Resonant vs. nonresonant antenna's

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Frank van Wensveen:
DR OM's,

What are your thoughts about resonant vs. nonresonant antenna's? I know hams who swear that unless an antenna has precisely the right length (either physically or trapped) to be resonant, it's useless. I also know hams who claim that any dipole will do, the longer the better (within reason) as long as it's fed via a symmetrical feed line and connected to a proper antenna tuner.

I've used both with good results, and I really haven't found one to be consistenly better than the other. In fact I tend to put up an antenna the length of which is determined by the distance between whatever end points are convenient, I feed it via a ladder line and tune it using my trusty old MFJ portable tuner.

Without wanting to start a holy war on this subject... what are your points of view? Is resonant better than nonresonant, or is long-and-nonresonant better than short-and-resonant?

73 Frank PA3GMP/ZS6TMV

Bob Lewis:
There is absolutly no difference between the performance of a resonant and a non-resonant radiating element provided it is fed properly. Those who have bad experiences with non-resonant antennas probably tried to feed it with coax cable and a tuner at the far end. The mismatch on the coax causes a lot of loss which limited the performance. Feed it with low loss cable like open wire or put the tuner directly at the feed point and a non-resonant antenna will work find.

Actually, the tuner will tune any antenna "system" (radiating element plus feed line) to resonance just like inserting a loading coil into the element will tune it to resonance.

Clint Talmadge:
You can make contacts on either type of antenna, HOWEVER..  A non-resonant antenna means you can not tune to a frequency and start talking or sending CW.  You must tune the antenna system which takes time.  You can tune it on the air after trying to find a clear frequency close to the one on which you want to operate or use some external means such as a Palomar Tuner-Tuner or switch in a MFJ-259 (that is what I do). There are some automatic systems such as the Icom AH-4 or the SGC line that tunes the system for you, but remember it still takes some time. If you have any aspirations to do any contesting, a resonant antenna system is a must as you will be hard pressed to find a clear freq on which to tune.

Above all remember the first rule of Ham Radio which is "RF gotta go somewhere!"

Clint - W5CPT

"If you have any aspirations to do any contesting, a resonant antenna system is a must as you will be hard pressed to find a clear freq on which to tune. "

What about switched matching networks?

Not resonant on any band I use it on, but works quite well, and I don't have to do anything other than twist one knob, just like an antenna switch.


Gunter Lindermeier (Lindy):
The best way is to put an antenna analyzer in line with a switch, the radio/amp to antenna tuner. You can tune up very fast and if you have a graphing analyzer, you can see how far you can move off and still have a good match. No QRM involved!

73, de Lindy


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