What's nastier is T-band sharing. WCVB in Boston on channel 20 routinely hammers a number of 500 MHZ public safety systems in New Jersey.
________________________________ From: Milt <men...@pa.net> To: Repeater-Builder@yahoogroups.com Sent: Tue, August 3, 2010 6:56:05 AM Subject: Re: [Repeater-Builder] Narrowbanding That may be what the mask specifies. I have seen the curve plots of the mask. Now run the numbers and see what kind of signal levels that really equates to when the DTV station is running say 1 MW. It looks pretty on paper, it's not so pretty in the real world. ----- Original Message ----- From: "Glenn Little WB4UIV" <glennmaill...@bellsouth.net> To: <Repeater-Builder@yahoogroups.com> Sent: Monday, August 02, 2010 11:23 PM Subject: Re: [Repeater-Builder] Narrowbanding >I do not know about Nextel, but, the US DTV signal fits into a 6 MHz >bandwidth. > We use a mask filter to ensure that the bandwidth is no more than 6 MHz. > 500 kHz from band edge <= -47 dB > 6 MHz from band edge <= -110 dB > > 73 > Glenn > WB4UIV > > At 10:58 AM 8/2/2010, you wrote: >>On 8/2/2010 10:45 AM, Scott Zimmerman wrote: >> > I was wondering about that myself. The bandwidths spec'd just didn't >> > seem to compute in my feeble mind. >> > >> > Scott >> > >> > Scott Zimmerman >> > Amateur Radio Call N3XCC >> > 474 Barnett Road >> > Boswell, PA 15531 >> > >> > >> > Jeff DePolo wrote: >> >> >> >>> Florida Repeater Coordinator proposes narrowbanding: >> >>> >> >>> http://www.florida-repeaters.org/FRC%202meter%20narrowband%20p >> >> olicy%20released%207-18-10.pdf >> >> >> >> Apparently Carson's Rule works different in Florida than it does >> everywhere >> >> else. >> >> >> >> --- Jeff WN3A >> >> >> >>Course, wiki says Carson's rule "is of little use in spectrum planning" >>anyway...(http://en.wikipedia.org/wiki/Carson_bandwidth_rule). These >>must be the same people that think Nextel's iDen 6:1 TDMA format fits in >>a 25 KHz channel, or that think the US DTV standard fits in a 6 MHz >>channel...NOT! >> >> >> >>------------------------------------ >> >> >> >>Yahoo! Groups Links >> >> >> > > > ------------------------------------ > > > > Yahoo! Groups Links > > > ------------------------------------ Yahoo! Groups Links http://docs.yahoo.com/info/terms/
