Quick Yagi Antenna Design Software



Paul McMahon VK3DIP

News andReleases

What isYagiCAD

WHATYAGICAD WILL NOT DO

Lightweight program that provides users with a simple means of calculating various parameters pertaining to your Yagi-Uda antenna YAGI is a software application whose main purpose is to help you. Yagi-Uda Antenna theory, design, Simulation on Software.

YagiCADis FREEWARE

History

Installingand Removing YagiCAD

Screenshots

GeneticOptimisation In YagiCAD

YagiCAD Tips, Tricks, andExamples

Downloads

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YagiCAD News

New YagiCAD 6.2.7

Changes 6.2.6 to 6.2.7 August 2019
1. Beta version of multi band optimization in OWA Genetic tool, please report any problems.
2. Bug fixes to fix occaisional crashes due to even numbers of segments.
3. Corrected problem with reference yagi gain, now shows in same units as main gain.

Bugfix YagiCAD 6.2.6

November 2018 6.2.6 Bugfix.

1. Fixed bug with options not saving/loading correctly. replacement 6.2.61 exe (zipped) Here

Changes 6.2.5 to 6.2.6 August 2017.

1. Added mm (MilliMetres) as a units option.

2. Some minor changes to limits in antenna temperature figure of merit calculations.

3. Added limited export to EZNec format file. Thanks to Roy Lewallen for his permission and for the file details. Only the very basics are exported to try and limit problems. Please report any issues to me.

4. Redo of boom correction support, can now edit in either length or length+bcf columns, now need to use options menu to vary custom BCF.

5. Updated version of Nec-Tie included, fixed some bugs with loads support in MiniNec, also added import from EZNec format files. Thanks again Roy.SeeNEC-TIE page for more info.

6. A number of minor cosmetic changes.

YagiCAD 6.2.5

Changes 6.2.0 to 6.2.5 catchup release August 2015.

1. Updated TEE match calculations to be in line with equations in latest versionof 'Playing with Matches'

http://www.yagicad.com/Projects/PlayingWithMatches.htm

2. Changed Antenna temperature tool nomenclature to be as per RainerBertelsmeier's Effective Noise Temperatures of 4-Yagi-Arrays for 432 MHz EME inDUBUS 4/87.

3. Added a number of other possible element material types such as 6063-T832, and6061-T6 Aluminium alloys as per common usage.

4. Added Antenna notes window, via Tools menu, for multiline/longer notes on adesign.

5. Included stand-alone NEC-TIE app in main YagiCAD directory, also available fromTools menu, that can import NEC(most nec2 and 4nec2 nec), YW(.yw), YO(.yag), MNand AO (.ant) style files and amongst other things convert them (if theyare Yagi's) to a monotaper yagi and save in YagiCAD (YC6) format. Getting allthose designs from the ARRL antenna book etc. should now be easy. Also includesnative double precision mininec, and antenna viewer. Version 1.0 of NEC-TIEcomments/bugs welcomed. SeeNEC-TIE page for more info.

6. A number of minor cosmetic changes.

YagiCAD6.2.0

April 2014

1. Changed internally and for export to have Yagi boom along X axis to align withcommon usage.

2. Added antenna temperature tool to toolbox which does a basic noise calculationbased on the DUBUS article by Rainer Bertelsmeier, DJ9BV “Effective NoiseTemperature of 4- Yagi-Arrays for 432 Mhz EME”. This produces similar resultsto the TANT program by YT1NT.

3. To validate the antenna temperature figures, or for other post processing usesthere is now also an export option for a far field table in an appropriateformat for TANT.

4. Added the ability to have two more folded dipole element variants, these aresimilar to the existing folded dipole however they are in the plane of the boomrather than perpendicular to it. One variant is laid down forward ie. Drive iscloser to the reflector, while the other variant is laid backwards, ie. Thedriven side is closest to the first director. These configurations aresometimes known as LFA. See the included example model 13e23cmLFA.YC6 as anexample of what can be achieved with this configuration.

