Hi,
I met a person some time ago that claimed that he has measured
significant site variation due to moisture absorption of wooden enclosures
in the winter months.
That person is Michael Heckrotte of Precision Research. He
is an expert in the area of antenna calibration and
site qualification and could probably give you a ballpark estimate
of what type of variation is caused by wood moisture content, metal
fasteners, etc..
Assuming his business location has not moved, you can phone Mike
at (408)253-6994 or fax him at (408)253-8011. His business address
is 21987 McClellan Road, Cupertino, CA, 95014.
I know of several people that use his consulting and calibration services
and
he comes highly recommended. I am not sure what are his consulting
fees.
Regards,
tony_fredriks...@netpower.com
----------
From: Gabriel_Roy
To: Bill Franklin JR
Cc: JTOLBERT; emc-pstc
Subject: Re: O.A.T.S. enclosure
List-Post: emc-pstc@listserv.ieee.org
Date: Thursday, October 03, 1996 5:01PM
All the ones I have seen have used plastic bolts instead of metal nails,
also
the antenna mast was always located outdoors, outside the building (except
for
the ICL site which is underground in the UK).
Gabriel Roy
Hughes Network Systems
MD
To: JTOLBERT @ genicom.com @ SMTPGW; emc-pstc @ ieee.org @ SMTPGW
cc:
From: wfranklin @ bb-elec.com ("Bill Franklin JR") @ SMTPGW
List-Post: emc-pstc@listserv.ieee.org
Date: 10/03/96 01:26:27 PM
Subject: Re: O.A.T.S. enclosure
SMTP Headers: Headers
Hello,
We built a 3 Meter site a few years back - maybe some of our
experiences will help. We built it using all wood framing with nails
no bigger than 16 penny (about 2" to 2 1/4"). We have two windows
with plastic frames (to let in some light), a ridge vent that is made of
cardboard (for ventilation), and a ridge pole that is made of plywood.
The outer surface is plastic house siding. We used asphalt roof shingles.
The thing looks like a ski slope with the peak at the maximum
for the adjustable antenna. We had no problem staying within the
4 dB limits. We have passed every year so moisture must not be too
much of a problem.
We have a different problem in that the water table is very high here
and we couldn't put a basement under our site, so we built up. Our
ground plane is eight feet off the ground. It works fine for a 3
Meter site but there is no way to move outside and use it as a 10
Meter site. That also makes the building very very tall.
Bill Franklin wfrank...@bb-elec.com
>
> Winter is coming and Hurricane Fran took my fabric-type Air Support
> structure with him leaving my 10 meter "all-weather" Open Air Test Site as
a
> "fair-weather" site. :>(
>
> How about passing on your experiences regarding problems with any
particular
> types of PERMANENT building schemes to enclose RFI test sites. What
(other
> than the obvious conductive types) materials will erode my site
attenuation?
> Will I have to be concerned about things such as moisture content of the
> framing?
>
> What types of designs yield a robust structure, yet allow for the 6 meter
> high antenna clearance so the antenna can be moved from the 1m position to
> the 10m position without dropping the mast?
>
> Thanks
>
> Joe
> Joe Tolbert
> GENICOM Corp.
> Waynesboro, VA
> jtolb...@genicom.com
>
>
