--- Barry C' <[EMAIL PROTECTED]> wrote: > > > > >From: "Laryn Lohman" <[EMAIL PROTECTED]> > >Reply-To: [email protected] > >To: [email protected] > >Subject: [Repeater-Builder] Re: Antennas that work > both in commercial and > >amateur > >Date: Fri, 16 Feb 2007 05:04:02 -0000 > > > >--- In [email protected], "Barry C'" > <[EMAIL PROTECTED]> wrote: > > > > > > > > > Well lets look at the riddle , swinging a > radiator acree 20 or 30 > >megs of > > > bandwidth it will tune and still radiate but > will it have > >appreciable gain > > > away from certain design points? > > > I think not . > > > >OK, within certain unspecified parameters, I would > agree. Let's be > >more specific. I referred to the ASPB602 in an > earlier post, which > >has 6 or 9 dbd gain, depending on dipole > configuration around the mast > >(normal for four stacked dipoles), and bandwidth of > 144-162 mc (wider > >than most antennas in this range). Just trying to > understand Barry, > >do you agree that these specs are valid? Depending > on your answer, we > >can discuss further... > > > I presume its some sort of stacked arrangment , in > chich case it will make > that gain at resonance , > > claims are like water (sic) > >Laryn K8TVZ
We have a couple of the Telewave broadband antennas, and they do seem to exhibit the gain over the advertised bandwidth. They are rated at 138-174, and do have good SWR over that range, and good gain. They replaced DB224 antennas at the same locations on the tower, and give exactly the same coverage. We have radios at 145, 153, and 168MHz on one antenna, and all radios perform the same, no difference in gain was noted. There may be some skewing of the vertical radiation angle at the different frequencies, but we haven't noticed that either. Telewave only makes one model of antenna to cover the whole VHF range. The same antenna is sold to those who use it at 170 as those who use it at 140, and no gain changes are noted in the literature. I'm sure there are differences in the gain, but they are miniscule, certainly nothing major. There are lots of antennas that have gain and wide bandwidth, the two are not mutually exclusive. A Stationmaster and SuperStationmaster look similar, and have similar gain, but the SSM will have 8MHz of bandwidth on VHF compared to less than 2 for the SM. Joe ____________________________________________________________________________________ Need a quick answer? Get one in minutes from people who know. Ask your question on www.Answers.yahoo.com