5. Added option on tools option form to select calling a NEC engine via a command(or BAT) file or directly (default.). The default direct call to nec2++.exe isfaster and automatically handles whatever the number of segments. The commandfile option however allows the use of other standard nec executables if youhave a favorite. Examples for some of these are included in the necrun.cmd filein the root install directory. (Unused ones should be prefaced by a REM). Ihave not tested this with NEC4 (as I don't have access to it) but it shouldwork. Please let me know if anyone finds any problems with this.

6. A few other mostly cosmetic tweaks.

YagiCAD6.1.9

November 2013

1. Added ASCII text export of model for codes that don't read nec files.

2. Bug fixes around boom correction factors, now entry of custom BCF is always anumber less than 1. Also clarified for the built in correction factors that oneis for the element insulated from the boom case (Ins), and one is for theelement connected to the boom (Con) case.

3. Rejig of the Gamma, Tee, Omega etc. matches to align with the ARRL and otherinterpretation of how these matches work.In particular now based on the full driven element impedance rather than halfas specified in Balanis textbook. My local tests with NEC2 models of Gammaagree that, while no simple model is particularly close to what you get fromthe more complex NEC2 model, those with full element impedance are closest.Also at least now YagiCAD should give the same answers as ARRL GAMMA program.

4. Changes inside the genetic algorithm to try to detect and kill'cancerous' yagi's where gain is unreasonably high which can maskreal improvements in rest of gene pool. Unreasonable high gain usually due to,elements with too close spacings, and other known model limitations withinNEC2.

Quick

4. A few other mostly cosmetic tweeks.

New Version 6.1.8

April 2011

1. Added 4NEC2 specific export support under file/export menu. 4NEC2.nec file willcontain symbolic variable extensions as supported by 4NEC2 to assistwith easily changing Yagi variables like antenna height.

New Version 6.1.7

February 2011

1. Added limits concepts into GeneticOptimisation.Can set a hard, soft, or no limit for each Target value. Hard =reject designs that better this target Soft = keep but limit score, None = donot limit score.

2. Added Boom length as a parameter inGenetic Optimisation. eg setting Boom Length Limit to a particular length, witha hard limit type will force only designs with Boom Length less than this valueto be considered.

3. Changed default install directory to benot program files to avoid problems with Windows Vista and 7 and admin rights.

4. Minor bug fixes with units in matchingsections.

5. Released companion XLS spreadsheet fortapered elements.LeesonTaper.xls in main install directory.

Version 6.1.6

January 2011

Bug fix release.

Design

1. Fixed a bug that had got into theGenetics bits that was causing unpredicatble results.

2. Added config file for frequency bandedges. If found 'banddata.txt' in main directory is used rather thandefault Australian ones. see example file for format.

Version 6.1.5

March 2010

Changes 6.1.5

  1. Replaced Fortran based NEC2SX/DX engine with Open Source C++ version of NEC2.(Compiled using free MS C++ 2008 Express)
    • No arbitrary segment etc. limits just available memory limits
    • Double precision only
    • Depending on CPU can be 2-3 times faster on large models.
  2. Added new element models of folded dipole and multi-element
  3. A few minor bug fixes.

Added YagiCAD Tips Tricks and Examples Page Here

Minor release 6.0.2

December 2009

Changes:

· Added support forcountry specific decimal point value, and in particular ',' in steadof '.' Thanks to Noel ON5 Ui

· Minimum of VSWR graph inOverall now 1 rather than 0.Thanks to Scott VK2AET

· A couple of minor bugsfixed.

· Install package whichregisters file types and creates shortcuts etc.

New Version 6.0 with Quads and Quagy’s

December 2009

Changes:

· Re-written using the freedevelopment package Microsoft VB.NET Express 2008. More Windows standardinterface, now requires MS.Net runtime 2.0 (for pre Win XP) or 3.5 (for postWin XP) rather than VB5 runtime as per YagiCAD5.x

· Removed YagiCAD classicengine, now only NEC2 available but choice of SX (single precision as inYagiCAD5) or new DX Double precision.

· NEC2 engines recompiledwith larger limits now allowing up to 40 elements, 2000 segments, or 100non-ideal wires, whichever limit is reached first.

