[Antennas] CushCraft R-7 problems

Sun Dec 27 13:55:43 EST 2015

Hi Bob, 
have had number of R7...have some spare parts as 
well. 
For your case i would start google looking for repairs on traps 
of R7..faintly remember guy in Ireland, UK and Canada with suggestions 
how to... 
Secondly, check the resonant frequencies of the traps in question... 
when they do not agree with settings...as recomended by authors of 
articles of how to R7...repairs... 
Thirdly i will check in my laptop, what i have of R7 and send it to you... 
Kr and Happy new year, 
Nermin S58DX 
----- Izvorno sporočilo -----
Od: "Robert G Strickland" <rcrgs at verizon.net> 
Za: antennas at mailman.qth.net 
Poslano: nedelja, 27. december 2015 19:29:31 
Zadeva: [Antennas] CushCraft R-7 problems 
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 
______________________________________________________________ 
Antennas mailing list 
Home: http://mailman.qth.net/mailman/listinfo/antennas 
Help: http://mailman.qth.net/mmfaq.htm 
Post: mailto:Antennas at mailman.qth.net 
This list hosted by: http://www.qsl.net 
Please help support this email list: http://www.qsl.net/donate.html