Hello, I am trying HFTA, really very interesting the info from it. I model for different antennas, also for a stack of monobanders. BUT, how can I add a different antenna to this model? For example I
Jorge, HFTA assumes nominal gain figures for antennas containing a certain number of elements for a certain band. It does not model the performance characteristics of a particular antenna design for
No, it is not possible, I'm afraid. There's not yet any svh thing as a Swiss Army Knife that combines the terrain capabilities of HFTA with the antenna modeling abilities of NEC. Maybe some day... 73
Not good news, hi hi... HFTA is very easy to use, not NEC, at least for me.! Is incredible how an antenna vary with only few feets of height, I´m knowing some interesting things from my station. I ha
HFTA doesn't model antenna:antenna interactions, which is why the user instructions caution about putting antennas too close together. (because at small distances they DO interact, and HFTA ignores i
The REAL Swiss Army knife for antenna modeling would, in my opinion, combine the terrain analysis of HFTA with the antenna modeling capability of NEC .... and do it for both transmit and receive. I r
I don't know about that... That would imply a violation of reciprocity, wouldn't it? I would believe non-symmetric propagation via skywave, but not that the "effective antenna pattern" is different f
Not necessarily. See below. The word "effective" is an important qualifier here. What HFTA does is attempt to model interaction of the wavefront with terrain. So it isn't the antenna pattern that's c
No ... it doesn't really have anything to do about propagation reciprocity through the ionosphere. It is all about non-symmetry of terrain. As a simple example, picture a tall distant peak with a sho
If you think about your example of the two ground peaks at different heights, what would the shadow of the larger one have to do with direction? If the receive path has the small peak in the shadow o
I suggest that you do two things: 1. Read the extensive discussion of terrain interaction in general and HFTA in particular in the ARRL Antenna Book. 2. Generate some sample terrain plots see for you
Not necessarily. See below. The word "effective" is an important qualifier here. What HFTA does is attempt to model interaction of the wavefront with terrain. So it isn't the antenna pattern that's c