· Still only a singledriven element, but it can now be in any position in antenna from first tolast. Ie antennas of a single driven element are now possible, eg dipole, aswell as ones with multiple reflectors.

· Elements can now beeither a simple dipole, or a square quad shape. Elements can be setindividually to each type allowing for various combinations giving standardYagi’s, Quad’s, or Quagies

· Dimensions used fordisplay and editing can now be set to be in Metres, Inches, or Wavelengths. Allinternal calculations and saving of data is done in Metres.

· New file extension“.YC6” used to save antennas with new features, YagiCAD can stillopen/read “.YAG” files but not save them as other than “.YC6”.

· The YagiCAD6 exe nowaccepts a filename as a command line parameter enabling “.YC6” and “.YAG” filesto be associated in windows with the exe for double clicking on a file andopening in YagiCAD.

· New Yagi Viewer menu togive 3D view of antenna model under design.

· Simplified and expandedgenetic Optimization subsystem. Configuration of options now done by selectingoptions on a page rather than editing a text file. New options include improvedweighting process with optional reference/normalization to either the ancestorantenna or some idealized target.

· Improved Model testswith segment convergence now graphed within the application to show effects ofincreasing segments, and in addition inclusion of the standard Average GainTest.

· A number of other visualtweaks, oh and yes it’s still free, however it is a .0 release after a majorrewrite so there may well be bugs etc. I haven’t yet found so take some care tomake backups etc.

New Version 5.2 with Genetic wideband optimisation

December 2007

New in version 5.2

Quick yagi antenna design software for beginners

· Genetic wideband multiparameter optimisation.

· Some new OWA basemodels.

· A number of minor fixesand tweaks.

Updated Version 5.1

September 2006

New in version 5.1

· More Match Options.-Hairpin, Omega, Capacitive.

· Many minor fixes andtweaks.

Initial Windows Release Version 5.0

November 2003

Version 5.0

· Native 32 bit Windowsfull Graphical interface.

· Optional use of includedNEC2 for calculations.

· Copy and paste to otherWindows applications.

· Export models and datato Nec 2, and CSV.

Re-Release of Version 4.2 on the internet.

July 2003

Initial Release of Version 4.2

April 1991

· Directivity as well asGain/FB/Sidelobe etc. optimization now available.

· Initial entry of dataproceedure reworked to be easier to use including new clear option if youreally want to start from scratch, plus defaults for all entries.

· ESC key now exits/abortsmost processing and returns you to the menu. No more waiting if you just askedfor the analysis of the wrong thing.

· Improved Errorhandling/reporting. Instead of errors flashing past on line 25, a pop up boxwill tell you what is going on, and you will have to hit a key to continue.

· Several bug fixes.

What is YagiCAD.

Yagicad is a fully integrated analysis anddesign package primarily intended for VHF yagi aerials.

Pdf

With Yagicad it is possible to enter a basedesign from scratch or use one of a number of saved well known designs. Thisdesign can then be optimised or scaled to suit particular requirements. Oncethis has been done a matching unit can be estimated and overall performancecharacteristics can be calculated and displayed graphically. Also available areradiation patterns and hardcopy print-out of results. Allowances in an analysiscan also be made for element cross sections other than simple circular ones, aswell as boom mounting techniques.

WHAT YAGICAD WILLNOT DO.

