A different idea than lug connections, is to use load-center style ground
bars bolted to the metal plate.
http://www.homedepot.com/p/Square-D-23-Terminal-Load-Center-Ground-Bar-Kit-PK23GTACP/100129430
I fully agree this is not up to Bellcore grounding standards. But seems
much more ham-amenable, especially for those of us who unroll many of our
random-gauge radial wires across driveways and lawns on contest weekends
and hook up in cold weather - the clamp screws in the ground bars are
easily worked with a screwdriver in a gloved hand and accomodate any
random-sized-style conductor.
Tim N3QE
On Wed, Feb 4, 2015 at 10:17 AM, Paul Christensen <w9ac@arrl.net> wrote:
> I've long thought about designing a radial plate that addresses some
> significant limitations with currently available product. Specially, every
> commercially available radial plate uses single-hole lugs to attach a
> radial wire to the plate. The problem is that with upwards of 60+ lugs in
> harms way of accidental contact, single-hole lugs are very susceptible to
> rotation and loosening.
>
> In the link below, you'll see a different kind of radial plate that makes
> use of double-hole lugs.
>
> http://tinyurl.com/pykx44x
>
> Around the perimeter of the plate, you'll see 120 paired holes in addition
> to an extra set of corner lugs for system grounding. This is the type of
> ground attachment required at Bellcore hardened facilities (now Telcordia).
> When I was with AT&T Broadband Engineering, every ground bond at its fiber
> optic-hub sites required two-hole lugs to pass compliance testing. Once
> tightened, the lug cannot spin loose. Over time, the connection maintains
> much better mechanical and electrical contact with the plate. A typical
> two-hole lug looks like this:
>
> http://www.alliedelec.com/images/products/datasheets/bm/T_B/70092228.pdf
>
> Although this plate has pairing for 120 radials, the plate can be scaled
> down to sizes of 30, 60, and 90 radials. Each hole is tapped for a 1/4
> inch bolt - which does not preclude use of an additional nut on the back
> side of the plate. The center area has mounting for various angled plates
> to mount saddle brackets, antenna connectors, etc.
>
> Before anyone with a related patent takes issue with this, I not making,
> nor supplying these plates. Rather, the design file(s) will be made
> available to anyone who may wish to use and modify at-will. The user can
> select plate thickness, remove the double lugs and replace with single
> lugs, remove tapping, etc.
>
> Frankly, these plates are just too costly to produce + make any semblance
> of a profit. The plate shown in single quantities from the manufacturer is
> about USD $500. The price of 120 double lugs? One can expect to add $200
> even in large quantities. But the plate price drops quite a bit when a
> lesser number of radials are used and hole tapping is removed.
>
> The purpose of this message is to seek additional input for ideas. I may
> create a set of files that range in a low-to-high manufacturing price,
> depending on interest.
>
> *Please send any ideas directly to me and not the list.*
>
> Finally, we all know that a radial ring can be created using nothing but
> heavy copper wire. I get it. This is for the person who wants a premium
> radial plate with lug connections. Thanks.
>
> Paul, W9AC
>
>
>
>
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