This has always interested me, and I've never seen a good technical reason for a loss of range with narrow deviation and receivers, either. But <somewhere> one must exist. If it didn't, there'd be no reason not to take analog deviation down to say, 1 kc., or 0.1 kc., would there?
And I don't think that knowing a repeater's tail signal strength doesn't change is an apples to apples comparison. Laryn K8TVZ --- In Repeater-Builder@yahoogroups.com, MCH <m...@...> wrote: > > This makes no sense. On the same band, with the same power, and with the > same modulation type (analog) there is no reason there should be any > loss by lowering the deviation and narrowing the receiver. > > If there was a change, it is not due to making the bandwidth more > narrow. Maybe the new equipment is not as 'robust' as the old equipment. > (IOW, both were putting out 50W, but the new one has more energy > off-frequency). Or, maybe your new equipment's receivers are not as > sensitive as the old ones. > > A good test of apples-to-apples is to see if a repeater's tail is lower > in signal strength than the modulated/repeated carrier, as you're > comparing the same thing - a signal of lower deviation to one of higher > deviation. You should notice no difference whatsoever. > > Joe M. > > Andrew Seybold wrote: > > > > > > Bill one of the losses if a County fire department system which has 6 > > simulcast repeaters( 150 MHz) operating on wide-band with about 85% > > coverage of the County, and we put in three new channels (after almost 2 > > years of coordination and finding the correct channels), we put them up > > using the same sights and same output (50 watts erp) and using the same > > antennasâ"the new 3 channels under talk the existing wide-band systems by > > at least 30 percent. We are in the process of adding 2 new sites to make > > up the difference. > > > > > > > > I am glad that you did not have a problem but this is just one of > > several which I have had a problem with, and I have become a believer in > > lost coverage, I have yet to see a system that has not lost coverage, I > > am glad that you have. > > > > > > > > Andy > > > > > > > > > > > > *From:* Repeater-Builder@yahoogroups.com > > [mailto:repeater-buil...@yahoogroups.com] *On Behalf Of *Bill Smith > > *Sent:* Friday, August 27, 2010 5:58 PM > > *To:* Repeater-Builder@yahoogroups.com > > *Subject:* Re: [Repeater-Builder] Re: Seeking emergency system design help > > > > > > > > > > > > Andy, my comment was not directed at the professionals, such as yourself > > and others I know personally that are on this list. They were based > > on his stated requirement for a disaster recovery radio system. It's not > > something to do cheap or without expert guidance. > > > > > > > > People keep commenting on losing range with narrowband systems. A large > > UHF LTR system I installed and maintained lost no discernable range > > switching from 5 KHZ to 2.5 KHz. All else was the same. Same antenna > > system, same repeaters, same mobiles. They just pushed a button to bring > > them to the new talkgroups. > > > > > > > > Bill > > > > KB1MGH > > > > ------------------------------------------------------------------------ > > > > *From:* Andrew Seybold <aseyb...@...> > > *To:* Repeater-Builder@yahoogroups.com > > *Sent:* Fri, August 27, 2010 5:39:21 PM > > *Subject:* RE: [Repeater-Builder] Re: Seeking emergency system design help > > > > > > The FCC is re-thinking the move to 6.25 KHz based on the fact that > > narrow band systems (and I have done a few of them) lose about 30% of > > the existing coverage AND the NEW FCC believes that broadband is what it > > is all about in the futureâ"no matter that broadband cannot do simplex or > > any of the other stuff needed for LMR and public safety. > > > > > > > > And like a few others have said on hereâ"you have to narrowband but are > > NOT required to move to digitalâ"P25 or anything else, I have just > > completed several systems which use analog and we have moved them from > > Wide to Narrow with no problemsâ"EXCEPT the coverage problems I mentioned. > > > > > > > > Andy > > > > W6AMS > > > > (and btw there are professional LMR folks and consultants who work with > > this stuff every day on this list, just because we are hams too does not > > mean that we are not in the business as well) > > > > > > > > >
