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I purchased a curious "QRP" loop antenna from AliExpress (I say QRP in quotes because the item is rated at 20 watts max and QRP is 5 watts), then assemble it, test it out, and then open up the control box and balun and find out what is inside these.
The loop part itself appears to be a piece of almost rigid extremely low loss coaxial cable, which holds itself in a loop shape when connected to the matching control box which uses two capacitors and a switch to increase and decrease capacitance, and how this works is revealed when I open up the matching unit.
I tried it on WSPR a couple of times, the second attempt the loop was near my living room window and the results were better, however it is useless inside the flat because of the electronic noise being generated inside the building, some of which may not be originating from my flat.
For the CB guys this doesn't work there without modification to change the capacitance and possibly a different size loop.
I have so far managed to get it to tune on 40 and 20 metres, though if I want to properly use it I will need to get out and buy a leisure battery to run the FT991A out in the wilds away from electrical noise
#amateurradio #hamradio #antenna #antennas
Chapters:
0:00 introduction and unboxing
6:57 Assembly
9:47 Tripod mounting
12:15 Checking resonance and tuning
17:29 Connected to the FT-991A and transmitting WSPR (1st attempt)
33:20 Inside the tuning box and balun box
41:40 Loop positioned near opened window and second attempts with WSPR
46:05 Conclusion