Mike:
You have a very interesting point here about local broadcast signals.
I happen to live about a half mile from the tower for the only commercial A
M radio station in our little Michigan town. ... It broadcasts on 1460 AM,
with a night-time power of, I believe, 1000 watts.
Are you saying that this is what's messing the analyzer up?
Again, just to be sure I'm understanding you, are you saying ignore the
analyzer, and just go with what my TW1 and TS590 meters are saying?
Obviously, my 160 meter antenna is still too long electrically, so that will
need to be shortened.
But, here's another question: When we put up the 160 meter sloper, I only
had a 100-foot piece of RG8X coax to connect between the antenna and the
rig, which gives me about 40 feet of excess coax. ... Should I cut that coax
to only what I need? Would that change anything?
Again, you are giving me some very interesting observations here.
73 from Tom Behler: KB8TYJ, Big Rapids, MI
----- Original Message -----
From: "Mike Cozzolino" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, November 11, 2011 9:30 PM
Subject: Re: Need helping making sense out of contradictory SWR readings
> 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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