Bug in Antenna Optimizer v6.5 ?
Serge Stroobandt, ON4BAA
I have encountered something what appears to be a bug in Antenna Optimizer
v6.5.
Modelling a 70cm colineair antenna with stub and gamma match yielded
contradictory results in the 2D and 3D radiation patterns and gain.
I have included the 70COLIN.ANT file below for those who want to experiment
with it.
You will see that the 3D radiation pattern reports 4.99dBi gain. The 0°
elevation azimuth-plot yields an almost uniform gain pattern of 4.01dBi.
This is still ok, because the higher gain direction can be at a higher
elevation. The 0° azimuth elevation-plot is also still ok.
Plotting a 90° or 270° azimuth elevation-plots is what really produces the
most akward results with an asymmetrical end-fire pattern and a gain of
5.25dBi, not observed in the 3D-plot, nor the azimuth pattern.
Could it be that AO is assuming a symmetry that is not there?
Is this bug/problem known and has it been reported yet?
I tried to contact the author of this sofware, Bryan Beezley on k6...@n2.net
but unfortunately this email address does not seem to be active anymore. Has
anybody Bryan's new email address?
70cm Colinear
Free Space
434.971 MHz
8 copper wires, mm
wdiam = 12 ; antenna wire diameter
fdiam = 12 ; feeder diameter
elem = 338.1602 ; element length
stub = 142.5328 ; stub length
hshort = 30 ; half the short length
elstop = hshort + elem
1 0 0 -elstop 0 0 -hshort wdiam ; lower element
1 0 -stub -hshort 0 0 -hshort wdiam ; lower stub part
1 0 -stub -hshort 0 -stub 0 wdiam ; lower short half
1 0 -stub 0 0 -stub hshort wdiam ; upper short half
1 0 -stub hshort 0 0 hshort wdiam ; upper stub part
1 0 0 hshort 0 0 elstop wdiam ; upper element
1 0 -stub 0 0 0 0 fdiam ; feeder
1 0 0 -hshort 0 0 0 wdiam ; gamma
1 source
Wire 7, End1
--
PS: Please, send your comments to the newsgroup. As of tomorrow I will be on
a business trip for the next two weeks and will only be able to respond
occasionally. Hopefully, by the time I am back you guys have found / fought
it out all ;-)
73 de Serge ON4BAA - HB9DWU
propagation & ham info at:
http://salsawaves.com/propagation/
Bill VanAlstyne
> I tried to contact the author of this sofware, Bryan Beezley on
> k6...@n2.net but unfortunately this email address does not seem to be
> active anymore. Has anybody Bryan's new email address?
Serge,
I exchanged a couple e-mails with Brian in August at the address b...@n2.net.
Bill / W5WVO