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added some more detail about my antenna
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lornop
lornop
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I keep hearing the recommendation to make your SWR as low as possible and that would imply good tuning.

I'm a new HAM and made a centre-fed half wave fan, 40m, 20, 15m. It works, and pretty well.

I tuned it with a NanoVNA and the SWR is about 1:1 - 1:2 for all bands I use.

But I suspect there's more to tuning than just SWR.

  • Is the perfect antenna going to be (50+0j) Ω?
  • Is it the imaginary part that changes the SWR?
  • How do you get a piece of copper wire to change its resistance to get to 50 Ω if its not?
  • How does all this fit together?
  • If I mess with it enough, am I ever going to get close to (50+0j) Ω?
  • Should I even care, if it works pretty well as is?

Edit: Its an inverted V on top of my house. The V is about 120 degrees.I have a 1:1 balun at the feedpoint.

I keep hearing the recommendation to make your SWR as low as possible and that would imply good tuning.

I'm a new HAM and made a centre-fed half wave fan, 40m, 20, 15m. It works, and pretty well.

I tuned it with a NanoVNA and the SWR is about 1:1 - 1:2 for all bands I use.

But I suspect there's more to tuning than just SWR.

  • Is the perfect antenna going to be (50+0j) Ω?
  • Is it the imaginary part that changes the SWR?
  • How do you get a piece of copper wire to change its resistance to get to 50 Ω if its not?
  • How does all this fit together?
  • If I mess with it enough, am I ever going to get close to (50+0j) Ω?
  • Should I even care, if it works pretty well as is?

I keep hearing the recommendation to make your SWR as low as possible and that would imply good tuning.

I'm a new HAM and made a centre-fed half wave fan, 40m, 20, 15m. It works, and pretty well.

I tuned it with a NanoVNA and the SWR is about 1:1 - 1:2 for all bands I use.

But I suspect there's more to tuning than just SWR.

  • Is the perfect antenna going to be (50+0j) Ω?
  • Is it the imaginary part that changes the SWR?
  • How do you get a piece of copper wire to change its resistance to get to 50 Ω if its not?
  • How does all this fit together?
  • If I mess with it enough, am I ever going to get close to (50+0j) Ω?
  • Should I even care, if it works pretty well as is?

Edit: Its an inverted V on top of my house. The V is about 120 degrees.I have a 1:1 balun at the feedpoint.

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added 23 characters in body; edited title
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Marcus Müller
Marcus Müller
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DIY 40m Antenna -tuning: RLC and SWR

Been searching for an answer for antenna tuning. I keep hearing the recommendation to make your SWR as low as possible and thatsthat would imply good tuning. Im

I'm a new HAM and made a Centre fedcentre-fed half wave fan, 40m, 20, 15m. It works, and pretty goodwell. 

I tuned it with a NanoVNA and the SWR is about 1:1 - 1:2 for all bands I use. 

But, I feel like theressuspect there's more to tuning than just SWR. Is the perfect antenna going to be 50ohm+0j ? Is it the imaginary part that changes the SWR? How do you get a piece of copper wire to change its resistance to get to 50ohms if its not? How does all this fit together? If i mess with it enough am I ever going to get close to 50ohm+0j ? Should i even care, if it works pretty good as is?

  • Is the perfect antenna going to be (50+0j) Ω?
  • Is it the imaginary part that changes the SWR?
  • How do you get a piece of copper wire to change its resistance to get to 50 Ω if its not?
  • How does all this fit together?
  • If I mess with it enough, am I ever going to get close to (50+0j) Ω?
  • Should I even care, if it works pretty well as is?

DIY 40m Antenna - RLC and SWR

Been searching for an answer for antenna tuning. I keep hearing to make your SWR as low as possible and thats good. Im a new HAM and made a Centre fed half wave fan, 40m, 20, 15m. It works, and pretty good. I tuned it with a NanoVNA and the SWR is about 1:1 - 1:2 for all bands I use. But, I feel like theres more to tuning than just SWR. Is the perfect antenna going to be 50ohm+0j ? Is it the imaginary part that changes the SWR? How do you get a piece of copper wire to change its resistance to get to 50ohms if its not? How does all this fit together? If i mess with it enough am I ever going to get close to 50ohm+0j ? Should i even care, if it works pretty good as is?

DIY 40m Antenna tuning: RLC and SWR

I keep hearing the recommendation to make your SWR as low as possible and that would imply good tuning.

I'm a new HAM and made a centre-fed half wave fan, 40m, 20, 15m. It works, and pretty well. 

I tuned it with a NanoVNA and the SWR is about 1:1 - 1:2 for all bands I use. 

But I suspect there's more to tuning than just SWR.

  • Is the perfect antenna going to be (50+0j) Ω?
  • Is it the imaginary part that changes the SWR?
  • How do you get a piece of copper wire to change its resistance to get to 50 Ω if its not?
  • How does all this fit together?
  • If I mess with it enough, am I ever going to get close to (50+0j) Ω?
  • Should I even care, if it works pretty well as is?
Source Link
lornop
lornop
  • 31
  • 4

DIY 40m Antenna - RLC and SWR

Been searching for an answer for antenna tuning. I keep hearing to make your SWR as low as possible and thats good. Im a new HAM and made a Centre fed half wave fan, 40m, 20, 15m. It works, and pretty good. I tuned it with a NanoVNA and the SWR is about 1:1 - 1:2 for all bands I use. But, I feel like theres more to tuning than just SWR. Is the perfect antenna going to be 50ohm+0j ? Is it the imaginary part that changes the SWR? How do you get a piece of copper wire to change its resistance to get to 50ohms if its not? How does all this fit together? If i mess with it enough am I ever going to get close to 50ohm+0j ? Should i even care, if it works pretty good as is?