Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!ux1.cso.uiuc.edu!ux1.cso.uiuc.edu!uxe.cso.uiuc.edu!mcdonald
From: mcdonald@uxe.cso.uiuc.edu
Newsgroups: comp.sys.ibm.pc
Subject: Re: BULLEish on Zenith Data Systems
Message-ID: <110200016@uxe.cso.uiuc.edu>
Date: 18 Oct 89 00:40:33 GMT
References: <3938@blake.acs.washington.edu>
Lines: 17
Nf-ID: #R:blake.acs.washington.edu:3938:uxe.cso.uiuc.edu:110200016:000:877
Nf-From: uxe.cso.uiuc.edu!mcdonald    Oct 17 09:27:00 1989


I fail to see where the problem with bandwidth for HDTV lies, other
than with the FCC. There are 81 channels available, 6 MHz each.
Around here the following ones are used: 3, 12, 15, 17, 22, 27, 55.
Hmmmm --- that leaves 74 channels free. Say we use only UHF channels
for HDTV, and take 18 Mhz for a channel. 15 could expand to 14-15-16,
17 to 17-18-19, 22 to 20-21-22, 27 to 26-27-28, etc. That is 23 
channels with 18 mhz each. A good HDTV transmission scheme would
use FM instead of AM so that the capture effect would allow stations 
to be closer together (both in frequency and space.)

Besides - have you ever looked at the spectrum of the air with a
spectrum analyzer? I have - and, except for broadcast bands, CB, ham
bands, and things like taxi bands - there is GOBS of free space.
Vast areas of the upper reaches of the spectrum are completely empty.

Doug McDonald