-----Original Message-----
From: Tim Billings [SMTP:billings@nbnet.nb.ca]
Sent: June 7, 1998 1:38 PM
To: 'antennas@qth.net'
Subject: FW: R7000 VSWR Problems
-----Original Message-----
From: Tim Billings [SMTP:billings@nbnet.nb.ca]
Sent: June 3, 1998 8:24 PM
To: 'techsup@cushcraft.com'
Subject: R7000 VSWR Problems
HI.....I am an owner of a R7000 Vertical and I have been having problems in
trying to
lower the SWR on this antenna. The 10M, 15M and 17M band VSWR is fine...But I
have been unable to
lower the VSWR on 20M and 40M.
I have tried the following...
* Tested antenna at both feedpoint and at transmitter with no noticeable change
in VSWR
* Changed out coax feedline in an attempt to find problem in coax.
* Tested VSWR with 3 meters (Autek, radio, tuner)
* Relocated antenna
* Varied height above ground.
* Adjusted the lengths of the antenna sections in question.
* Checked the VSWR readings with another MN7000.... No change
* Cleaned all contacts and joints
All the above resulted in no changes in the high (6 to 9) VSWR.
HOWEVER.... I did disassemble the top two traps and cleaned the contact points.
When I reassembled
the traps and reinstalled the antenna with the dimensions as per the manual...
the VSWR was low...1.2 to 2
on the two bands in question..BUT..as power (80 to 100 watts) was applied the
VSWR climbed again to
6 to 9 on the 20M and 40M bands.
I am looking for solutions to correct the problem....Can you help ???
Thanks
73 de Tim VE9XA
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