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LW1EAA > TODOS    26.10.17 15:03l 127 Lines 6483 Bytes #999 (0) @ WW
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Subj: VOACAP disc qrz
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Sent: 171026/1251Z @:LW1EAA.LP.BA.ARG.SOAM #:1921 [LA PLATA] FBB7.00e $:1921-LW
From: LW1EAA@LW1EAA.LP.BA.ARG.SOAM
To  : TODOS@WW

Is there any HF propagation software that takes the antenna pattern into consideration when propagation mapping? For instance, I simply don't care if Alaska has a great 20M opening, as I only have a dipole that is pointed towards the North East. In other words, all such programs I have encountered seem to be setup for only omni-directional antennas, which isn't very realistic unless you're into verticals... 

prop.jpg 

Thank you,


-Cotter
KZ3J, Apr 26, 2016 #1
 KB4QAA
KB4QAA
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Yes. The VOACAP is free government prediction engine software. It has a database of antenna models which are selected for predictions. You may create different antenna models using other software and install them in VOACAP.

You posted a capture of DX Atlas by Afreet Software. They also offer HamCAP, a graphic overlay which uses the VOACAP engine (as does DX Atlas-I believe). HamCAP has it's own set of antenna models.

Information on VOACAP can be found here: 

http://www.voacap.com/
Info and online VOACAP version.

Afreet Software, HamCAP -free- IonoCAP solar condition program is also highly recommended.
http://www.dxatlas.com/HamCap/

Creating antenna models for HamCAP and VOACAP
http://www.voacap.com/hamcap-type1314.html


L.B. Cebik, W4RNL on VOACAP antenna models
https://www.antennex.com/shack/Aug07/type-13.pdf

ARRL VOACAP Introduction and Tutorial
https://www.arrl.org/files/file/Technology/propagation/Voacap.pdf

Greg Hand's VOACAP distribution and information site with links. 
http://www.greg-hand.com/hf.html
Last edited: Apr 26, 2016
KB4QAA, Apr 26, 2016 #2
 KZ3J
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Thanks Bill, but doesn't that only work for a single circuit in VOACAP (say from KZ3J to KB4QAA), rather than showing a full propagation map that takes your antenna pattern into consideration? For instance, all the programs I have used so far only seem to have an omni-directional antenna pattern when the propagation is mapped, even when you select say, a dipole as your antenna. Or am I missing something important in these rather complex programs?
(BTW, you have some of the most beautiful "boat anchors" I have ever seen! Wow.)
GO_9_Glows_320_240.jpg
KZ3J, Apr 26, 2016 #3
 K4SAV
K4SAV
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The snapshot you showed is from HamCAP. It has an "Ant" tab where you can select the type antenna. The types are limited to Yagi, GP, dipole, or hex beam, at various heights. It assumes the antenna is pointed at the station. You also get to choose the type of antenna that the DX station is using. I suggest choosing something typical for the DX station on each band. You can also set the power level on the transmit end. 

No you don't get to choose an arbitrary fixed pattern, at lease with the built-in pattern selections. I know there are programs (like EZNEC) that can write a VOACAP file which can be added to HamCAP. I have not played with that so I don't know if Ham CAP (running VOACAP) will use that pattern as a fixed pattern for all 360 degrees or not. It shouldn't be too difficult to try it and see.

Jerry, K4SAV
K4SAV, Apr 26, 2016 #4
KZ3J likes this.
 K8JD
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If you have a rotary. directional antenna you are supposed to AIM it to where the band is open to. My fixed, directional, gain antenna (Wire EDZ) is aimed to Northeast/Southwest because that's where all the good DX I want to work is. (Europe/Hawaii, S. Pacific, VK. ZL.).
Those Propagation predictions are just a starting point, the rest is up to you.
K8JD, Apr 26, 2016 #5
KZ3J likes this.
 KB4QAA
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KZ3J,
VOACAP uses the 'best case' or highest gain figure to make the calculations for a point to point path. HamCAP (using the VOACAP engine and HamCAPs own antenna models) shows a graphic display of the max gain, not a true 360 degree representation of the antenna lobing pattern like EZNEC does.

Thanks for the kind remarks. You might note the glowing three light bulb 'dummy load" atop the navy GO-9 transmitter, which I have used to make contacts on 40m CW!
Last edited: Apr 26, 2016
KB4QAA, Apr 26, 2016 #6
KZ3J likes this.
 KL7AJ
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KZ3J said: ?
Is there any HF propagation software that takes the antenna pattern into consideration when propagation mapping? For instance, I simply don't care if Alaska has a great 20M opening, as I only have a dipole that is pointed towards the North East. In other words, all such programs I have encountered seem to be setup for only omni-directional antennas, which isn't very realistic unless you're into verticals... 

View attachment 293515 

Thank you,


-Cotter
Click to expand...
Proplab Pro 3. It is also the ONLY program that takes into account the Earth's magnetic field and plots the X and O rays independently
KL7AJ, Apr 26, 2016 #7
 KZ3J
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KL7AJ said: ?
Proplab Pro 3. It is also the ONLY program that takes into account the Earth's magnetic field and plots the X and O rays independently
Thanks KL7AJ, but the $240 price tag has always put me off, especially since I have never seen a 30 day demo for the program.
KZ3J, Apr 26, 2016 #8
 KL7AJ
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Let me drop a line to Tomas....he might be able to slip you one a bit cheaper.
KL7AJ, Apr 26, 2016 #9
 K4SAV
K4SAV
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KB4QAA said: ?
KZ3J,
VOACAP uses the 'best case' or highest gain figure to make the calculations for a point to point path. HamCAP (using the VOACAP engine and HamCAPs own antenna models) shows a graphic display of the max gain, not a true 360 degree representation of the antenna lobing pattern like EZNEC does.
Obviously VOACAP doesn't display a lobe pattern but that is not the question. The question s whether VOACAP has the option of using data for 360 degrees of azimuth.

The VOACAP file written by EZNEC contains elevation data points for each of the 360 degrees of azimuth. Seems to me there would be no reason to write all that data if there is no option of ever using it. Sure, you would want to use only one azimuth angle for a Yagi since you can rotate a Yagi. I have not tried this to see if VOACAP will align station azimuth directions with azimuth data in the pattern file, but if it doesn't have that option then 99.7% of the data in the pattern file is useless.

Jerry, K4SAV
Last edited: Apr 26, 2016
K4SAV, Apr 26, 2016

http://forums.qrz.com/index.php?threads/hf-propagation-software-that-uses-antenna-patterns.521228/


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