04-12-15 07:57 TOM WALKER wrote to ED VANCE about Digital TV Channel Freq.

 TW> {at}MSGID: 
 EV>According to the website TVFOOL.COM the Over The Air Digital TV Channel
 EV>21.1 is a Virtual frequency, and is Transmitted on the Real Channel 8 .

 EV>I was thinking Channel 21 was UHF until I read that the other day.

 EV>Channel 8 is VHF as far as my thinking processes goes from what I read
 EV>about TV Channels in books that I have here.

 EV>Channel 8 is between 180-186 Megacycles,
 EV>Channel 21 is (was?) between 512-518 Megacycles,
 EV>according to a book printed in 1959.

 EV>That seem to me to mean I would need a VHF TV Antenna instead of UHF.

 EV>Is that how You think also?

 TW> The Main Station frequency sub channels are Multiplexed on the
 TW> main carrier. They do also typically use the main channel
 TW> number followed by .1, .2 etc. In the case you are talking
 TW> about I suspect they could be Retransmitting the UHF Channel 21
 TW> along with their main channel.

 TW> The standard digital TV channel bandwidth is capable of
 TW> containing more then one video channel. the number being based
 TW> on the Resolution of the channels. As an example if the main
 TW> carrier is a 16:9 720P signal there can be Five 4:3 480i
 TW> channels also transmitted.

Thanks Tom,

In olden times a TV Channel occupied 6 Megacycle of space,
iirc Video used 4.3 Megacycles of the space and Audio used the rest.

I will have to read up on that 720p and 480i stuff some to understand
it.  Watch out Wikipedia, here I come. I read up on lots of things even
though I know some of what is written is personal opinion and not fact.

Is the main frequency that Digital TV Channel 21 point whatever,
transmits on Channel 21 or Channel 8. what I saw on TVFOOL.com messed
up my mind, which is already messed up a bunch just by my playing with
computers

I think I've seen point 6 on one of the Stations we can get,
If I'm reading wht You wrote right they are transmitting the point 1
channel at 720p and five other 480i channels.

-*-*-*-*-*-*-*

After reading part of the Wikipedia articles on ATSC, HDTV, etc., I
will have to read them completely to try to learn about this new stuff.

I think it may be over my head but I'll take some more time studying
about what's with Over The Air Digital TV.

Thanks Again for the reply.
73

... Being young is beautiful, but being old is comfortable. -- Will Rogers
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