I apologize for getting back on topic but does anyone know how much power this antenna should handle? 73, Joe, W8JH
The power handling is a function of the distance between the capacitor plates at the top. In addition, other factors come into play such as humidity, dust etc. However, it is safe to say 100 watts wouldn't be an issue, and would handle more.
Interesting video, thanks ERIC for the presentation and explanation. I will look for more info and I would like to try this loop in my qth. 73' Joe
It's funny that a thread goes 4 pages deep for a glorified dummy load on a band that is dead as a doorknob, but a good QRZ article like this is growing cobwebs. At least people are home-brewing though!
Yes, indeedy. I'm going to let the naysayers have their fun; STLs will remain one of the best kept secrets of the compact antenna world---and that's OK by me. 73, Jeff
The so-called ham antenna community isn't exactly nurturing. Who needs the abuse? Looks like VE3UK used a CNC machine to cut it....nice. If you had dictated that size and searched for solutions, you would have found a Minkowski fractal would be somewhat bigger (oh, 25+ inches) but cost about 80 cents, and five minutes of patience with a 3-nail jig. 50 ohms, 2+ Meg bandwidth, 2+ dBi. But hey....STL's look more like the plastic crystal radio/antennas we used as kids, so they must be cool....and we love living in the past :-( Same old antennas, (usually)derivative PRC-made tools to get there. Such is 'innovation' in ham radio in the modern era one supposes. It USED to be fun to work with our hands, and minds. Anyway, if you WANT an STL on 6m, this is certainly an elegant one from VE3UK.
IOW its a capacitor subject to voltage arcing and the problems of using an 'air' dielectric. Hey, why use a substrate dielectric when you can eake out such compromised power with air alone? Christmas....when you guys discover 'FR4' let me know.
If and when Bob implements a vacuum variable option for his finely-crafted loop we'll certainly let you know---we wouldn't want to let down the nurturing side of our "community" now, would we? Give Bob a break---he deserves better for coming up with something that will particularly appeal to the QRP, digital and SOTA enthusuasts---among others. As he stated earlier, he did this primarily as a learning experiment and one that would inspire hams to tinker and DIY antennas. Hope he sells plenty!
Well then be prepared for alleged 'antenna gurus' in ham circles saying things like 'STL's are like the copper bracelets of medical devices'. But I'm game: let's say there's this new tool of making STL's from CNC's.... sincerely now: where do you go with it? What additional experimentation does it enable? What else do you learn by this? What can you do that you couldn't do before? How does this, in the US, meet the mission of Part 97? Unlike the abuse I have sustained, I am not inveighing such an attitude. I am asserting that you always have to ask: 'what problem am I trying to solve'? A major point to consider is that thick loops are preferred when --very small-- loops are used as STL's, because this cuts down the ohmic loss. I doubt very much that at this diameter, on 6M, you need a thick loop such as this. It may look nice, but what RF purpose does it serve? For example, a 20M scaled version of this would be a whopping 63-65 inches. And I will let you figure out the thickness when it scales. 73 Chip W1YW
Too expensive. Don't need it. See I3VHF's solution for high power. VE3UK should make the loop smaller so that you can put it, flat, in a backpack.
No. They only interact with magnetic fields in the very near field in the same plane of polarization. The flip side of this is that they don't interact with noise sources in the near field of opposite polarization. This is the reason they are often claimed to"reject noise" or that they are "quieter". Tom, W8JI discussion. https://www.w8ji.com/magnetic_receiving_loops.htm https://www.w8ji.com/radiation_and_fields.htm