OB40-M weighs 35 kg (77 lb) and by specs it covers all of 40m with SWR < 2.
A shortened Moxon from JK Antennas: JK 402-Piccolo with coils weighs 88 lb
and covers only 250 KHz. A full size Moxon JK420T weighs 125 lb and covers
all of 40m. Both antennas have 100 mph ratings.
Judging by the size, OB40-M uses coils but has higher bandwidth than the
equivalent JK. Not sure why.
OB2-40m is about $2100 from DX Engineering and JK 402 Piccolo
around $1700.
Ignacy NO9E
On Thu, May 20, 2021 at 4:26 AM David Gilbert <ab7echo@gmail.com> wrote:
>
> I have owned an OB2-40 (the non-Moxon version) for ten years and it has
> held up just fine to ridiculous wind gusts on my southern Arizona
> hillside. The antenna is built like the proverbial tank and I've
> measured wind gusts as high as 100 MPH. The wind gusts are brutal here
> for about three months every spring, to the point that I usually can't
> bring myself to even look at my antennas when I hear one of those
> mini-tornadoes come roaring down the side of the mountain. I even
> watched one lift my teenage son about two feet off the ground while he
> was weedwacking part of the lot. It picked him up vertically (with the
> weedwhacker still in his hands), moved him about three feet laterally,
> and set him back down. This is no exaggeration ... I saw it with my own
> eyes.
>
> The OB2-40M is listed as having the same overall weight as my OB2-40 and
> the construction looks identical, except of course for the Moxon
> wingtips. The wind area of the OB2-40m is 5.9 sq ft versus 6.8 sq ft
> for the OB2-40 and I would think that the Moxon configuration adds a bit
> of additional stability, so I don't see why it wouldn't hold up as well
> or better than my antenna.
>
> 73,
> Dave AB7E
>
>
> > On Wed, May 19, 2021 at 7:34 PM Michael Tope <W4EF@dellroy.com> wrote:
> >
> >> One of the radio clubs I belong to is interested in buying an OptiBeam
> >> OB2-40M two-element 40 meter Moxon Yagi. Optibeam is kind of vague on
> >> wind survival specifications. Their website indicates "Windload at 130
> >> km/h 430 N / 0,54 m² / 5,9 feet²". To me that implies the
> >> antenna is designed to survive 130 km/h winds (80.7 MPH), but it doesn't
> >> actually say that. The antenna is going to be installed at a Southern
> >> California QTH at a fairly low elevation, so icing is extremely
> >> unlikely. However, the antenna will be installed on a high narrow ridge
> >> that lend itself to very high uneven (shearing) winds when we get the
> >> occasional winter storm or Santa Ana wind condition.
> >>
> >> Anyone out there using one of these antennas? I am curious what you
> >> think of it in terms of performance and reliability?
> >>
> >> Thanks and 73,
> >>
> >> Mike W4EF.................
>
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