THIS PROGRAM IS BASED ON A THEORETICALMODEL OF A YAGI ANTENNA, MANY

ASSUMPTIONS AND SIMPLIFICATIONS HAVE BEENMADE. THE RESULTS OBTAINED

WITH THIS PROGRAM MUST THEREFORE BE TAKENWITH SOME CAUTION. IN OTHER

WORDS IF YOU BUILD AN ANTENNA THAT HAS BEENDESIGNED WITH YAGICAD

DON'T EXPECT TO GET IT WORKING EXACTLY ASCALCULATED WITHOUT AT LEAST

SOME EXPERIMENTAL ITERATIONS. IE. YAGICADIS NO SUBSTITUTE FOR A VSWR

METER ETC., AND AT LEAST SOME TRIAL ANDERROR. ANYONE WHO DOESN'T AT

LEAST USE A VARIABLE CAPACITOR OR HAVE SOMEMEANS OF VARYING A GAMMA

ARM LENGTH IS EXPECTING TOO MUCH FROM THISOR ANY OTHER ANTENNA

PROGRAM

Yagi Antenna Design

YagiCAD is FREEWARE

Unlike earlier versions of YAGICAD whichwere released under a shareware banner (not that I ever made any money out ofthem) this latter version 5.0 and on are presented free. I offer it to theworldwide community of antenna experimenters in part repayment for the adviceand invaluable input I have received from them over the years. It is my hopethat it will be useful to them and also help to introduce new people (andespecially radio amateurs) to the joys of antenna experimentation. I do howeverretain the copyright, and if someone wanted to include this program in somebook or software collection I would appreciate being at least asked first. Ican be contacted at the address below. Similarly if you have any comments or feedbackplease feel free to email me. I can't guarantee a speedy reply but I probablywill get there eventually

History.

Its a small(strange) world.

Back in 1987 I wrote the firstversion of YagiCAD based on some earlier programs I had done for one of the preIBM PC machines called a Microbee.. As this was pre-internet days I releasedYagiCAD via the medium that was available at the time which was Compuserve.There were several versions, up to the last one I did in 1991 which was YagiCADversion 4.2 (yes not 4.1). Up to version 4.2. these early versions usedthe wonderful tool from Microsoft called Quick Basic that I had purchasedduring a trip to America, this was initially version 3 but for later versions Iupdated to 4.5.

To be honest I then pretty much forgotabout it because:

1/. The motivation for the programwas to fill a gap between cookbook style programs and the more full blown(mini)NEC style ones that, at the time, needed much more machine grunt than Ihad access to, a 386 was a powerful machine in those days. This lack of machinegrunt very quickly went away, and NEC style programs became much morepractical, even if still not very friendly.

2/. I obtained very little feedback andthere seemed to be a large number of competing offerings.

3/. I got distracted with Work and Familyetc.

So I was very surprised in June 2003to come across, while looking for something else on the Web, a file calledYagiCAD, which sure enough was my program, but strangely it was version 4.1, aquick search with Google etc. yielded several sites which mentioned the programbut again all were version 4.1.

Anyway, after some effort to find a machinewith a 5.25 inch disk drive on it to read some old backups, I confirmed thatindeed the latest version that I did back in 1991 was version 4.2. As faras I can figure someone back then must have got version 4.1 off Compuserve, andsubsequently not got the 4.2 version, perhaps the 1st of April builddate put them off, but anyway at some stage that 4.1 file was loaded onto theinternet and it has gone on from there.

Anyway I tried to contact some of thesites to let them know about the later version but had variable success.

Having got the idea that some peopleobviously liked the program, I got enthused about YagiCAD again andsubsequently produced a windows version released in late 2003. This version 5.0release as well as being windows based also took advantage of the drasticincreases in machine performance to add a version of the full NEC2 calculationengine as an option. The program retains the original very much simpleroriginal YagiCAD engine for backwards compatibility, but unless you have a veryslow machine it is best to use the NEC2 one. For comparison the original engineused only one segment per element, the NEC2 one runs fine on most current machineswith more than 30 segments per element.

Installation andRemoval

Automatic Install – Setup.exe

If you use the version with the Setupprogram then there is nothing to do other than run the setup exe, and answerthe questions. This will do all the items indicated below for the manual setupexcept for the installation of the dot net framework if required. There will bea menu item on the start menu to uninstall if required or the control panel addremove programs process can be used. Note when installing to Vista you may needto be logged on as an administrator.

Manual Install. – YC60dist.zip

Save all the files of the distribution in asuitable directory. The EXE’s, OPT, GEN, and RTF file/s should all be in thisdirectory. The saved antenna models can be in the same directory or elsewhereif more convenient.

If you don’t already have the MS DotNetframework installed this can be downloaded from the Microsoft.com website andinstalled as per instructions. For PC’s with operating systems prior to WindowsXP the file you are looking for is Dot Net Framework 2.0 Redistributable, forthose with Windows XP or better the 3.5 version is the way to go.

