Hi Tom,
I believe you can just fold back the end of your wire on itself at the end
of your sloper to adjust the length rather than cutting it, that way, you
can again make it longer if necessary.
Also, keep in mind that these antennas are compromised as to bandwidth.
I understand the high end of your sloper is affixed to a 40 foot mast on
your garage roof. How did you ground that end of the sloper? If you don't
have a good ground perhaps this could be causing problems!
Howard #3, W A 9 Y B W
----- Original Message -----
From: "Tom Behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, November 11, 2011 7:50 PM
Subject: Re: Need helping making sense out of contradictory SWR readings
> Pat:
>
> Thanks for the re-assurance.
>
> I guess my question is why the analyzer readings are so different,
> especially on 160?
>
> I guess I just thought the analyzer would be more accurate and closer to
> the
> readings I was getting on the TW1 and TS590 than is the case.
>
> 73 from Tom Behler: KB8TYJ
>
> ----- Original Message -----
> From: "Pat Byrne" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Friday, November 11, 2011 8:39 PM
> Subject: Re: Need helping making sense out of contradictory SWR readings
>
>
>> Sounds reasonable Tom. All of the eighty meter measurements show a
>> dip at 3887 and the actual numbers shown are probably acceptable;
>> none of the test equipment is professional, after all. My guess on
>> 160 is that the MfJ just sees the readings higher and in fact your
>> antenna is resonant somewhere below the band!! It might well make a
>> nice standby antenna for WGN!! Hopefully the 590 can handle the SWR
>> with the internal tuner or your external tuner should do the
>> job. And perhaps remove a couple of feet from the 160 wire and see
>> how that does.
>> Good luck.
>> Pat, K9JAUAt 07:28 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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