开云体育

I posted both sweeps to my blog. A link to it is in another post I made to this thread. I don't know if it will be above or below this post because I don't know how groups.io orders these replies. :)

I don't think there would be a problem with hosting the PDF somewhere with proper source credit. I grabbed it off the net some years ago. The original web article is no longer up and the Internet

Attached are some plots for a antenna with nominal impedance 52 ohms at resonance of 10MHz, with zero and 1 dB loss in the feedline. I chose the 52 ohms so that it wasn't a perfect match to 50 ohms so

Great! Thanks, Roger. I added that to my reference section. de KK7XO

Here you go >>> http://pabut.org/JPOLE.HTM Roger

Here is a link to my blog post: https://www.multiquadratic.com/wordpress/index.php/2021/09/15/designing-a-twinlead-j-pole-antenna-using-simsmith-and-the-nanovna By the way, that J-Pole article Jim

The definitive article on the Jpole was written by N3GO some years ago. From a J to a Zepp The truth and its consequences Gary E. O'Neil, Raleigh, N.C. (N3GO) 73 -Jim NU0C "KENT BRITAIN"

I'm using a choke on the antenna feed. It may not be enough inductance, but it's better than nothing. Once I finish my blog post I'll put up a link in this thread. By the way, Roger, I'm using your

Thanks again! I missed that in your post... Thanks again!! 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical Specialist, RFI ARRL Asst. Director, NW Division,

Sure, think about how putting, say, a 3dB pad would change the 2:1 bandwidth - it would make it wider, because it pushes the entire trace down 6dB. You can see that on the plot I just posted - look at

On Sun, Sep 19, 2021 at 09:15 AM, Jim Lux wrote kk7xo is measuring a J-Pole. Those antennas are famous for radiating on the outside surface of the shield and need good RF chokes. Something to consider

Hi Jim, THANK YOU! I also have a Rig Expert AA-600. If I sweep at the shack, I get a 2:1 bandwidth that is far wider, than if I sweep at the antenna feedpoint. Why does the nano not show this same

Terry Turner, W5ETG, now a silent Key, was the first to develop the twinlead J-Pole back in the 1960's.? ?That puppy has certainly traveled far!? ?The hard part today is finding Twinlead! hihi

Here's an example of a 6BTV with 100 ft of RG-8X. Blue trace is cal at the NanoVNA Orange trace is cal at the end of the Coax. You can pretty clearly see the loss of the coax increasing with

If you sweep with your calibration plane at the antenna, and at the VNA, I would like to see those results... 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical

SO-239 are not so bad at VHF, and in theory the affect generated by the connectors, in general, is equal across a broad frequency range. If you are within that range, then the connector type is not an

I think |S11| = -20dB is more like 1:1.22 VSWR 1:1.1 is 26 dB 1:1.5 is 14 dB 1:2 is 10 dB https://www.amphenolrf.com/vswr-conversion-chart

Thanks. The reason I'm doing this is because I made a blog post about how to design a 2-meter twinlead J-Pole using SimSmith and the NanoVNA. One of my readers asked me to post a final sweep of the

Yes, you will lose a bit of dynamic range. However, consider the "raw" dynamic range of the NANOs. At 2-meters, you have more than enough dynamic range in the instrument to throw away a bit. Actually,

You'll lose a little bit of dynamic range, but, really, how much do you need.? If your antenna has a |S11| of -20dB or -30dB, then the fact that the dynamic range is now 50dB instead of 60dB isn't