Eddie what have you used in terms of a full 22' 4" tall Metal 5/8 GP?I have never owned a SP500, but have several HyGain CLR2's which appear to be very similar in design, material, and construction to the SP500. The problems I see with my old HG's is their use of insulators. The base and top insulators came from antennas that were installed for years, and they all had cracks in them.
The newer 5/8 waves like the Shockwave and I-10K both use raised radiators and this puts a lot more stress on their insulators. These two antennas are heavy and that too needs to be considered if mounted above a horizontal beam.
Years ago I mounted a Starduster 7'> feet above my 4 element horizontal yagi. The SD'r radials hung down within a foot of the beam. I did not notice any SWR ill-effects with either antenna. However, these radials were pretty much vertical, so maybe that explains why I noticed little to no changes compared to both antennas standing alone in the same spot 27' feet high on a large roof-deck attached to my house. This was before analyzers, but on this deck I could tune and check my match at the feed point.
I've done two Eznec models. A 2 element horizontal yagi with a Super Penatrator 500 and horizontal radials above the beam. One model is set with the GP 4.5' feet above the yagi and the other GP is 9' feet above the yagi.
I also made two comparison models for both the GP and the beam standing alone, on the same mast, and at the same heights and I see very little difference compared to the SP500 above the yagi at either height 4.5' feet or 9' feet. The patterns do show a bit of difference, but they are close enough for government work.
Below are the overlays for comparisons and you can see there is not much difference.
Yup. Cheap coax is the trap for new players. You know what I'm talking about. They find out is is junk in a couple of years when the UV radiation breaks down the outer sheath and gets water intrusion; thereby ruining it with internal corrosion. As you mentioned, the cheap stuff just has too much loss compared to the better stuff as well. As we know, it is better to buy the good stuff and let it ride for 10-15-20 years and pay what it is worth at the git go . . .If changing his coax was responsible for 1 s-unit or 6db he would have had to have a long run of crappy coax before.
Naw, 6dB barely holds true for some Collins boat anchors.If changing his coax was responsible for 1 s-unit or 6db he would have had to have a long run of crappy coax before.
Yup. Cheap coax is the trap for new players. You know what I'm talking about. They find out is is junk in a couple of years when the UV radiation breaks down the outer sheath and gets water intrusion; thereby ruining it with internal corrosion. As you mentioned, the cheap stuff just has too much loss compared to the better stuff as well. As we know, it is better to buy the good stuff and let it ride for 10-15-20 years and pay what it is worth at the git go . . .
Robb you're right, but guys don't forget that water can get into your feed line from the inside as well as from the outside. The feed point itself needs to be protected from water....and gets water intrusion; thereby ruining it with internal corrosion.
Eddie what have you used in terms of a full 22' 4" tall Metal 5/8 GP?
Well the I-10k certainly qualifies.
Were you able to notice the difference in performance between it and the Wolf .64?
I added an S-unit to my signal using the I-1OK at about 90 miles by losing the top hat & extending it to a full .64, then retuning the match to X=0
What's the top hat on the I-10K, 12"L x 1"w? It's been years. Where does the I-10K zero up, about ch 22?I'm not sure I've ever compared my I-10K side by side with my Wolf .64. but according to some separate free standing signal reports I have on file...these two were pretty close. The Wolf showing a slight advantage, but I'm not sure about how the heights compared at the time of testing these free standing antennas.
On the other hand my Eznec models show the I-10K with a nice gain advantage. This said the Wolf is a more complicated model with the coils on the radiator...plus I've not worked on it since early in 2013, and back then this Wolf model was my first attempt at this antenna. I was disappointed at the results and never worked on it again.
Radials to tip, not including the top hat.
Wolf - 267.5" has two inductive coils on the radiator.
I-10K - 255.83"
Measured from top of insulator at base of mount to tip, not including the top hat.
CLR2 - 238" per specs in the manual.
What's the top hat on the I-10K, 12"L x 1"w? It's been years. Where does the I-10K zero up, about ch 22?