That's what I've always been led to believe Steve. Almost put one up
when I had that tower but missed my opportunity.
PatAt 01:43 PM 11/28/2012, you wrote:
>The other issue with a sloper, or at least with some of them, is inadequate
>counterpoise. I don't think Tom has much of a counterpoise and the ones
>I've seen require some kind of capacitive tophat i.e. mounting them on a
>tower below a tribander.
>----- Original Message -----
>From: "Pat Byrne" <[log in to unmask]>
>To: <[log in to unmask]>
>Sent: Tuesday, November 27, 2012 11:07 PM
>Subject: Re: Cobra antennas
>
>
> > Just thinking out loud Tom. Perhaps the missing half of the sloper
> > is inadequate for 75 meters. Perhaps the angle of the wire effects
> > the minimum SWR. But, how does the antenna work? If you didn't know
> > that the SWR was high would you suspect that your compromise antenna
> > is letting you down? Can you wangle enough space to get up a
> > temporary 75 meter dipole and be able to switch between the two wires
> > to see the difference? Would that tell you anything? I believe that
> > you have found that adding coax to the feed line lowers, in theory,
> > the SWR. I guess what I am asking is are you being misled by an
> > arbitrary meter reading that may in fact not mean too much. And
> > certainly I can be wrong as can be and that your gut and your meter
> > are telling you that the antenna stinks!
> > To end all of this rant; when I was a kid in the hobby I put up
> > antenaes cut to a quarter wave, particularly on forty meters
> > according to the formulaes and, knowing what I know now, they were
> > probably way too long since they were pretty low. But I didn't have
> > an SWR meter. I had a Windem fed with 300 ohm TV twin lead which I
> > now know was an awful match but the PI network forced power somewhere
> > so I was convinced that I had a great antenna. I guess that
> > ignorance was bliss! Perhaps if there are other hams in your close
> > area, you can work QSOs with them and see at a distance how your
> > signal compares. Okay, I'll stop sounding like an old fart!!
> > Good luck my friend. Antennaes are really a fun part of the hobby.
> > Pat, K9JAUAt 08:22 PM 11/27/2012, you wrote:
> >>Hi, all.
> >>
> >>Please forgive me, since I know this antenna has been discussed on the
> >>list
> >>before in various forms. But, I am needing some basic info from the
> >>perspective of someone who has actually used one.
> >>
> >>Here's the deal:
> >>
> >>As some of you know, for reasons I can't quite understand, I have been
> >>having trouble getting my W8AMZ 80-meter half sloper to work well on 80
> >>meters. The SWR's for most of the band are at least 3 or 4 to 1, except
> >>for
> >>about 100 KHZ between 3.850 and 3.950, where they are below 2.1 to 1.
> >>Based on the better luck I'm having with the 160-meter sloper made by the
> >>same company, I'm convinced that there is either something wrong with the
> >>antenna, or something in my installation that is throwing things off. Tom
> >>(W8AMZ) himself has actually volunteered to come to my home QTH sometime
> >>to
> >>try to assess things. He is about an hour and a half from me, so it's a
> >>trip that will have to be planned by him when he has the free time.
> >>
> >>Since I'm not sure when that trip will occur, I'm thinking about other
> >>alternative antennas that might be easily put up and relatively
> >>inexpensive. I don't have a lot of room to put up another antenna, but I
> >>probably could handle an antenna that was approximately 100 feet in
> >>length.
> >>Again, my main band of concern is 80 meters.
> >>
> >>I believe that some folks on here have used an antenna called the Cobra,
> >>or
> >>Cobra Lite. If you have used this antenna, could you please describe it
> >>to
> >>me, tell me how you put it up, state any special installation
> >>considerations
> >>I might need to take into account, and tell me whether it worked well on
> >>80
> >>meters?
> >>
> >>I am not sure of the price of that type of antenna, but I'm sure I could
> >>get
> >>that info from the Cobra web site via a google search.
> >>
> >>I simply don't want to spend money on yet another antenna, unless I have
> >>some assurance from someone who has actually used it, that the antenna
> >>might
> >>be a good alternative for me.
> >>
> >>Thanks, and 73 from Tom Behler: KB8TYJ
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