You can create an icon on your desktop torun YagiCAD by right clicking and dragging the exe to the Desktop and selectingcreate shortcut here.

You can also in a file view window selecttools/folder options/file types and associate the “.YAG”, and “.YC6” extensionswith YagiCAD.exe. Or alternately simply double click on a “.YAG” or “.YC6”file and select program to open with as being YagiCAD.exe.

Manual Uninstall,

YagiCAD makes no changes to the registry(other than associating .Yag/.Yrc files), nor (apart from the DotNet runtimementioned) are there any files installed outside the original directorycreated. So just delete the directory created for the install if you don’t wantit anymore.

From version 5.0 on YagiCAD is now awindows application and should work on all 32 bit windows versions 98 and up.There are some limitations with the dot net framework, as mentioned earlierdotNet 2 is the latest version stated as usable on 98/NT/ME etc, dotNet 3 comespreinstalled on Vista.

Screenshots ofVersion 6.

Downloads

Quick Yagi Antenna Design Software

Version

Download Link

YagiCAD 4.2

YagiCAD 5.1

YagiCAD 5.2

YagiCAD 6.02 Just the files

YagiCAD 6.02 Setup Program

YagiCAD 6.1.5 Just the files

YagiCAD 6.1.5 Setup Program

YagiCAD 6.1.6 Setup Program

YagiCAD 6.1.6 Just the file

YagiCAD 6.1.7 Setup Program

YagiCAD 6.1.7 Just the files

YagiCAD 6.1.8 Setup Program

YagiCAD 6.1.8 Just the files

YagiCAD 6.1.9 Setup Program

YagiCAD 6.1.9 Just the files

YagiCAD 6.2.0 Setup Program

YagiCAD 6.2.0 Just the files

YagiCAD 6.2.5 Setup Program

YagiCAD 6.2.5 Just the files

YagiCAD 6.2.6 Setup Program

YagiCAD 6.2.6 Just the files

YagiCAD 6.2.7 Setup Program

YagiCAD 6.2.7 Just the files

If you have any feedback on YagiCAD pleasesend me a message at mailto:Ihatespam@yagicad.com

Please note you need to replace “Ihatespam”with my callsign to get my actual email address.

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So what's new in 2020, in Ham Radio Antenna Designs?


