That's easy. Four full 1/4 wave radials are better then eight radials that are less then five feet long. Eight full 1/4 wave radials makes no practical difference over the first four.
Hello Shockwave. I may agree with your first comment, simply because of some modeling work that W5ALT did. Admittedly he did not address adding radials, but he does model for varying lengths of radials for the 5/8 and his report supports the idea that longer radials tend to be a little better up to a point about a 1/2 wl. He also notes that radials any longer will change things dramatically. I tend to agree with his conclusions, assuming his modeling is close to correct.
See:
W5ALT Antennas
Bob and I discussed this and he suggested that because the report does not indicate if the feed line and mast are included in his modeling, the report is useless. So, I'm not sure about the results, I don't know what he did either. I could be convinced of the errors of my ways on this issue however, if you have a bases of thought or testing even theory, and not just the claim.
Not sure at all about your second comment either. I haven't specifically compared adding radials to my 5/8 wave yet. However, when I did with my 1/4 wave, I saw a remarkable difference in performance using both a field strength meter and taking real world signals on-air back in 2006. That was pretty convincing for me, I had never seen such a dramatic response. I have my notes, and I will see if I can duplicate that effort to be sure. Then I will have something else to show, even if I have to disclaim my previous work.
I've had two episodes where I saw some indications that my I-10K and my .64 Wolf don't work well unless they have the full radial setup. A radial feel out of the Wolf and it noticeably affected the SWR. I checked my I-10K last summer to see if I could remove just part of the radials and I removed the tips, but no-way-no. The match was bad, but again I did nothing more---like try to retune. So both experiences were inconclusive for me to decide on shorter of no radials. The third deal is that my Imax works fine without radials at all, but in that case I suspect it is the matching scheme that allows it to still show a good match and work pretty good to boot. That just doesn't happen on the 5/8 or .64 I note above.
If your right Shockwave, four is just as good as eight, then I think it is probably because there is too little current flowing in the area of the radials (not a bad thing), to make a difference. IMO this is for sure the case if we compare my idea to the radials positioned in the maximum current area of a 1/4 wl setup.
