No one has verified that Solarcon has cut only the top of the top section, or did they cut 3" on each section? I'm guessing that just a 3" trim job off of one section would be enough to prevent getting an acceptable SWR on 11 meter.
Recon, consider this. The 5/8 wave vertical is not a resonant length antenna...thus we see Maco's V58 at a much shorter length than the Imax, SP500, etc. Among these later antennas, among others, we also see differences in lengths. IMO all these different lengths...
are likely due to the differences in the matching systems used. The notable differences here may also be that the Imax matching system provides for an abundance of bandwidth compared to the other 5/8 waves that show relatively shorter BW curves, etc.
Thus IMO, the very broad BW of the Imax should easily allow for a very low working match <2.00:1 SWR for 10, 11, 12 meter from 28 - 25 Mhz is 3 MHz, and maybe more. Based on my recollections...I seem to recall my Imax, without a GPK, the overall BW was closer to 5 MHz when using a long feed line. Maybe not as much at the antenna feed point.
Yeah you're right again. It's just a CB issue, so why should / would Solarcon consider making an antenna with four shorter sections to add up to 24' for CB when they can trim the existing antenna and keep customers who use the other frequencies / bands?
Solarcon could also make an Imax specifically for the 10 meter band, but making it 4 sections for CB would seem to me a big added investment, and maybe they were concerned that CB is not booming these days.
Making the Imax shorter by cutting the tip only...will not solve the issue for shipping as noted here either.
Note: Sirio chose to make their 5/8 wavelength Gain Mast into 4 sections instead of three...and maybe for several good reasons. Their antenna also has a very broad bandwidth. Ideas change over time as does the market place and consumers.
The ideas about the Gain Master and their wide BW has been pretty well discussed and understood of late. However, I don't think this antenna is generally discussed in the Ham community...as being somewhat mult-banded, like some Ham operators do regarding the Imax.
IMO the big difference between the Imax and the GM, is the GM does a great job of minimizing CMC's, and the Imax does not. Could the combination of the Imax and the feed line and mast radiating almost as well as the radiator...have implications for it being somewhat multi-banded? That possible use is likely of little interest to the CB community.
Below in the PDF file is an image taken from an Imax 2000 Manual and noted with a (*) for this point of interest about specification and changes.
Solarcon is telling us that construction variations are possible and also that advancements in their design can require changes in the dimensions. They tell us, they can do this without notice. Like it or not, the policy is in the fine print.
They also offer solutions for problems and advise owners to contact their dealer if not satisfied. They also have a product return procedure and policy. They either honor this or not, and in my experience the policy worked as stated and I hoped for.
Yesterday, I called an old CB buddy that I've heard on 10 meters many times, but I never took note of his call sign as I'm not a Ham. I haven't visited with him since 2002, but we did talk on the phone a bit. Two years ago DB (his CB handle) ask me if I had an Imax that he could buy, and I sold him a new one still in the box. He called me later and reported the Imax was working fine and had a better match than he expected at about 40' feet on his tower.
He also told me he recently had his 3rd stoke in a year and was still weak, so I didn't quiz him much. I did ask him my question however, if he ever checked and recorded the <2.00:1 SWR bandwidth in his log, and he said no. He also suggested the Imax, without a GPK, worked well lower in frequency, but he didn't remember the details.
He also told me he was in a group, I think on FaceBook, that discussed the multiband ideas for EFHW antennas and the Imax in particular. He said, that is why he was looking for an Imax. I wanted to try and pick his brain, but he was sick. Hopefully, I can follow up later.
I also remember years ago talking to someone, supposedly a tech guy at Solarcon. I had just learned some ideas about Common Mode Current here on the forum from Bob85, and he was claiming the A99 was probably the best candidate to demonstrate those bad effects. If these conversations were not too far back, prior to some dubious WWDX updates...where files were lost...
a forum Search might find something along these lines.
What I heard from this Solarcon expert was the sometimes CMC can be beneficial for how a particular antenna might perform even if other issues prevail. He said the A99 was such an example...using the coax shield to improve the net radiated signals in a constructive way. He said he could not elaborate further at the time. He did follow up and emailed me a White Paper Report explaining this idea in simple words. I wish I still had that paper. All of my testing over the years for the A99 are gone missing.
Somewhere I have heard or read that the Imax without the GPK will allow the antenna to perform multi band somewhat. I'm curious and sure there is someone out there that has worked an Imax and could confirm or deny this idea.
