Tom,
Does your friend have access to an antenna analyzer? A problem with
short antennas for 160 is narrow usable bandwidth. Perhaps your little
slice of SWR heaven is outside of the band and pruning or lengthening is
needed.
Although I use a different antenna, here is my situation: 2:1 bandwith
points at 1.835 and 1.855. Above and below these points the swr rises
to 6:1 at 1.800 and 1.900. if my 20 khz sweet spot was out of band due
to improper antenna length, it would take a bit of effort to get it right.
BTW, your 2:1 bandwidth may be even less than mine. I hope you did a
swr check every 5 khz or so across the entire band. If you only do a
few checks, say at 1.8, 1.85, 1.9, 1.95, you could have missed the point
of lowe swr and not realized it.
Good luck, hope to see you sometime on 160,
Steve KW3A
On 12/17/2010 9:52 PM, tom behler wrote:
> Hi, all.
>
> As some of you know, I have been struggling witha Carolina Windom 160
> Compact installation over the past few weeks, with little success,
> especially when it has come to getting on 160 meters.
>
> The lowest SWR I could get on the band was about 8.0 to 1.
>
> Jim Thompson from RadioWorks (the company who makes the antenna), is trying
> to help me troubleshoot the situation, and he has some ideas which a ham
> friend and I are going to try tomorrow, weather permitting.
>
> Anyway, one quick suggestion he made to me was to take a coil of about 100
> feet of RG8X coax, and put it between the transmitter and my Tentech 238A
> manual tuner. He said that this length is about a quarter wave on 160
> meters, and might get my sWR down some.
>
> Well, I did this, and it took the SWR down to about 5 to 1 in the center of
> the band--around 1.850 MHZ.
>
> The antenna still wouldn't tune with the auto tuner in the TS480, but it
> actually tuned with the Tentech 238 manual tuner.
>
> I realize that all I was doing was reducing the SWR by introducing loss into
> the antenna, but I thought I'd try to make a few contacts anyway, just to
> see if it would be possible.
>
> The Canadian RAC contest is going on this week-end, so I made 2 CW contacts
> with no trouble at all. Then, for the heck of it, I went to the SSB portion
> of 160, and made a contact with an Ontario station using only 100 watts. I
> asked for an honest signal report, and he says I was 10 over S9 into
> Ontario.
>
> This surprised the heck out of me, since I know the antenna can't be that
> efficient, but if nothing else, I can now say I've been on 160 meters for
> the first time in my ham career.
>
> Now, if I can get the antenna itself to perform better, without taking such
> crazy measures, I'll be in good shape for the NAQP contests in January.
>
> I know that I have reached this milestone in a rather unorthadox way, but I
> just felt the need to share it with my fellow list members.
>
> I'll let you know how things go tomorrow when we get back to some real
> antenna tweaking.
>
> 73 from Tom Behler: KB8TYJ, Big Rapids, MI
>
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