My complex antenna works well on 30m after modification!
I had added 2.5m of wire to either side along with 122 microhenries coils on both sides of 20m elements in my multi-band fan dipole antenna. As it had not resonated on the intended 80m band, I decided to increase length by 2m on either side, which is the maximum amount of twisted and folded back wire. First I changed length only on one side and tested the resonance pattern on NanoVNA. Now it is an off center fed dipole for that set of elements with additional loading coils. That is 5+4.5m on one side and 5+2.5m on the other side. Here is the NanoVNA SWR tracing from 1 to 11 MHz.
In this enlarged view, you can see that the SWR dip is at 10.2 MHz, just above the 30m amateur radio band. I could easily tune it with the auto-tuner in my FT-710 radio and have contacts with stations in Italy and Turkey today morning on 30m amateur radio band.
Next dip in SWR seen on NanoVNA was at 6.9 MHz, very near the 40m amateur radio band. That also I could tune well and check in to local morning nets with 5,9+ reports.
Another very narrow dip was seen just above the VU 80m band, at 3.8 MHz. It is well within the 80m amateur radio band in some regions. But the SWR was 3.382, above the tunable limit of my radio. Maybe, if I extend the other arm of the loaded coil elements and make the antenna center fed, it might resonate well on the 80m band. But I wish to defer it for some time and try working 30m for a few days and then try it. That is because currently very few stations are heard on 80m, while there are plenty on 30m. If I extend the other limb of the loaded coil dipole, I am sure to lose access to 30m amateur radio band.
SWR was 2.342 at 28 MHz, the 10m amateur radio band. It was tunable to 1:1 SWR with the auto-tuner in the radio.
SWR dip of 1.802 at 21.750 MHz permitted tuning and operation on 15m amateur radio band, which is just below that.
Narrow dip at 13.750 MHz with SWR 2.780 was not tunable on the 20m amateur radio band. So I am still cut-off from the 20m band which had the best SWR in the fan dipole prior to adding the loading coils and extension wire.