Hi Vernon this might tend to prove that the simulation is not modelling the travelling wave effect that gives the long low wire is directional preferences (??) Alan G3NYK on the whole 1000' is N/S
Hi Rik isn't it more likely to be the case that these low antennas are much more dependent on ground conditions, which are not modelled very well (or at all) in any of the simulators. In many cases t
In a message dated 22/01/2008 14:00:59 GMT Standard Time, [email protected] writes: I simulated the fence wire with MMANA. On HF (80m, 40m) I got the expected (bi)directivity and low offset
Hello LFers & Lowfers, I've been testing a 1200 foot end fed longwire mounted on an existing fence-line and coupled to the receiver with a 3:1 turns ratio isolation transformer. The antenna is 3 feet
Rick that is surprising as I find them very directional and that the 1000' on the whole has worked better than the 2000' but that could just be propagation. The 1000' is N/S and the 2000' is E/W. Any
yes trees will work as lf antennaes..not recomended for trans mitting though ..not in clean green new-zealand...different ways to couple into trees using ferrite rods....a good sniffer on lf is a few
Hi Mike the problem with this is it becomes a narrow band antenna which is not what JB wants.....It also destroys its action as a "travelling wave" antenna. It will then be a heavily top-loaded but v
more dependent on ground conditions, which are not modelled very well Highly likely! This is one of the things that has become painfully obvious to those of us interested in cave radio. To add to th
EZNEC 5 shows the 1200 fence (3ft hi) antenna to have remarkable receive properties If terminated with 400ohms it produces a polar diagram not unlike a 3-element Yagi with a maximum gain of -17dBi an
What if JB put a big loading coil in the fence wire? I would think that would work just like our loaded short verticals...Sure there would be losses but we have losses in our transmitting antennas al
Johan, indeed there are some limitations to MMANA. And when getting a negative radiation resistance one should get cautious. But for small verticals and small loops MMANA seems to work OK. I am using
Hello all, In practice even a short in regards of wavelength wire on the ground shows good directivity. A 100 m long untermintated wire on the ground is already an excellent antenna from 250 kHz and
Vern, almost omnidirectional and 90 degrees takeoff. But don't believe too much of that. 73, Rik ON7YD I use a 2000' and 1000' unterminated longwires that simply lay on the ground and are used specif
J.B. , I simulated the fence wire with MMANA. On HF (80m, 40m) I got the expected (bi)directivity and low offset angle. But on 500kHz the horizontal pattern is almost omnidirectional and the offset a
Hi Peter, Rik, LFers, Thanks for modeling my fenceline longwire and sharing the results. I appreciate any input/comments on the antenna, but I have to say that I'm rather surprised that nobody questi
Hello Rik, MMANA works very well for free space models but since it is based on MiniNEC, it does not properly model how the "real world" ground interacts with the near field. As far as I know, it use
Hi, When I first got interested in radio "when I were but a lad", an old G2+2 who "elmered" me once suggested that "when all else fails cover the sky with wire". I have often found over the years a l
HI Rik... I use a 2000' and 1000' unterminated longwires that simply lay on the ground and are used specifically for 500khz and down. I have been very impressed with their performance on NDB's etc. B
I have been testing some real barbed wire fences of 1500 metre long, which showed a very narrow beamwidth in one direction. If you have the opportunity, there are many usuable fences out there which
