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Well, did the SWR analysis of my dipole using my NanoVNA and things aren't looking good. :(

  • 6m: SWR never drops below 10.
  • 2m: SWR is 2-3.
  • 70cm: SWR never drops below 3.

Now I'm wondering if the stucco walls several inches from either end are causing problems, since stucco contains a fine metal mesh. Or maybe it's this 9" turn of coax near the transceiver? :/

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Dipole antenna on the balcony with its sleeve balun meant for 6m
Each leg is ended like this, strapped to a long wooden rod
2 turns @ 9" of coax near the transceiver
NanoVNA showing bad SWR in 6m band
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in reply to Neil E. Hodges

hambitious
hambitious
• •
the walls are certainly having an influence. Anything close to the antenna that's metal or has water will.
in reply to Neil E. Hodges

Neil E. Hodges
Neil E. Hodges
•

Looks like the dipole likes much higher frequencies than I can really make use of with my transceiver. :P

#AmateurRadio #HamRadio

#hamradio #amateurradio
in reply to Neil E. Hodges

Comrade Weez
Comrade Weez
• •
What is the length? What freq were you intending it to work on?
in reply to Comrade Weez

Neil E. Hodges
Neil E. Hodges
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The total length is 3m and I'm trying to target the 6m band.
in reply to Neil E. Hodges

Comrade Weez
Comrade Weez
• •
for 52MHz, your dipole should be 2.88m. 3m will resonate ~49.96MHz. I would leave out the sleeve balun (disconnect it from the dipole & slide it down the coax) until you can see a nice tuning peak at 52MHz on your nVNA. The 50kHz-900MHz trace you have set up on your VNA pic is far too wide to see any detail, set your range to 50-54MHz. If you are near reflective objects like the screen in the stucco, it could cause a high VSWR. Let me know how you go.
in reply to Comrade Weez

Neil E. Hodges
Neil E. Hodges
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Thanks! I made the antenna easy to change the length of for a reason. :3

Here's the 50-60 MHz graph from the original post, by the way.

in reply to Neil E. Hodges

Comrade Weez
Comrade Weez
• •
hmm, your dipole would have been 2.65m for a resonance at 56.4MHz 🤔
in reply to Comrade Weez

Neil E. Hodges
Neil E. Hodges
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Someone I talked to elsewhere suggested a longer feed point insulator to lower the resonant frequency, so I'll also be trying that.
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