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SGC Inc. SGC Building, 13737 S.E. 26th St. Bellevue, WA 98005 USA
P.O. Box 3526, 98009 Fax: 425-746-6384 Tel: 425- 746-6310 or 1-800-259 7331
E-mail: [email protected] Web site: http://www.sgcworld.com
© 1998 SGC Inc
SG-235 Manual
By the way, this is why we don't like to use aluminum ground wires as radials.
Just as when aluminum is used in house wiring, several gauges larger are
needed to carry the same amount of current the same need applies here.
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g .. The fourth kind of ground fault you may encounter
occurs where the ground is not properly bonded to the coupler. We go to con-
siderable effort to make sure the stainless steel ground stud is well connected
to the coupler.
Particularly in automobiles and aircraft, a single ground connection
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o. It is mandatory that at least two ground bolt connections are used.
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s .. The fifth situation to check for is what we call
Òdangerous assumptionsÓ about the ground system. When you bond from the
antenna coupler to copper or iron water pipes, you might make an assumption
t h a t t h e w a t e r p i p e s a r e a g o o d g r o u n d . B u t i n m a n y i n s t a l l a t i o n s ,
copper pipes are used in the building but a plastic main connects to the
municipal system outside the service entrance. So much for a good ground.
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The key to getting the most out of your Smartuner is to realize the antenna
begins right at the high voltage screw on the SG-235 case. In other words, this
is the feed point of your antenna system. Failing to install your coupler
accordingly will result in unsatisfactory operation. With this concept in mind,
you can easily avoid some of the common troubles with a properly planned
installation.
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u tt p
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commonly asked question about the coupler and is the most misunderstood. Let
us reiterate: The Smartuner was not designed to feed a piece of coax.
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e .. Stray ground capacitance is the next largest
cause of malfunctioning installations. If you have a long lead wire from the
coupler to a feed through (on a wall or bulkhead), you significantly increase
your chance of problems. Wire running parallel to a grounded surface may
represent a significant capacitance to ground and, just as with coax, this will
cause problems.
To give you an idea how these two points can cause problems, let us relate an
incident which happened in late 1992. A Smartuner user had a coupler
installed in a mobile ham radio installation. The coupler could not find a lock
on several bands. After going through his installation carefully, the user
called SGC for technical support. This user was nearing wits end.