Tom Haavisto wrote:
> Hi Doug
>
> In doing some research on various antennas, the half-sloper was
> described in various texts as a "bastard antenna". As you indicated,
> works well for some, not well for others. One person spent quite a
> bit of time with EZNEC trying to figure out what was going on with
> this thing. What he finally surmised was that the tower is the active
> radiating element, and the sloping wire tunes it. The direction the
> wire slopes is of minor importance - you get a slight bulge in the
> pattern, but no null off the back.
>
> One he figured the tower is the radiating element, the next step was
> to add radials. I added quite a few, and found this antenna to be a
> good performer. Its an easy antenna to install, and may well be worth
> trying.
>
>
> The biggest thing is to get a decent SWR, and this will vary based on
> tower height, top loading, attachment point and angle of the sloping
> wire. I got lucky - I have 5 element 10 and 15 monobanders on top of
>
I was able to easily tune mine on 160 by simply pruning the sloping
wire. It was cut to length by formula and like all wire antennas only
took a tiny bit of pruning to get on frequency.
73
Roger (K8RI)
> a 64 foot Trylon, and the sloping wire is about 45 degrees, attached
> about four feet from the top. It is definatly vertically polarized.
> I put up an inverted vee off a 48 foot tower about 200 feet away from
> this, and was listening to a local who was using a horizontal long
> wire about 15 feet off the ground, 30 miles away. S9 on the inverted
> vee, and barely readable on the half sloper. Have noted similar
> differences between DX (vertically polarized) vs horizontal (close in
> stuff).
>
>
>
> Tom - VE3CX
>
>
>
>
> On Mon, Nov 10, 2008 at 10:43 AM, Doug Renwick <ve5ra@sasktel.net> wrote:
>
>> Tom,
>>
>> Interesting comment on adding radials. I use half-slopers from my 110'
>> guyed self-supporting tower on 160m. They work really well but I don't
>> use any radials. I am also aware that half-slopers work well at some
>> qths and not well at all at other. Maybe the answer is to add radials.
>> How did you discover this radial thing?
>>
>> Doug
>>
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