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Re: [TowerTalk] Perplexing Antenna Problem

To: <towertalk@contesting.com>
Subject: Re: [TowerTalk] Perplexing Antenna Problem
From: <kk9a@arrl.net>
Date: Sat, 28 Aug 2004 23:58:44 -0000
List-post: <mailto:towertalk@contesting.com>
The problem appears to be in the antenna.  Are the received signals strong
and does it appear to have a proper beam pattern when you rotate it?

John
(callsign) KK9A

----- Original Message -----
From: "Bernard(wtrone)" <wtrone@comcast.net>
To: <towertalk@contesting.com>
Sent: Saturday, August 28, 2004 19:40
Subject: [TowerTalk] Perplexing Antenna Problem


    I posted the following message on the Yahoo SteppIR board and thought
that I might also get some ideas on this board.


 I have an interesting problem for all of you antenna experts out there.  If
you have been reading this thread (Yahoo SteppIR board), you know that I
have been having problems with my new SteppIR 3 element beam.  I was able to
borrow a MFJ-259B this morning and made a relatively extensive set of
measurement, which taken as a whole, just do not make sense.

        In summary (2 measurements on 20, 1 on 17, 2 on 15, 1 on 12 and 2 on
10M for each series of readings):

            1. Set of measurements using the MFJ with a 20" length of coax
to the SteppIR.  Measured from 20-10M SWRs of from 1.5:1 to 1:1 (also have
the R and X measurements but won't go into those just yet).

            2. Set of measurements using the MFJ in the shack using the full
length of cable to the SteppIR.  Measured from 20-10M SWRs of from 1.4:1 to
1:1.

            3. Using MFJ to measure Coax Loss from 20-10M showed 1.3 to 1.6
dB.  Probably about 135 ft of cable.

            4. Put the cable in the shack directly on the antenna connector
of a Daiwa NS-660PA SWR and Power Meter, and the SWR is 5:1 from 20-10M.
The reading on the TenTec Orion is high VSWR.  Take the PL-259 off the
SteppIR and put it on a 50 ohm dummy load and the SWR is a flat 1:1 across
20-10M both on the Daiwa and Orion.

            5. Tried varying the "tune" power of the Orion from about 1 watt
to 50 watts.  No difference.

            6. Tried taking the Daiwa out of the circuit.  No difference.
Orion still reads high VSWR.

            7. Swapped out a complete set of coax cables to insure nothing
was common.  No difference.

    Anyone out there in radio land have any ideas?  I am going to talk to
Jim on Monday, but this is really a STRANGE set of data.  I am a bit
perplexed with what I am seeing!

                73,



                Bernard, WA4OEJ
_______________________________________________

See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.

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_______________________________________________

See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless Weather 
Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any questions 
and ask for Sherman, W2FLA.

_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

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