Timeline for answer to How do I design a dual band LPDA antenna? by tomnexus
Current License: CC BY-SA 4.0
Post Revisions
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jul 24, 2019 at 5:51 | vote | accept | brandon3055 | ||
| Jul 24, 2019 at 5:51 | comment | added | brandon3055 | Sorry i did not get back to you i have not had time to mess with this. When i get time i will take another crack at designing a gaped antenna but considering i would only be removing 20% of the frequency range i think my best bet would be to just create a simple antenna that covers the entire range from about 650 to 3000. That way i can just use an existing calculator like this one hamwaves.com/lpda/en/index.html and be reasonably sure it will work. Thank you for all of your help! | |
| Jul 20, 2019 at 20:53 | comment | added | tomnexus | I think I did exactly that - I generated the lpda from the back, wire by wire, hooking them up with TLs. You could take the header and footer off a known good simulation so you only have to figure out the GW, TL and (googles it) EX cards, and use the GUI tools to make your plots. nec2.org has it all. Congratulations on getting so deep into the simulation already. Remember NEC is easily offended and will give bad results if you break the rules, so keep the structure simple and don't try to model small details. | |
| Jul 20, 2019 at 11:22 | comment | added | brandon3055 | Im guessing my best bet is to figure out the nec format (it does not look to complicated) and write a script that will allow me to remove elements without breaking the model. But before i do that i am just wondering if you know of a better way to modify the nec file? | |
| Jul 20, 2019 at 11:19 | comment | added | brandon3055 | Thank you this is incredibly helpful! It seems so obvious now that you have mentioned it. What i am looking for is just a LPDA with a section removed. I have just spent some time figuring out the simulation software. I have figured out how to generate a custom nec file for my required frequency range using LPCAD and i found this application that lets me test the nec model and check its performance qsl.net/4nec2 ss.brandon3055.com/5aa12 Now the only thing i have not figured out is how to remove a section. | |
| Jul 19, 2019 at 13:26 | history | answered | tomnexus | CC BY-SA 4.0 |