Hi Clint, I believe there is a feature that lets you save both antenna's S/N ratios over time in SDRuno. It writes a CSV file of values, which you could later graph out and compare, and/or simply average the numeric values to see which antenna is truly the "S/N champion". I'd guess that a 10-minute CSV file of both antennas' performance this way could indicate if there is a clear-cut winner or not. 73, Guy
Hi there Guy, thanks, yes there is a feature that allows you to do just that and I think it is a CSV file that can be imported into Excel. I'll have a go at that tonight if I get time. Keep safe my friend. 73s, Clint
The Bonito needs to be up in the clear like the wellbrook. I can imagine that fence is having some effect on the Bonito. I got the 10 meter wire version mega loop. Up in a tree works great.
I Have the smaller loop and 5m one for megaloop fx and dependeing on amplification settings and filters, they perform very differently. I agree that they should be similarly positioned. I am not sure also if placing them within each others nearfield will cause issues that make true comparison problematic.
I think if you take another look at the video there are two Wellbrook loops - the one mounted on a tripod is not part of this comparison test. The other is mounted on a fence in an identical manner to the MegaLoopFX. As for the fence conducting EM radiation or magnetic field/electric fields separately, I think not and even if partially grounded when wet, again there is no electrical contact path between the loops and the fence itself. Thus, any effects would rely on either inductive or non-inductive coupling. Having spent over 30 years working in the field of electromagnetism and having used both loops for several years, I think I can allay your concerns. 73s, Clint
Again, you should actually watch the video - there are two Wellbrook loops and one is positioned in an identical manner to the MegaLoopFX! Your point about relative positioning in near field is actually valid but easily tested by monitoring both signals simultaneously and shutting one of the antennas down. You won't be surprised to learn I've already done that and there is no observable effect on the RSP DUO spectrum. 73s, Clint
@@OxfordShortwaveLog Thank you for kindly requesting to watch your video more accurately. What in your opinion explains best the differences between the two antennas which your presented in this video?
@@OxfordShortwaveLog You're correct, apologies, I remember seeing the bubble wrap thinking that was off the loop on the tripod! DOH ! haha. I'll pay more attention next time Clint. :-) I think the extra 5 meters of wire I have on my Megaloop makes a notable difference. By the way, time to spray that Robin-Run-The-Hedge, God awful weed spreads like Wild Fire :-)
Hi! Do you remember by any chance, what was the gain setting on Bonito? I use the highest with 90 cm aluminum tube loop. I also wonder if changing triangle loop to a circle would improve the signal?
Hi I can't remember! You won't get any tangible change in performance by using a loop rather than a triangle - it's the electrical length that matters. 73
Clint. Just stumbled on your video. Many thanks and very interesting ! Can I please ask a question? With the loop antennas that use Coax cable as the actual loop itself, is it just the ACTUAL BRAID that receives the signal? In that case it would mean that the inner wire in effect is doing nothing and perhaps should not even be connected? . The braid would actually shield the inner conductor and thus it would actually not actually do anything ?? In case the small bore copper pipe is used, clearly, as there is no "inner", I wonder if the copper itself goes to the center connector or the outer ? Also, getting the the 8mm? copper pipe properly soldered to the actual inner of a BNC might pose some slight problems, but I am sure that those can be overcome. in fact, can the outer and inner of say a BNC plug be in fact shorted together and thus leaving BOTH the outer braid and the inner strands as ONE ? I can't see that working as in effect the input to the amplifier would see a dead short on it's input ? Also, I am right in thinking that the bigger the loop diameter/circumference the better the received signal strength will be ?? Please forgive my ignorance here. I have never explored loop antennas and since I will shortly take delivery of a KIWISDR I want to give folks that will connect the best possible signal. Many thanks Clint for having taken the time and effort to make the video, it is very much appreciated ! Albert EI7II.
Hi Albert, I'm not sure - but all I can say with any certainty is that you only need one conductor for the loop. The inner core of a coaxial cable would be a bad idea for obvious reasons. 73
@@OxfordShortwaveLog Clint... Yes, that of course makes imminent sense. I am waiting for wellbrook pre-amp before i construct the loop itself. BUT... would 10mm coax be as good as say an 8mm pure copper small bore waterpipe loop.? i am still in the position to decide as i have only the wellbrook preamp ordered sofar would very much appreciate yr thoughts ? Albert
@@OxfordShortwaveLog Clint. Many tks ! I will for now hook my KIWISDR up to my endfed 80-10 meter antenna... while Andi at wellbrook builds my Amp. Loop antennas are a closed book to me and it promises to be an interesting new area to explore. The KIWISDR manual is sooo detailed... I hope my olde wornout brain can hack it I will make the loop 2 meter in diameter, that should be me 6.28m of wire in the air. Time will tell Clint... and again thank you for your very useful videos. Albert
Interesting video, as usual. I would very much enjoy a comparison video of the Bonitos Megaloop FX and the Megactive MA305FT. I'm in the market for something "travel friendly" and well performing at the same time. If such a video is not on the cards, would you offer your opinion as to which of the two you would choose. Tnx!
Both run on USB 5V power which is perfect for portability. The antenna on the MA305FT is small and the MegaLoopFX loop is a cable so again perfect for travelling. Ultimately, the loop will always perform much better in electrically noisy environments and because you can't guarantee a quiet environment when you travel, it must be the MegaLoopFX (which is the antenna of choice for me when I travel). Hope that helps. Keep safe and 73s, Clint
Many tnx for your opinion. One more thing: is the galvanic isolator worth the price when used with the Megaloop? I didn't notice that you used one in this comparison with the Wellbrook where its performance appeared "mega".
Definitely it's worth the price when used with a mag loop. Depending on the level of local QRM you can expect the noise floor to reduce from 5 to 10 dBs. 73s
Hi Clint, turning the loop on the horizontal plane makes it omnidirectional.... maybe you should try that between those two and let us know. Keep safe 73!
@@OxfordShortwaveLog Thank You. My EFHW is aimed due North from my QTH (Atlanta, Ga.) I can reach Europe ( SSB 8 watts) but only sporadically. I'm thinking a more direct direct direction might yield better results. For right now, can only.orient my antenna this way due to lack of space behind my apartment.
Whenever an antenna needs a signal amplifier, such as a wellbrook, you're worsening SNR. Granted you can see higher signals on the S-meter with one, but they add more noise gain than signal gain, resulting in a worsened SNR.
You've missed a very important aspect of these antennas though - they're magnetic loops which means they reject the electric field component of a radio signal and they're directional which means you can null noise. 73s,
