I second the motion to absolutely avoid braid outdoors for any RF site for many
reasons including external rectification issues from corrosion. We even avoid
it indoors at our work comm sites. Commercial radio sites that must meet
vendors' standards like NFPA or Motorola's R-56 guidelines recommend either
insulated-stranded or tinned-bare-solid wire for outdoors. And technically
better than that is to use solid copper strap; however, this has become a
magnet for copper thieves in recent years.
As far as Jim, K9YC's bonding suggestions, it is probably acceptable to do this
daisy chaining on anything that's not connected to any RF equipment like
computers. But for anything connected to RF equipment, daisy chaining violates
the "guidelines" and specs for single-point grounding systems. This may be
acceptable as long as the overall shack has proper lightning protection in all
Jim, K9YC has an interesting presentation on this topic at:
73, de ed -K0iL
From: RFI [mailto:firstname.lastname@example.org] On Behalf Of Dale
Sent: Thursday, December 19, 2013 2:43 PM
To: Peter Laws; email@example.com
Subject: Re: [RFI] DigiKeyer II
You mention use of braid to the ground rod outside. That's OK if the braid is
encased within some sort of weather-proof cover, such as shrink tubing. The
problem with braid that is exposed to the elements is that it corrodes, and
unless you inspect it frequently (at least once per year), you could end with
no connection (or a very high resistance one). If you do not have covered
braid available, replace that run of braid with insulated stranded (the kind
used for electrical work - not welding cable) copper wire. No. 6 or No. 4 AWG
will be fine.
I've been following the thread. Lots of good input from K9YC, and please do
let us know what you find when you reduce power.
>From: Peter Laws <firstname.lastname@example.org>
>Sent: Dec 19, 2013 1:08 PM
>Cc: "email@example.com" <firstname.lastname@example.org>
>Subject: Re: [RFI] DigiKeyer II
>On Thu, Dec 19, 2013 at 10:34 AM, Jim Brown <email@example.com> wrote:
>> Go back and CAREFULLY read what I wrote about bonding everything together by
>> SHORT, FAT COPPER. That means a foot or two of #12 run DIRECTLY from the
>> computer to the radio, another from the computer to the DigiKeyer, another
>> from the DigiKeyer to the radio.
>Done. It's braid from each component (PC, PS, DK, radio) to the
>copper bus bar on the back of the shelf and braid to the rod outside.
>Peter Laws | N5UWY | plaws plaws net | Travel by Train!
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