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Which ever version of the C3 you get, get two of them the same. Given what you have related, I would certainly recommend the C3SS, for cost, for use of a small rotator, and for the short boom which will not resonate on ten or fifteen meters and wierd out 10/15 performance on the trap dipole. This also means make the lower one a C3SS as well. (If you get on the F12 site you will see very little difference between C3S and C3SS, except C3S has a few tenths of db more gain on 20, and the C3SS has better F/B on 20.) It sounds like your critical directions are east, south and CA. What that means to me is use a rotator with a brake up top. Then what you do is when you are done, always park the top C3SS at east. Fix mount the lower C3SS at 285 or whatever CA is from your location. With the top C3SS at east the dipole will be broadside north-south. The lower C3SS should go above the bottom guys (I assume with Rohn 45, you are guyed at 70' and 35'), at a distance thirty feet to 35 feet below the top one. Ten feet is *WAY TOO CLOSE*! BTW, according to contesters, roughly 45-50 feet is a "sweet" height for easc coast to west coast propagation. Plan ultimately to be able use them as a stack in an important direction that needs some power. The lower C3SS can be put on a "swinging gate" rotator setup. Separate the dipole from the upper C3 boom by *FOUR* feet, not two. The usefulness of a stack will become apparent sometime when the band is stinky and you want to communicate through marginal conditions. The performance of a C3 stack at 30-35 spacing is becoming legendary, easily exceeding much larger single antennas, elimating pattern nulls at important arrival angles, which in turn eliminates null-induced fading, and improving the pattern at low angles. The C3SS's operating as a stack will be the most reliable system, since the number of "propagation near failures" will exceed mechanical failures by a wide ratio. On Mon, 10 Jul 2000 16:11:08 -0400, you wrote: >Dear Pete & Guy: > > Sure appreciate your efforts to get me pointed in the right >direction! And my antennas too! ;-) > > I currently own a T2X, a HD-73, and a lightweight tv rotator. >I am trying to avoid using them in a "mission-critical" application. >The T2X is what I plan to sell or swap towards C3SS number >one. A Ham owes me money and I will ask him to pay up by >purchasing my second C3SS. > > The Rohn 45 is here ready to go up as is the Phillystran -- so >no guy-wire interaction issues. > > My goal is to have the main antennas fixed in the directions I >will most likely to need for emergency and missionary communications. >Arrival angles are also a consideration, together with direction. > > The top beam would assure solid communications to Africa and >still be somewhat useful towards Europe, Eastern Europe and Asia. > > A second beam a little lower would still be effective into TX, >the West Coast, and beyond. > > I was worried that the D4 would be too much up near the top but >really wanted it close to 70 feet for improved 40m effectiveness! I will >use the Mosley to help pay for the first C3SS and rely on the D4 to >cover the Caribbean, Central and So. America, and the central US, as >well as down-under to the Aussies and New Zealanders. My NVIS >and low-dipole will have to handle East-West on 40m. > > So, a C3SS or C3S at 78 feet, the D4 at 76 feet and the second >C3SS or C3S at 70 feet is acceptable? Or do I need to get the lower >C3SS (or whatever) even further down? > > This provides for DX arrival angles and the D4 will probably be >broad enough to capture some lower stuff as well. I can always get >a third C3SS/C3S and put it at 40 feet on an arm and point it South. >I could use the HD-73 to turn it ... should that be necessary. > > I can also use the long low dipole for stuff the beams don't hear >due to angles and direction. And I have room for a vertical should >such be dictated. > > The Comet seems to be irrelevant except as it increases the stress on >the mast -- I can reinforce the mast with a solid 12 foot inner sleeve with >6 feet above and below the tower top if that will make a significant >difference. > > This all sounds like a plan! The separation of the top two beams >seems the only sticking point. > >- Thanks! & 73, DavidC K1YP in Hudson, FL >************************************************************************ > > > >Why pay for something you could get for free? >NetZero provides FREE Internet Access and Email >http://www.netzero.net/download/index.html 73, Guy k2av@contesting.com Apex, NC, USA -------------------------------------------- Force12Talk mailing list provided as a service by Force 12 Antennas, Inc. Force 12 Web site: http://www.qth.com/force12 Submissions: send to Force12Talk@qth.com To unsubscribe: send a blank e-mail to Force12Talk-leave@qth.com Force12Talk Message Archive: http://www.qth.com/force12/list/force12talk For problems with the list, contact force12@qth.com |
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