At last, I had a chance of testing my new loop antenna. The loop consists of a copper wire hooked to three chimneys positioned in an almost equilateral triangle configuration, the length of the wire is about 42-43 metres and about 7 metres above ground level.
I fed the antenna with approximately 7-8 metres of 450Ω twin line and terminated this feeding section with a 1:1 current balun. The unbalanced side of the balun is connected to approximately 2 metres of RG8 Mini coaxial cable and, through it, to an automatic matching unit and then my IC-7100.
Despite the not at all accurate configuration, the whole system appears to work reasonably well. The QRM is very low, aside from the noise generated by some cheap LED bulbs in the house. I am learning the hard way how much noise certain bulbs produce – if you like LED light and have an antenna just above the house, buy one first and test it for noise across the RF spectrum. However, bulbs apart, the antenna is very quiet on pretty much all bands when compared to other types of wire antennae.
I am not yet able to confidently tell how well it performs as I still have to compare it with something else. I am now looking at installing an OCF dipole nearby so that I can then switch from one to the other and see which one performs better. I tested it a bit these days with WSPR. With 5W TX power, the only place on the globe that I haven’t reached is South America. From Vladivostok to Cape Town, going through Australia, the US and New Zealand, I managed to collect reports but I have no idea of how many reports I could get, say with a magnetic loop. I know I don’t sound very enthusiastic about it, but this is pretty much what everyone with a wire in their backyard and 5W claims when they use WSPR. In the end, a side-by-side comparison with other antennae will tell me how good it is.
With this hobby you never get bored!