Broadcast new

WB4JFI wb4jfi at knology.net
Tue Aug 12 01:18:13 CDT 2008


Yes, WETA (RF channel 26 analog) was assigned RF channel 27 for DTV.
Through the magic of PSIP, you can BRAND your signal to be completely
different than where the RF actually is.  When a tuner is new (or when the
local stations mess up), you must manually scan the entire TV RF spectrum.
The tuner will look for 8-VSB/ATSC signals, and each time it finds one, it
looks inside the PSIP for how that channel should be branded.  For example,
W*USA transmits DTV right now on RF channel 34, but it is branded as channel
9.  The first media stream is 9-1 (or 9.1), the second is 9-2, etc.

PSIP is very complicated (as is the whole MPEG2 data stream), and sometimes
station's have gotten it wrong.

Even the analog channel is now "branded", although through a different
mechanism (vertical interval data).

Some stations will be staying on their DTV RF channel assignments after the
transition next February, such as WRC (NBC4), which will stay on RF channel
48, but will still call themselves NBC4.  Others, like W*USA and WJLA, will
go back to their old analog RF channels with teh digital signal.  Most
stations were able to pick their poison, er.. RF channel, and most selected
high-VHF if that's the original analog channel (WJLA=7, W*USA=9).  Others,
like WRC (4) and WTTG (5), were on low-VHF channels, and decided those
channels were problematic.  So, they opted for their UHF DTV channels.

Most stations that were already on UHF for analog kept their digital UHF
channel assignments, as the cost to move back to their analog channel would
not be offset by any real benefit.  I'm not sure what WETA selected, to go
back to 26, or stay with 27.  In the back of my mind I sort of remember they
chose to go either on the joint (WJLA/W*USA) tower on 27, or maybe WTTG's
tower on 27.  It's been two years that I've been out of the market....

Next February should be VERY interesting.....
Terry


> -----Original Message-----
> From: Robert Stratton [mailto:bob at stratton.net]
> Sent: Monday, August 11, 2008 11:39 PM
> To: WB4JFI; Michael O'Dell; W4KRL at arrl.net
> Cc: tacos at amrad.org
> Subject: RE: Broadcast new
>
>
> I admit I haven't looked at the tables bu were WETA's DT channels
> actually
> being transmitted on ch. 27-x for a while? I could have sworn I plugged
> either 26 or 27 into my box and  found channels on the one I
> didn't enter.
> This was an older Zenith HD STB.
>
> -- Bob S.
>
> ...... Original Message .......
> On Mon, 11 Aug 2008 21:52:24 -0400 "WB4JFI" <wb4jfi at knology.net> wrote:
> >Yes, the same freqs as analog.  30.1-30.5 are sub channels of the main
> >digital stream.  The DTV tuner box will separate the streams to their
> >individual channels.
> >
> >Terry
> >
> >
> >> -----Original Message-----
> >> From: tacos-bounces+wb4jfi=amrad.org at amrad.org
> >> [mailto:tacos-bounces+wb4jfi=amrad.org at amrad.org]On Behalf Of Michael
> >> O'Dell
> >> Sent: Monday, August 11, 2008 9:11 PM
> >> To: W4KRL at arrl.net
> >> Cc: tacos at amrad.org
> >> Subject: Re: Broadcast new
> >>
> >>
> >> Karl W4KRL wrote:
> >> > over-the-air digital channels
> >> > DT-30.1 - DT-30.5 will still be in operation.
> >>
> >> so where are the digital channels?
> >> is "DT-30" the same as "Analog 30"?
> >> ie, 567.25-571.75 MHz
> >>
> >> 	-mo
> >> _______________________________________________
> >> Tacos mailing list
> >> Tacos at amrad.org
> >> http://www.amrad.org/mailman/listinfo/tacos
> >>
> >
> >_______________________________________________
> >Tacos mailing list
> >Tacos at amrad.org
> >http://www.amrad.org/mailman/listinfo/tacos
>
>



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