Gerry:
The 160 sloper has a loading coil, but we are finding that the SWR is coming
down gradually as we shorten it. I think they supplied 72 feet of wire for
the radiating element of the antenna, and we already have shortened it about
5 or 6 feet.
SWR is now about 4 to 1 at the bottom of the band.
Ran out of daylight yesterday evening, so will do more today, hopefully.
73 from Tom Behler: KB8TYJ
----- Original Message -----
From: "Gerry Leary" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, November 13, 2011 6:33 AM
Subject: Re: Need helping making sense out of contradictory SWR readings
> Tom, do either of the antennas have a loading coil or condensers? If they
> do there may be a short there.
> ----- Original Message -----
> From: "Tom Behler" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Friday, November 11, 2011 6:28 PM
> Subject: Need helping making sense out of contradictory SWR readings
>
>
>> 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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