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## [Towertalk] Radial "fan out"/forking - MMANA model wanted

 To: [Towertalk] Radial "fan out"/forking - MMANA model wanted n8de@thepoint.net (Don Havlicek) Thu, 28 Feb 2002 15:00:14 -0500
 ```I've been following this thread since it began. Sorry, but I don't understand WHY anyone would want to go through all the trouble of doing this. My reasoning is this: IF you intend to 'fan' the radials .. that would cause the 'fan' elements to be CURVED or BENT to keep them from crossing OTHER 'fan' radial ends. Draw a diagram of it on a piece of paper. If you intend to put, let's say, 12 radials from the base of the vertical, each sector between radials would be 30-degrees. That limits ANY 'fan' to 15-degrees. In fact, to keep the radials spaced 'evenly', that means they would be required to fit in a 10-degree sector. Remember, the space between two radials connected to the vertical base must be SHARED by 'fan' wires from neighboring radials... I don't like the prospect of the messy arrangement. Go ahead and 'model' it .. but I think you're wasting valuable time, energy, money, and copper! Now you say you're going to elevate the vertical, with the radials sloping from 15' to ground .. At 30-degrees, that means the radials will meet the ground approximately 26' from the base of the vertical. Doesn't seem to give you much room for 'bending under them'. I totally agree with those who have said "put the radials on/in the ground". That's what has been most successful for me. I have a 3-element 40m vertical array with 36 1/4-wavelength radials, spaced 10-degrees, beneath the 'main' vertical .. and an insulated, 60' tower [no antennas on it] that is my 80m vertical, that has 60 1/4-wavelength radials, spaced 6-degrees, with an additional 10 radials at smaller spacings .. placed to the NE for Europe, SE for the Caribbean, NNW for Japan, and W for VK/ZL. Don N8DE Pat Rundall wrote: > > For me at least, this remains in my mind as > an "unsolved antenna mystery". A few have > asked "why bother messing around with the > forked radials idea - just put down 60 1/4 wl > radials and get it over with?" > > In my case, I'm considering forked radials (at > least, a minimal amount of wire and "stuff to > duck under when mowing the lawn) for a Butternut > vertical on a mast mount (at ~10' to 20' height) > with the radials sloping to ground. 60 .25wl > radials sloping to ground at ~30 degrees from a > height of 15' turns a simple secondary antenna > into a rather complex one. Assuming that > because it is mast mounted and off the ground > (the radials are somewhat elevated to begin > with), perhaps a greatly reduced number of radials > eminating from the mast would suffice. > > I'd like to eventually model this, but the only > modeling package that I have at the moment is > the FREE one - MMANA (a fun free modeler - check > out http://www.qsl.net/mmhamsoft/mmana/) which > probably isn't ideal for this sort of thing. > > Once I get around to it, I'd like to model > "standard forking"... > where A=B=C=D=(~.125 wl) and A slopes to ground > from 10' at the mast (M) at ~40 degrees. > > / > B / > / > A / C > M----------------- > \ > \ > D \ > \ > > "multiband forking"... > where A=.125 wl on say 40m and ~.06 wl on 80m, > B=.19wl on 80m (to finish the 1/4 wl), C=.125wl > on 40m, etc. > > "upclose forking"... > where A is very close to the mast (a 45 degree > slope) and forks as soon as A hits the ground. > > and finally "reverse forking"... > I doubt this makes any sense at all. > > ^ > A/ \ > / \ > C / D \ > -----<------->M > \ / > \ / > \ /B > V > > In fact, I have my doubts about quite a bit of > this (especially the multiband forking - which > electrically needs a lot of work), but it should > give me something to do while waiting for the > ground to thaw to actually try this stuff. > > Pat, N0HR > > ================================================= > MobileLog - ham radio logging for the PocketPC > Windows CE devices: http://n0hr.tripod.com/ > ================================================= > > __________________________________________________ > Do You Yahoo!? > Yahoo! Greetings - Send FREE e-cards for every occasion! > http://greetings.yahoo.com > _______________________________________________ > Towertalk mailing list > Towertalk@contesting.com > http://lists.contesting.com/mailman/listinfo/towertalk ```
 Current Thread [Towertalk] Radial "fan out"/forking - MMANA model wanted, Pat Rundall [Towertalk] Radial "fan out"/forking - MMANA model wanted, Don Havlicek <= [Towertalk] Radial "fan out"/forking - MMANA model wanted, Joe Subich, K4IK [Towertalk] Radial "fan out"/forking - MMANA model wanted, Chris BONDE [Towertalk] Radial "fan out"/forking - MMANA model wanted, Joe Subich, K4IK