i thought about a bicycle rim :D but i kinda wana keep this a mobile setup…

i have been thinking about inflatable loops recently, sadly i was only able to find a singular example of those (some guy slapping some aluminum foil onto a inflatable swimming tire and it didnt work that well).

My idea would be to take some copper braid sleeve (5cm diameter) and put a inner bike tire thru that. As far as i can tell nobody has tryed that before…and i keep wondering, if i add a small electric pump to the setup i could maybe tune the loop by inflating and deflating it while using a non variable capacitor.

Yeah i am planing to build a remote controlled coax capacitor eventually (probably something like this: https://antennenbau.dxfreun.de/krampfader/image/Balkon-Loop/Abstimmbereich_MagLoop.jpg ) but right now i am still waiting for some parts to make that happen.

The additional high voltage durability of the serial coax capacitor is nice, (should be now 5kv, since a single RG58 has 2.5kv) but i doubt i gona need that with my 4W Tx ^^

i might be wrong here but i think a dummy load is different from a terminator, they both 50 ohm, but a terminator is more like a connector cap, while a dummy load is designed to dissipate heat and can often take many watts of power over extended time without starting glow

Ah yeah sad, southern germany is a bit far away (besides maybe during high solar activity but even they the skips may fly just right over). Thx for doing some calculations, on the safety distance aspect of it, i kinda assume the psychological effect (knowing that u in the RF near field) is probably bigger an the real effect of 4W of RF heating…and i probably just hallucinated the slight metallic taste in my mouth after 1min of keying down while tx testing (my brain do be like that sometimes).

My repositioning the primary loop i managed to get the SWR down to 1.5 :D

I just hoped i aint cooking my insides when transmitting while sitting next to the loop antenna, a online calculator said at 4W i should keep at least 13cm distance from the antenna, but that was for a dipole not a loop…i need a longer feedline to get some distance…

I currently at berlin/brandenburg area, i kinda dont think i will be able to make long distance connection till i upgrade my radio to one that supports SSB tx with 12W (AE5900 eventually i hope). Long term i hope to manage to get a setup that allows me to join the europe wide JS8CALL network on 27.245Mhz. JS8CALL supports message forwarding over other nodes, a bit like meshtastic, i heared of people who managed to comunicate to australia via JS8CALL using multiple forwarding nodes, it is very slow tho due to using the same mode as FT8

I can feel this meme resonating with me

I love the word Mantelwellensperre, peak german language :D

I build a Air-Core choke from a part of feed line right below the antenna now, and got some slight improvements.

I will try to improve the feeding loop position to see if it gets the swr down a bit more. By now i am already quite happy with the antenna, during a test i managed to make a ~15km Thor8 connection while the antenna was still inside the house (with 4W AM Tx and the receiver in SSB/USB).

This is my capacitor (RG58):

I dont have ferrite beads right now sadly, but i will try to make a Air-Core choke from parts of the coax feed line, maybe that helps.

If i would use a balun between feed line and antenna, i need a 1:1 balun i assume?

I will try to find the frequency where the impedance gets real. Also gona try to maybe build a variable capacitor from 2 metal pipes going into each other depth regulated by a screw, but i mostly wana use this antenna on a single frequency so i hope i dont need much adjustment.

Here is the measurement with smith chart:

There is 2m of BNC RG58 coax between the antenna and the NanoVNA. I calibrated the NanoVNA without the coax line because i was under the impression the line to the antenna is considered part of the radiating system and hence should not be calibrated out. But here is the reading with the coax line to the antenna calibrated out:

Thank you for your answer!

I think i found the root of my problem, the scale settings on the NanoVNA where wrong, to a point where the super slim SWR dip of the Loop was just not drawn on the graph for lack of data points at this point. I changed the scale and was able to see the dip, then tune the coax stub to the frequency i wanted. Now it claims to have a SWR of 3.8 near the frequency i want to use:

But i am still a bit confused, the yellow number left of the SWR reading, i assume that is the scale? or does it mean a SWR of 6.125:3.8?

Edit: Just tested reception, and its way better than before, also Tx works a lot better now, i would say almost on par with my Dipole just with more directionality

thank you for making 8 pannel content

thank you for making 4 panel content!

apparently there is still a 2m FM gateway online in belarus somehow https://freeradionetwork.eu/gateway_repeaters.php i would not date to connect to listen in tho

that is basically the fear that keeps me confined to CB radio rn

German empire Country ball eyes, i believe that’s a hidden message…possible metaphor for whats happening to the USA

it was a typo i meant IME

Thank you for making IME content!

Thank you for making Foss Upraising content!

Thank you for resonating with my content!

Thank your for engaging with europe is lame content!