“High SWR is bad…antennas that show high SWR are inefficient and do not radiate well. So if my SWR is bad, no one will hear me”

The antenna does not have an SWR, the feedline does.

An antenna’s efficiency is determined by the ratio of its radiation resistance to its total input resistance. What goes in, should come out.

You can have a great antenna connected to a terrible feedline – it might be way too long, or full of water.

I would rather have a great feedline (balanced) connected to a terrible antenna – because I can still tune it to match, and it will radiate.

A dummy load has an SWR of 1.0 and it doesn’t radiate at all. A short vertical antenna with a radiation resistance of 0.1 ohm and a loss resistance of 49.9 ohms radiates only 0.2% of its input power, but has an SWR of 1.0.

What does SWR really mean?

SWR has very little to do with how well the other station hears you. It is only a reflection (!) of how happy your transmitter might be. Unhappy transmitters will not work hard.

Your SWR has nothing to do with how you sound to the other station. I often use antennas on completely different bands than those they resonate on, with the panel on the transceiver flashing “warning – high SWR.” (I dial down the power a bit, just in case.) I have worked many rare ones that way.

My favorite examples are the mobile antennas for HF – manufacturers fall all over themselves trying to convince you that their 6′ long antenna is going to be great on 75-meter sideband. As Scotty would say, “ya canna change the laws of physics, Cap’n!”

What you have is (relatively speaking,) either a very tiny antenna, or a large dummy load.

Don’t get me wrong – you can make contacts with a dummy load. I’ve done it. I’ve made contacts loading up a slinky too, but I don’t recommend it for everyday use.

The biggest antenna myth of all time
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