开云体育

It's a bit late now for this reply, but here goes - Do it with both cables, and compare the results. Then you could share the results, too! I think it would be an interesting comparison. -- Doug,

The article by N3GO states "I ran a quick ELNEC [3] simulation of an end-fed vertical dipole to assess what feedpoint impedance it predicted. I varied the wire size and height above ground to observe

The ZIP file also contains the HTML article and the figures that go along with it. Open JPOLE.HTM with your browser and you will see the article with the referenced figures. 73 -Jim NU0C "Roger Need

That appears to be just a link to a zip file containing the calculation programs. No article there from what I can see. Roger

I found a link to the full content of the article: http://www.knightlites.org/n3go_workshop/index.htm N3GO renewed his license in 2019 so presumably he is still around. 73 -Jim NU0C "Roger Need via

That's pretty much what I am seeing, although my feedline loss is 1.4 dB, giving a total of 2.8 dB up and backj.

No kidding, it is the core of the famous terminated folded dipole, especially the ones made of stainless steel cables.? If you're an embassy, or state operator, and you've got that 10 mW in to 10kW

Again, thanks for sharing! 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical Specialist, RFI ARRL Asst. Director, NW Division, Technical Resources

Jim reminds me that loss matching and loss broadbanding are both accepted approaches in RF design. Of course the antenna is the worst place to introduce losses in the system, but I've seen it used to

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