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
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