[guizmo1967]

Hi guys, this is my first post by the way !!!

Let's say I build a GH10 with narods and I would like to know the gain of this antenna once finish or any other models like a GH6 or GH4 etc....

Is there a device that I can plugged to the antenna that can give me the gain or some king of calculation ???

I want to khow that because I want to make some changes to the antenna and be sure that I'm making a better antenna not worse !!!!

Does the 4nec2 program give the gain ????

Thanks

 

[ADTech]

Generally, antenna gain can be determined two ways:

1) Mathematical modeling will give the "theoretical" gain.

2) Comparison of the test antenna's reception to the reception of a calibrated or characterized reference antenna using standard RF test equipment in a controlled environment.

4NEC2 will, if the antenna is properly modeled, give a "theoretical" gain values that should be "close enough for guv'ment work". Measurements at an antenna testing facility can be taken to validate the mathematical models.

Since antenna test ranges are both expensive and few and far between, that leaves modeling and "relative field testing" as the most common means available to the enthusiast.

 

[guizmo1967]

Ok, thanks for your anwers, it's understood now.

 

[300ohm]

Does the 4nec2 program give the gain ????

Yep, as noted above, it gives the theoretical dBi gain in free air space, if you chose the free air space option. Comparisons between antennas can only be fair in a free air space model, since local ground conditions can vary results a lot, whether by model or by field testing.