hello tom, the analyzer is almost useless on 160 and 80m
antennas. the reason is because you have so much broadcast signals
coming down the feed line that the analyzer is all messed up. in
areas where folks don't have the broadcast crap the analyzer does the
fine job. so go by the swr bridge and ignore the analyzer. even a
swr bridge is influenced by the length of the feed line, you could
have a 1:1 some where along the coax where the swr is really much
higher. the only way to use an swr bridge is through a electrical
half wave to the antenna or with the swr bridge at the feed
point. you can also use multiple electridal half waves between the
swr bridge and the ant. take care, c u 73 mike
At 05:28 PM 11/11/2011, you wrote:
>Hi, folks.
>
>Well, I have managed to get hold of an MFJ 259B antenna analyzer to help try
>to figure out what is going on with my 80 meter and 160 meter sloper
>antennas that we put up a few weeks ago.
>
>However, when taking some preliminary readings with the analyzer tonight,
>and comparing them against what my TW1 watt meter and the SWR meter on the
>TS590 say, I am getting very confusing results.
>
>Let me give a few examples:
>
>On 80 meters, my sloper has an SWR of about 5 to 1 on the top and bottom of
>80 meters, with a dip of 1.0 to 1 around 3.887 mhz. But, when we put the
>analyzer on the antenna, it shows the lowest SWR to be about 1.3 to 1 at
>3.887 MHZ, but the SWR's skyrockets quickly on either side of that null to
>infinity on the lowest part of the band, and to over 8.1 to 1 on the top of
>the band.
>
>With my 160 meter sloper, my lowest SWR is about 5 to 1 at the very bottom
>of the band, according both to my TW1 and the TS590 SWR meter, but the
>needle on the analyzer doesn't even budge when tuning through the entire
>band, and stays up at some ungodly figure of an SWR of about 20 to 1.
>
>I just checked for a short on my coax feed lines, and there does not appear
>to be any problem there.
>
>We are using fresh batteries in the analyzer which were just bought tonight.
>
>Are we perhaps not adjusting the analyzer correctly?
>
>I am sure that, to some, all of this seems very elementary, so please bare
>with me while I do some learning here.
>
>73 from Tom Behler: KB8TYJ
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