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Antenna Modelingsoftware

Ken Konechy W6HHC

Ken Konechy W6HHC 2

Antenna Modelingsoftware

• teaches you more about antennas• how to design better antennas• how to predict antenna performance • how to “tune” for performance• lets you try “what if….”

Ken Konechy W6HHC 3

“What is Antenna Modeling?”

• it is NOT making tiny models

• it is a computer program to predict and analyze antenna performance

Ken Konechy W6HHC 4

“What is Antenna Modeling SW?”

• Allows you to describe an antenna• Allows you to describe your antenna height• Allows you to choose construction materials• Allows you to describe your ground conditions• Allows you to analyze gain• Allows you analyze impedance / SWR• Allows you to predict “band-width”• Allows you to plot directivity & front-to-back

Ken Konechy W6HHC 5

Example of an Antenna Modeling Program

EZNEC Software Describing a 40M Inverted-Vee

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Another Example of an Antenna Modeling Program

NEC-Win Describing a 10M 2-El Beam

Ken Konechy W6HHC 7

Example of an Antenna Modeling Program

Select Material for a 10M Dipole

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Example of an Antenna Modeling Program

Select “ground conditions” for a 10M Dipole

• NO GROUND – “free space conditions”

• PERFECT GROUND – “ The perfect world is simulated”

• SOMMERFELD GROUND – “Choose many real conditions”

• REAL GROUND – “Complex, allows nearby cliffs, hills, etc.”

Ken Konechy W6HHC 9

Example of an Antenna Modeling Program

Select “Sommerfeld ground conditions”

Ken Konechy W6HHC 10

Example of an Antenna Modeling Program

Gain plots for a 6-EL 20M Beam

Ken Konechy W6HHC 11

Example of an Antenna Modeling Program

Predicting SWR for a 10M Dipole at 20ft

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Let us Explore a 10M Dipole

Gain plots for 10M Dipole over different groundsHeight = 20 ft

Ken Konechy W6HHC 13

Let us Explore a 10M Dipole

Gain plots for 10M Dipole at different heightsOver Sandy ground

Ken Konechy W6HHC 14

Let us Explore a 10M Dipole

Gain plots for 10M Dipole at 5 degree Elev

10.7 dB of the gain is lost at 5 degrees!!!!!!

Ken Konechy W6HHC 15

Let us Explore a 2-EL 10M Beam

Gain plots for 10M Beam at different heights

Ken Konechy W6HHC 16

Explore Antenna Model for 30M Dipole

“Shortened” 30M Dipole Design(Four sections of Aluminum tubing)

Ken Konechy W6HHC 17

Antenna Model for 30M Dipole

I wanted mast for 30M Dipole only 10-ft high(Horizontal dipole is a “cloud-warmer”)

Ken Konechy W6HHC 18

Antenna Model for 30M Dipole

Horiz Shortened-Dipole Vert Shortened-Dipole

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Antenna Model for 30M Dipole

Finished Construction of 30M Shortened-Dipole

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Antenna Model for 1.2 GHz “Panel”

Six Loops of wire are positioned over a

Mesh Reflector for basic Panel Antenna

Ken Konechy W6HHC 21

Antenna Model for 1.2 GHz “Panel”

Two sets of Six-Loop Arrays provide 3 dB More Gain for a Total of 17 dBd

Ken Konechy W6HHC 22

Antenna Model for 1.2 GHz “Panel”

Large 6-loop panel array byHA5IW mounted up on the Tower

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Antenna Modeling – “a lesson learned”

• While preparing a TechTalk on Panel Antenna, I corresponded with G8GML about gain

• In G8GML’s article in CQ-TV, he field tested the 6-loop design over mesh at 16 dBd gain

• My NEC-Win model showed 14 dBd ??

• G8GML kindly explained “ground reflection” at a test site can add to measured gain

• So in real world…“Your mileage may vary!”

Ken Konechy W6HHC 24

Different Antenna Modeling SW• NEC2 – was designed by Lawrence Livermore Labs

• EZNEC - uses NEC2 “core” software with Windows GUI

- by Roy Lewallen, W7EL - www.eznec.com

• NEC-Win – uses NEC2 “core” SW with GUI

- by L. B. Cebik, W4RNL (SK) - NO LONGER SOLD

• MINI-NEC – simplified NEC2 to run on slow PCs

- fairly obsolete, inaccurate

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Antenna Modelingsoftware

The End

Any Questions??