The 47.2" handwritten on the manual is 120 cm converted to 47.25" inches, so it did not represent the length to set for CB.
I'm also not sure about the measurements you gave us for your gamma. You note you used the setting for the New Vector @ 930 mm or 36.7". My measurement was 35.5" from the bottom of the gamma to the top edge of the dog bone connector I think. You will have to think about the gamma and try what you think best.
The New Vector 4000 is much shorter than your antenna and the radials are much longer, and I'm not sure that 81.5" is long enough. My radials are 91.25" long, but that might not be what your antenna should have. The New Vector radials are about 106" I think. I discuss a scheme on the radials that CTE touches on in this regard below.
I just realized why the manual I sent you has the dimension (cm90/35.5") from the spreaders up to the bottom of the hoop, because if you set that dimension correctly, it will give you the proper length for their radials. The top portion probably goes down inside the bottom portion just a bit before the set screw secures them together, both being inside to the radial support tip. You'll have to look closely at this idea and think about it if you don't understand my words here.
This antenna was pretty much plug and play, just like the New Vector and the New Top One, as far as the length of radiator and radials are concerned.
Like I said earlier, the top element is the only thing to move up or down to set the length you want, and according to Bob85 and others on this forum, they will tell you that you can tune the frequency you want, for any particular length within reason, just by adjusting the gamma dog bone space and the gamma rod length. This is not too different a procedure than the New Vector instructions shows, however the numbers may be different, due to different construction. So you will have to figure that out as well.
The gamma I used to take the images was from a CTE Vector, and the marks on it were left from the owner using that tar type coax seal tape. When removed it leaves a dark stain and that suggests where it was set. You might try those measurements and see it you get a better match.
Did you check to see if your feed point showed good?
How did you come to the overall length that you used originally? Did you go by some marks on the antenna? If so, and it worked for you before, then it should work now. But IMO, you must get the radials right first and I think they are way too short.
Do you see the radial bending a bit. They probably should be perfectly straight within reason and this is due to the construction idea they use. This is the reason they give you the dimension for the radial supports up to the bottom of the hoop, and before now I never understood why they would give you that seemingly unimportant dimension.
BTW, I have sold this antenna before and got several bad reports about the thing acting bad, but I always thought it was due to bad construction when installed, and now I'm sure of that.
Good luck and keep us posted...and thanks for helping me understand an issue that has alluded me for years. Most guys would have run away mad on being questioned, so thanks.
Marconi
