[Elecraft] To ground or not to ground

[Ron D'Eau Claire]

Normal practice is to connect the "ground" to the station ground buss. The
station ground buss may be connected to a ground system at the base of the
tower or somewhere near the station, provided it is ALSO tied directly to
the AC mains ground for the structure. The point is to be certain there is
but ONE mains ground for the structure and the station **without** relying
on connections from the coax cables to the chassis to the mains outlet
ground. 

Also, external devices normally have a seamless enclosure with only one side
that opens for access to internal components. Normally it must be mounted
with the side that opens facing downward, so rain will not get inside.
Sealing such an enclosure is also possible, if you insist, but be sure to
provide plenty of desiccant inside to absorb the moisture that will condense
out of the air trapped inside unless you have an opening in the side facing
downward. Otherwise you'll see a huge amount of corrosion in spite of
sealing it against salt air. 

I would recommend calking only any seams that are facing to the sides or
upward. 

Also, it is very important to provide "drip loops" on all cables entering
the enclosure. Good designs have the connectors and any cable openings
facing down since they are not 100% water tight. Drip loops will form
naturally for any conductors coming from above. Be sure to run conductors
coming from below to a point above the unit, then loop back down to form a
drip loop. 

You guys in the warm climates really have it tough. Here on the Oregon coast
I'm a few hundred yards from the surf, close enough that it's a constant
background sound, and several times each winter we experience Cat 1 or 2
hurricane force winds blowing in off of the ocean, yet I have yet to
experience salt corrosion on anything. 

Ron AC7AC

 

-----Original Message-----
From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Clint
Sent: Saturday, February 18, 2012 2:51 PM
To: elecraft at mailman.qth.net
Subject: [Elecraft] To ground or not to ground

OK, this is OT, sort of. It will be connected to my K3 so..

I just bought a remote mast mounted antenna switch (Ameritron RSC-8V). It
comes with the center conductor electrically floating when the port is OFF.
It seems to me I would be better off (safer) if the center conductor was
grounded (or had a gas discharge tube or choke or resistor or??? when OFF.

What do ya think?

One thing is for darn sure, I am going to paint the cruddy polystyrene box
and steel brackets (with "Rust Bullet"  FYI), clean off the flux and coat
the PC board before it sees the costal weather! Caulking will be in order
also. Salty rain and spray are nasty even 5 miles in.

 73,

Clint

KI6SSN