At 11:56 AM 3/18/02 -0500, K4IK wrote (re the Cushcraft ASL-2010):
...
>20 meters: about 1 dB more gain and about 3 dB F/B for the C3E
>17 Meters: about 3 dB more gain and about 10 dB F/B for the LP
>15 Meters: a toss up (< 2 dB F/B for the C3E)
>12 Meters: about 2 dB more gain and about 10 dB F/B for the LP
>10 Meters: about 1.5 dB more gain and about 3 dB for the C3E
>
>Based on Force 12's claimed specifications for the XR-5, the
>XR-5 and ASL-2010 should be a toss up on 17 and 12 meters.
>The ASL-2010 has eight elements on the 18' boom vs. 10 for the
>XR-5. Models of nine or ten element log periodics on an 18'
>boom show gains +/- <1 dB of the C3E and F/B within 3dB of the
>C3E (and claimed XR-5 specs) depending on band.
>
>Since the "selling price" (www.aesham.com) for the ASL-2010
>is $220 less than the "introductory price" (www.force12inc.com)
>for the XR-5, an 18' boom log periodic is a very competitive
>choice for someone who would like to cover five bands with a
>single antenna.
Now that's interesting. I went looking for M2 prices, and never thought to
look at the Cushcraft. That *is* a useful difference.
I still wonder about the weight and, particularly, the complexity. Trying
to feed every element with relatively precise phasing strikes me as fairly
challenging mechanically. Did your model use transmission lines, or did
you calculate the phasing of the feed at each element and use that figure?
Did you also work loss resistances into the model, if only to see how
significant they would be?
I wonder how the Cushcraft antenna has stood up in real life. My opinion
of ham LPDAs is somewhat jaundiced because a friend's Tennadyne T-10, when
taken down after 7-8 years, was so riddled with fatigue cracks that there
was nothing to do but throw it away. Granting an N of 1 and only one
brand....
Oh, in fairness I should note that my friend was very happy with the
antenna while he had it, and bought another brand LP for his new QTH.
73, Pete N4ZR
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