George, Are you familiar with the Franklyn antenna design? Some broadcasters swear by them and claim a 3 db increase over a 1/4 vertical radiator.
Herb, KV4FZ On 9/22/2011 9:08 PM, GeorgeWallner wrote: > On Tue, 20 Sep 2011 17:17:58 -0400 > Guy Olinger K2AV<[email protected]> wrote: >> I share the frustration over the very minimal amount of >> data out there. >> >> However... >> Erection of a 260 foot vertical in a testing >> environment... > G'Day Topbanders, > > I am not sure how general a conclusions could be drawn > from my experience, but I have a set up that is somewhat > relevant to this thread, and have done some on the air > testing with it. > > I have two verticals, about 2 meters apart. One is 21 > meters tall and the other one is 28 meters tall with a > high Q center loading inductor to make it resonate at 1900 > kHz (this is my 160 m antenna). This antenna is fed via a > low loss antenna coupler. The two antennas share a common > ground system, which is salt-water to the east and a > buried field of 40 radials of varying length between 30 > and 120 feet long to the west. On 80 meters the shorter > antenna is a 1/4 wave vertical, while the longer one could > be considered to be a half-wave vertical. > > I have done extensive tests on 80 meters, comparing the > two antennas towards the east. I have used the reverse > beacon network, and a couple of friends' SDR-s in Europe > for these comparisons. In tests from my Florida QTH, > towards the east (towards Europe) and the side where the > salt water is, the taller antenna has almost always been > better by 2 to 3 dB. Towards the west (and the land side) > I have not done enough testing to draw conclusive results, > but I feel that the 1/2 wave vertical is better in that > direction too. > > I understand the 80 meters is not 160 meters, but... > > I would be happy to set up a test sched with anyone to my > west or north-west, who is interested in carrying these > studies further. > > 73, > > George, AA7JV > > PS: BTW, I almost always use the 1/4 vertical on 80 > meters, even towards the east, as going through the > coupler is a PITA (as Guy has pointed out). > _______________________________________________ > UR RST IS ... ... ..9 QSB QSB - hw? BK _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
