[Antennas] CushCraft R-7 problems

Sun Dec 27 18:42:12 EST 2015

The house has aluminum siding. The antenna sits up on the roof, maybe 
10ft above the siding and maybe 20ft away from it; the roof mounting 
spot is around 20ft above ground. I think the problem is with the 
antenna itself, not the installation context/environment. I had a 
SkyHawk beam, and the SWR never varied on that antenna, regardless of 
the wind/weather. So, the wide/wild fluctuations of the SWR when 
measuring it in a very slight breeze is suspicious of something mechanical.
...robert
On 12/27/2015 22:56, JK wrote:
> How far away from ur house? Have aluminum siding. Any towers nearby? Any
> vertical wires or metallic objects near the antenna?
>>> Check continuity w/ohmmeter?
>>> Jay...NE2Q
>>> On Sun, Dec 27, 2015 at 05:29 PM, Robert G Strickland wrote:
>>> Hi, Jay...
>>>> Brand new!
>>>> ...robert
>>>> On 12/27/2015 21:01, JK wrote:
>>> Is this a new and unused antenna??? Maybe a bad trap/coil
>>>>>>>>> Jay....NE2Q
>>>>>>>>> On Sun, Dec 27, 2015 at 01:29 PM, Robert G Strickland wrote:
>>>>>>> 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
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>>>>>>>>>>> --
>> Robert G Strickland, PhD ABPH - KE2WY
>> rcrgs at verizon.net.usa
>> Syracuse, New York, USA
>>>
-- 
Robert G Strickland, PhD ABPH - KE2WY
rcrgs at verizon.net.usa
Syracuse, New York, USA