Spotted for First Time on 12m on RBN with 80m Zig-Zag Off Center Fed Linear Loaded Inverted V Dipole

Folded back 76 cm from the Western side of my 80m antenna under construction, which is a zig-zag off center fed linear loaded inverted V dipole with three layers for a half wave. Approximate sketch of the layout of the antenna is shown. Initial dimensions after the trial of loaded coil antenna was approximately 14m and total of 27m of wire was added in an asymmetric fashion, including short folds for mounting, in the hope of increasing the feedpoint impedance of the linear loaded dipole with three layers which is supposed to have only one third the impedance of a half wave dipole antenna of same dimension. Total wire on the air would have been slightly above half wave length for 80m. That is why the new test with reduction of 76 cm by folding back.

SWR on 80m was still very high, quite beyond the tunable range of the built-in antenna tuner of FT-710 with no hopes of operation on 80m.

SWR was around 3 across the 30m band as before, most likely in the tunable range of the radio, though I did not check this time.

Of more interest to me was that it was similar on 12m band as well and was tunable with the automatic antenna tuner of FT-710 radio.

Tried calling CQ on CW at the lower end of 12m band, just for a trial. You can see that though the tuned SWR shown in the SWR meter of the radio is almost 1, the SWR in the feedline is elevated, as can be seen in the external SWR meter. Forward power can be seen as full and reflected power about about 30%. I have read that the reflected power will be sent back to the antenna in the next cycle, though part of it will be again reflected back, causing resistive loss in the feedline. I have only 15m of RG213 cable and feedline losses may not be that high, or so I presume.

Anyway, significant amount of power has been radiated, as you can see from the spotting on the Reverse Beacon Network at a distance of 2568 miles by VR2FUN-77, with signal to noise ratio of 7 dB. That is not bad for a very suboptimal antenna with apex at just 7m from the ground and ends about 2m from the ground. In fact this is the first ever time that I have been spotted on RBN on 12m. So that is an all time new or ATNO for me as the ‘Genetic Antenna‘ continues to evolve! May be 7th harmonic resonance of 80m antenna on 12m!