In the past several years, especially in the VHF/ UHF community, a new somewhat confusing method of rating antennas has appeared on amateur radio websites. This is the newest way the cutting edge designers are looking at Ham Radio Antenna Design.
Instead of the conventional means of DB gain or DBI gain , a new G/T table has appeared and copied across websites. At first glance this 'table' seems very intimidating to the antenna shopper. However its not really that much different then looking at accurate ( not manufacturers ) DB gain tables.
So what is this all about? Well first there is a concept called Antenna Temperture. Again this is a Concept. Basically the Earth and Atmosphere create a noisy environment around your antenna. Everything makes noise, The Sun, The Moon, The Sky itself, The Earth, as well as a myriad of Man-Made noises. (Led lights, Plasma TV's, Washing Machines, CATV, etc, etc.) Most unaccountable for.
So Antenna Temperture is not the Physical Temperture of your antenna, it is a relative idea of the amount of noise your antenna will hear. Or better yet a rough guide to the Signal to Noise ratio.
VHF/ UHF experimenters with antennas noticed that at those frequencys, antenna design can be optimized to provide a lower Antenna Temperture or theoretical lower Noise Floor. Since alot of this work was done by weak signal EME guys who would have their antennas pointed up at the sky, various angles were considered for rating the Antenna Temperture.
The somewhat majority consensus that they came up was 30 degrees of elevation would be fine for rating antennas. This is by no means a solid consensus, But basically an angle had to be picked , so this one got the nod.
Antenna Temperture is rated in kelvin degrees. I am not a fan of this, since many amateurs assume that these ratings coincide with actual tempertures at the antenna. This is the newest way of looking at Ham Radio Antenna Design.
But Hey I didn't come up with this concept in the first place.
If you are really interested in the details you can have a look here: HEREThis dates from 2012.
The G/T System is a measure equal to Signal/Noise ratio at the speakers of our radio. The Antenna is first thing in the Receiving chain. Next would be the Coax and any connections before your Rig, as these have loss, and in fact sometimes contribute to increased noise. Adding to the confusion about this table is there is also 'internal noise'. The noise generated by the antenna itself ! So what you want to look for
basically is this the lower the total K number (kelvin degrees) the better, and the G/T column is just the normal db gain of the antenna divided by the antenna temperture. The higher that number the better. Its all about finding your best ham radio antenna. The more bang for the buck so to speak.
So what about the Antennas? How different are they?
The Yagi or Cubical Quad antenna is effective at lowering the noise floor on any frequency, by having most of its radiation manipulated to one direction, and hopefully into one lobe. This mean cancelling all lobes except those in the main direction the antenna is pointed at, to achieve the lowest noise possible. That also means side lobes, back lobes, lobes at higher elevations, etc.
How does this differ then just DB gain?? In earlier commercially made antennas, the biggest concern was forward DB gain, without regard to whether their might be a weird 9 db gain side lobe hanging off the back corner of the antenna. Most earlier antenna designs had all kinds of stray lobes, some good front to back ratio, some poor front to back ratios. It didn't really matter.
I mean most people just look at DB gain, and know nothing else on how to rate an antenna, even if that figure itself is terribly inaccurate, that's just
all they know. So for the commercial antenna manufacturer the only number that mattered is / was.......DB GAIN.
So now clever amateur radio operators in the weak signal arena, have come up with better ways to design antennas that have good gain as well as low noise. After all you have heard of the Ham Radio Saying:
'If I can hear em' I can work em' . Well until a few years ago no one paid much attention to hearing them, or at least how to hear em' better. Most of the advances occur in the UHF world first in amateur radio because those antennas can be built and put up on air, within hours from start to finish. So testing results from dozens of antennas can be done in just days or weeks! Where as on HF putting up one 3 or 4 element yagi once in a lifetime is usually the norm. So VHF/UHF guys can find out results through different designs much faster then the HF crowd. However all antennas are scaleable by nature, so if you design a 4 element hi-tech Yagi on 2 meters with 11 DB gain, it translates directly into a 11 DB gain Yagi on 20 meters. Just alot bigger. So anything design advances done on 2 meters or above are completely valid on the HF bands.
So 'Low Noise' Yagi's and Quads that you may start hearing about soon in advertisements, are just newer designed antennas taking advantage of recent computer design , which can predict with decent accuracy how an antenna might perform in the real world. So how much better are these antennas?? Well on HF, certainly the lower the noise figure the better. On the higher UHF frequencys these differences in Antenna Temperture

can mean a difference of 10 or 20 db gain of lower overall noise. Thats alot. A real lot and critical in weak signal work and on the 432 mhz band.
Remember that old saying 'The Cubical Quad hears better and has less noise then the Yagi'. Well interesting enough those 100's of reports by Cubical Quad owners were not incorrect! The Weak Signal crowd has confirmed in that attempting to produce the quietest antennas they can, the Loop Fed Yagi and the Cubical Quad in fact DO have lower noise figures then conventional built Yagis! There is a point however in the UHF world where
building a 20 element Yagi on a 20 foot boom is alot easier , simpler and lighter then building a 20 element cubical quad. So there is a trade-off you have to make in Gain, Noise and complexity versus simple to build Yagi's.

Yagi Antenna

However on the HF bands where commonly 3 to 5 element beam antennas are used, the Cubical Quad Antenna's higher db gain reputation as well as the lower noise to your reciever was not a misnomer, but in fact it is now easily confirmed through the latest computer software and 2 meter antenna designers. Yagi's however will always be the simpler antenna to build and maintain. Especially on the lower HF ham radio bands 15, 20, 40 meters.

Yagi Antenna Design Software


Quick Yagi Antenna Design Software Download

The Bottom Line is this:
The newer 'Low Noise' Yagis and Cubical Quad antennas now just being produced commercially pick up less noise.
This means more signal for you. Or in G/T terms: a lower noise temperture.


Yagi Antenna Design Calculator

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