Force 12's own website says their more recent coil-loaded Delta 240 is
intended to replace the older linear loaded EF-240S, their explanation
"The most difficult aspect of the antenna was tuning the elements to the
proper frequencies for maximum performance. This is because the linear
loading had variances during assembly." see
Several reviews on eHam.net additionally report problems with the stiff
Alum-O-Weld loading wires/**/ breaking, so I suspect that also had some
impact on F12's decision to create the Delta 240. In theory, the Delta
240 is similar to the OptiBeam OB2-40 (the choice I made as well), but
the Delta 240 elements are a bit shorter and I'm sure the OptiBeam is
more ruggedly built.
> I'm not sure that linear loading is as efficient as some manufactures claim
> and some models require a lot of adjusting of the linear loading wires for
> the antenna to perform properly. I personally prefer a loading coil and
> when looking for a small 2el beam for P40A, I choose the OptiBeam OB2-40.
> The coils are massive, the antenna is well constructed and easy to put
> together. My second choice (actually first choice if budget ruled out the
> OptiBeam) would be the Cushcraft XM240.
> John KK9A
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