Mike, you suggested a delta loop. It is important that if Simon decides to hang a delta loop between towers that you feed it a the corner rather than at the bottom. This should give you some vertical component at a much lower take-off angle rather than being a clod warmer on 80 meters. Unfortunately, the towers supporting the delta loop will modify the pattern a bit but if the broadside is in a favored direction it could actually help you. Maybe someone could model this for you even though if would be a complex assignment. Herb Schoenbohm, KV4FZ
On Sat, Sep 15, 2018 at 1:11 AM Mike Furrey <[email protected]> wrote: > Hi Simon,I would like to suggest hanging a 1 wavelength delta loop off of > the 50 meter tower. Easy to build, easy to match, about 1.5 db gain and you > don't need to do all that work laying down radials, etc and trying to match > an odd length tower. The loop will be almost omni directional and it will > be bit more broad banded than a vertical, dipole, etc. > > GL es 73, Mike WA5POK > > > On Friday, September 14, 2018 1:34 PM, Simon Ravnič via Topband < > [email protected]> wrote: > > > Hi! > > > > With a head full of browsing and researching I decided to ask for help > this Topband think tank. > > > > At S53M contest station we are well organized for 40m & up but are lacking > lower band TX antennas. > > > > There are three towers in direction north - south: > The southern one is 50m high with 40m and 20m monobanders on top > Middle one is located 25m north of previous one and is 25m high with 15m > monobander and 6/4m duobander. > The northern one is 28m north of middle one and is 20m high with Optibeam > OB17-4. > > > There is a possibility to hang anything between them so I think we would > prefer some wire antennas. Already present on the site is 160m INV-V and > 80m vertical dipole from the 50m tower. What we are looking for is 160m and > 80m TX antenna with two main directions 310 and 45 with low angle radiation. > > > > RX antennas are OK as there are three 280m long terminated beverages, > direction 270 (Caribbean), 310 (NA) and 45 (AS). > > > > To understand better see a photo of the location at > > https://www.dropbox.com/s/bk44cg2zfyzpw3w/S53M.JPG?dl=0 > > or > > https://ibb.co/gRPGVU > > > > Thanks you for your idea & 73 > > Simon, S53ZO > > S53M team > > > > > > > > > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > > > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > _________________ Topband Reflector Archives - http://www.contesting.com/_topband
