[600MRG] WX De-Tuning 630 Meter Antennas

[Pat Hamel]

Frank,
Your enclosure will be determined by your surroundings and finances.
I used a big plastic storage bin mounted on some posts in the ground from a
failed vertical support. The plastic enclosure has a single weep hole in the
bottom and is dark in color due to green plastic spray paint. The press-on
top has stayed on with the application of sticky ignition silicon grease.
Here on the Gulf Coast we get tropical downpours and it has had snow with no
bad effects.
By mounting it on it's side about four feet off the ground, I can work in it
without a backache. It has held a loading coil which was wound on a "large"
dollar store white plastic flower pot, but hanging the loading coil at the
top of the radiator below the 11-wire top-hat gave me better signal reports.
When we moved from above 500kc to 472kc I added a small remotely tuned
loading coil back in the box.
I hope this helps,
73,
Pat WD2XSH/6



-----Original Message-----
From: 600MRG [mailto:600mrg-bounces at w7ekb.com] On Behalf Of Frank Lotito
Sent: Sunday, February 08, 2015 5:41 PM
To: 600 / 630 Meter Group
Subject: [600MRG] WX De-Tuning 630 Meter Antennas

For the past few days I have read some interesting 600 mrg posts regarding
the effect of weather / ground conductivity on 630 meter antennas.  I assume
the investigators all have their 630 meter antenna tuners at or near ground
level, at the antenna's feed point.  I further assume the tuners are housed
in some sort of "enclosure."  I have a few questions - Is there evidence
that condensation, inside or outside the enclosure is not a player in the
de-tuning effect?  If the enclosure is somewhat hydroscopic, e.g. wood and
certain types of plastics, how far from the main tuning coil / variometer
should the enclosure be as to not interact with the magnetic field around
the coil? What about the effect of temperature on the mechanical dimensions
of the main tuning coil / variometer? 		 	   		  
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