OK RR, sounds good... Your broadside is directed to me, so you RF lobes would be radiated in my direction (Im guessing you follow what Im saying so far, but this is as much for the readers too...). Since the dipole has greater emissions to the side, then we must assume sensitivity to reception would be similar... greater sensitivity from the side as well. Reception is not as "critical" as transmission, but understanding a horizontal antenna gives better insight.
On my end, I am running a vertical... so my RF has a different polarity. That doesnt always make any difference, guys with dipoles have been talking to guys with verticals for as long as ham radio has been around! However, if the distance or conditions are not "ideal", then the offending polarity *may* play a role in our inability to communicate.
Lastly, there is the take off angle, or the angle of which the RF "takes off" of the antenna... I could write a book on the subject and still not cover it, so I wont attempt to do it here... be it said though, the take off angle of an antenna will determine (in part) the effective range of your transmission.
On reception, the antenna doesnt really need to do much more than be in the zone where the RF is coming in. It doesnt necessarily need to be oriented any particular way or be any specific length (assuming were not talking about any type of YAGI design), but the rule of thumb will always be the same, the more wire in the air, the more RF it can receive. Think of it as a tarp collecting rain water.
Anywho, we SHOULD be able to communicate, if all the variables are working in our favor. We both know our antennas and equipment are working perfectly, so the only thing left would be propagation and weather. The way to determine this is to be persistent and continue to attempt making contact as we have been.
In closing, Ill speak on the dipole antenna... Regardless of the design, *any horizontal antenna that has a single radiator and a single radial* is by definition a dipole... same rules apply for a Carolina windom, off center dipole, G5RV, etc.. they are all dipoles and will basically have the same rules..
Dipoles: The ideal elevation for a dipole is the same as the distance from tip to tip. A 40m dipole will be 66 feet long, thus should be 66 feet above ground. A 20m dipole will be about 16 feel long, and thus need to be 16 feet above ground. When we bring the dipole down to a distance less than ideal, the take off angle rises... The lower you go, the more it rises. This principle is how we can take a simple dipole and make it work NVIS (Near Vertical Incidence Skywave). NVIS is for very short/close in communications.
My 40m dipole CANNOT be of the recommended elevation, it is mostly about 8 feet above ground (I know, pathetic, but its the best I can do!) so you can just guess how vertical the take off is! It wouldnt surprise me if it were modeled to be straight up into the sky!!
This is one reason, for me and my location, I prefer the vertical antenna, I get a lot better performance out of it just sitting on the ground, than I can with the best and most expensive dipole... Id never be able to get it in the air far enough for it to operate properly.
Thats all for now...
EB
RR: The short of it is: we will try some more! HA HA!
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Originally Posted by bacpacker
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