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Re: Cross Boom




hasan schiers wrote:
> I participated in the original discussion of this many months ago and I
> think that the article referred to is being "under quoted". It is NOT just
> mounting the antenna in the "X" configuration. That is NOT what the article
> says. It also REQUIRES careful placement of the driven element distance to
> the cross boom. Doing the "X" alignment is a "necessary" but not
> "sufficient" condition to get the results that the article claimed.
> 
> Two conditions have to be met:
> 
> 1. X configuration

The article does say this.  Mounting the elements in a + configuration can 
"see as much as a 10db loss in gain and the circularity would be nil."

> 2. Distance from the feed to the cross boom

The article does say to avoid mounting the boom 1/2 or 1 full wavelength 
from the driven element.

As a third requirement the article says to "saw off any excess cross boom."

I think I said all three of these in my original reply.

> Many people have testified anecdotally to the metal cross boom working. The
> work of the WA5 in the article made careful measurements. I wouldn't
> hesitate to try it, but follow the instructions in the article assiduously.
> The half-baked representations I have seen discussed lately are unlikely to
> produce the "tenths of dB" performance hit described by the original author.

The author's test was done about 1993. I have used this configuration since 
1981 or 1982.  It has worked fine here and I have had reports of it working 
fine for others.

> My comments aren't to discourage the metal cross boom approach. The article
> convinced me. However, let's not forget the second requirement.

I didn't omit the second requirement.

> ...hasan, N0AN

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