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If an antenna has a very low radiation resistance, does it indicate anything that needs attention? #AmateurRadio #HamRadio
in reply to vvbudh

@vvbudh
I had the same question. Now I'm going down a rabbit hole of: How would one actually measure / infer radiation resistance?

#HamRadio #AmateurRadio

in reply to Allpoints

@vvbudh I'll admit I didn't go far down that hole. Not surprising but I couldn't find any practical way to measure it.* The best one can do is a calculation/simulation and work off those assumptions.

In the end, the real world is too far from the ideal used in calculations. Just try for as long and high a radiator as reasonable.

*Perhaps one could measure the radiation of very small antennas and work backward but not practical below ?UHF?, or maybe higher?

#HamRadio #AmateurRadio

in reply to Allpoints

@allpoints if we’re talking about the same thing we could measure it with reverse beacon perhaps?🤔
in reply to vvbudh

@vvbudh a single signal strength report at distance doesn't account for radiation pattern or path losses. It's nice to know that you're getting the signal to that location but really doesn't tell you anything about how much energy the antenna radiated versus how much it dissipated as heat or other losses.

A dummy load can have perfect SWR and zero radiation losses. Measuring out how much energy is actually radiated from an antenna in all directions is difficult.