You have a MAC address, an Ethernet address and a port # that differentiate a stream of Ethernet traffic.
 

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