[Antennas] CushCraft R-7 problems

Sun Dec 27 13:29:31 EST 2015

I have put up a CC R7 and can't get it to "work." CC has replaced the 
match box. Twice, I have taken it down, cleaned all connecting surfaces 
and put it back up. I have a lot of mechanical experience, and I'm 
generally satisfied that I assembled it correctly. Using an MFJ256B at 
the antenna, there is no resonant frequency dip on 30m, 17m, 15m and 
12m; on these bands the SWR is generally flat in the 2.5 to 7.5 range. 
On 40m there is a distinct dip at 7.05 MHz with SWR 2.5:1. On 20m there 
is a distinct dip at 13.850 MHz with SWR 2.5:1. On 10m there is a dip at 
27.500 MHz with SWR 2.3:1 . Also, when taking these readings there was a 
slight breeze and the SWR measurements were extremely unstable even 
though the vertical is guyed just below the traps. Aside from the usual 
comments about verticals and CC in particular, these results seem way 
out of line to me. A local ham has one, and using the 256B shows results 
that generally agree with those in the back of the assembly 
instructions. Any suggestions much appreciated. Happy New Year to all.
...robert
-- 
Robert G Strickland, PhD ABPH - KE2WY
rcrgs at verizon.net.usa
Syracuse, New York, USA