<div dir="ltr"><br><br><div class="gmail_quote">On Tue, Sep 9, 2008 at 6:29 AM, Brian Wood <span dir="ltr"><<a href="mailto:beww@beww.org">beww@beww.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="Ih2E3d">Allen Edwards wrote:<br>
<br>
> At some point, the government realizes that they could cram all the<br>
> stations into less spectrum with the new format and sell off the parts<br>
> that were better used by other services. I think that came later.<br>
<br>
</div>It's not really "cramming" them into less spectrum, it was the idea of<br>
moving everyone to UHF, where there is more space (there are more big<br>
numbers than smaller ones). The actual bandwidth used stayed the same,<br>
though you could argue it is being used more efficiently.<br><br>
beww</blockquote><div><br></div><div>Well, they can get more stations in the same total BW but you have to be thinking big picture. Each station has the same BW but the band plan is tighter. With analog TV, if you put a station on a channel, you can't use some rather large number of other channels. One source I saw said that assigning channel 30 blocked 19 other channels. That seems excessive but they are putting DTV stations right next to each other. </div>
<div><br></div><div>Whatever the details, what is certain is that you can get more DTV stations in the same number of available channel slots because you don't have to leave so many empty.</div><div><br></div><div>When you expand this problem to different geographies, the DTV advantage is even greater. They can "cram" more stations across the geography than they could with analog TV because these digital stations just don't interfere with each other nearly as much. If they require directional antennas, the geographical reuse is even better. I am not sure if that is a requirement or not.</div>
<div><br></div><div>That is what I was talking about in terms of cramming. They can cram more 6MHz channels in the overall BW allocated to TV. Analog TV was very inefficient because of the adjacent channel and other requirements. DTV doesn't have that problem.</div>
<div><br></div><div>Allen</div><div><br></div></div></div>