nanoVNA - Balun vs No Balun... any difference? Does the nanoVNA produce interference?
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- Опубликовано: 19 сен 2024
- Continuing on the last video posted... Is there any noticeable difference in the measurements using the nanoVNA when the balun on my 80m dipole is bypassed?
Discovery of potential interference being radiated on the 80m band from the nanoVNA while measuring antennas!
0:55 - nanoVNA saver software - using the software to sweep an antenna.
2:20 - Some troubleshooting is required. Haha!
3:14 - Finding the resonant frequency of the antenna using the software.
3:49 - The results of the measurement. No balun vs balun comparison...
4:50 - How to make higher resolution sweeps, more data points!
6:29 - Please feel free to fall asleep here. Boring rambling about finding a better way to locate the frequency of resonance automatically using nanoVNA software... please feel free to share in comments if you know how to do this, or if it's even possible in the software.
7:16 - Pulling up a previously saved sweep to examine it at a later date for station maintenance.
8:59 - nanoVNA creating interference on the band?
12:38 - Summary and a new question to investigate and answer!
13:34 - Logged a contact from Canada to Slovenia on 17 meters! 73 and see you next time!
VE6WGM (VE6WO)
Very informative video and you made a good point regarding the VNA causing continual interference. I didn't realise that. Great video, well presented, shame about the intro music noise. 😉
Haha! Yeah, I was waiting for the ribbing on that.. and here it is! Lol!
@@ve6wo Lol! Your videos are really good and now I skip the first 40 secs or so to get to the good stuff. Keep up the good work!
@@acestudioscouk-Ace-G0ACE sorry the intro is painful. Haha. This whole project is definitely a work in progress, and I’ll keep trying to learn and improve as I go. Thank you for your patience.
The balun keeps your coax shield at ground potential and keeps the coax from adding a spurious radiation sidelobe at a high launch angle. Mostly for the purists as you've measured nearly the same characteristic seen by the transmitter.
Interesting to know that the addition of a choke made little difference. I use chokes to reduce RF. Great video and Many thanks.
Ahhhh, but if I can see no difference using the nanoVNA, why would we need a balun? Next video.. ;-)
@@ve6wo Reduces common mode interference.
I can't remember exactly where I heard this. But someone mentioned that using a balun is not always needed. In the beginning of my ham ventures I used one once. Didn't ever use one after that as it did seem to do anything.
That might be something to experiment with.
Nice video. Gets me motivated to delve deeper in my Nano VNA.
If it wasn't doing anything, then it wasn't designed and built right !
Or perhaps there was another point to be made.. further investigation is needed to understand what’s going on here… which is what happens in a follow up video… 😉
Thanks, Gregg, nicely done! I have a Nano VNA I need to get smart on... look like I need to dive into some of your vids!
Common Mode Current Balun is preferred
Would also be nice to hear / see any difference with the balun switched in or out with a relay for the demo.
You'll get even better results on the screen if you swap out that imperfect antenna for a high quality dummy load.
I mean, it won't radiate anything, but the results on the screen will be good, and that's the main thing right? ;)