I tend to agree with you Jim, except for an important proviso. If we
could all produce a cookie-cutter implementation of a professional
transmitter building, single-point entry panel ground, etc. then it
wouldn't require much to do that. Where it gets messy, and where this
history major stops, is when you know that something - some aspect of
your installation - isn't ideal, so the question is, "what's ideal
enough?" or "will that compromise my installation too much?"
I will still disconnect. The big change I made in my installation after
my one direct hit was to get rid of my wired network, because it was
that which caused 98 percent of the damage in the house through induced
voltage. I know because I saw my network cards *afterward*
73, Pete N4ZR
Check out the Reverse Beacon Network at
http://reversebeacon.net,
blog at reversebeacon.blogspot.com.
For spots, please go to your favorite
ARC V6 or VE7CC DX cluster node.
On 7/8/2013 10:52 AM, Jim Lux wrote:
On 7/8/13 7:21 AM, Pete Smith N4ZR wrote:
I'll take those odds, and repeat - unless you are prepared to spend
totally disproportionate amounts of money, or have the EE smarts to do
it yourself, and the physical circumstancesto do everything optimally,
you are begging far more hurt by staying connected.
For every lightning hit 10 miles from a storm, there are probably a
thousand that are well forewarned. If you're looking to protect the
Space Shuttle, that's one, thing, but...
I think, though, that the level of EE smarts required isn't all that
high, at least for the builder. What we need is something comparable
to the Motorola and FAA docs (which are based, for the most part, on
good engineering) but which is oriented and engineered towards the
radio amateur. A set of recommendations, based on science and well
understood engineering, that is applicable.
We're different than a land mobile installation or a control tower.
Maybe the challenge is that we haven't adequately described exactly
what that difference is, so that the engineering process can be done.
There's plenty of anecdote out there. And there's plenty of R56 and
FAA manual inspired ham installations out there. The real question
is, what parts of those 24/7 type installations aren't really needed.
There's an awful lot of "I built X, and it works for me", which as far
as lightning protection goes is in the same category as "worked 100
countries DX" is for antenna design.
In the non-hobby world, recommendations like this get produced by
putting up proposals, letting knowledgeable folks shoot at them,
grinding through the cost/benefit analysis and documenting that
analysis so that subsequent users can make the trades for themselves,
etc. Sometimes, there's some experimental data needed. It's a slow
process. Look how long it's taken for vertical radial field design to
move away from the AM broadcast Brown, Lewis, Epstein (BLE) paper
based approaches. Lots of analysis, lots of test data from folks like
Rudy, N6LF, etc.
(In many ways, the radial issue is similar to the lightning issue.
The original BLE goal was to come up with something that could be used
in a cookbook way and always meet the FCC performance requirements. It
wasn't necessarily intended to optimize the length of the radials, the
diameter of the conductors, or minimize cost of copper or labor.. It
was was a system engineering thing: do this, and you don't have to
spend the money on field proof of performance tests for a
non-directional installation)
A definite complicating factor for the ham world is that hams have a
penchant for changing their equipment configuration much more
frequently, and they also use an amazingly wide variety of equipment,
not all of which requires the same transient suppression techniques.
In fact, (although I don't know of any examples), I'd bet that there
are cases where a transient suppression technique for equipment A is
actually the exact wrong thing to do for equipment B.
Maybe that's why one needs the individualized EE smarts?
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|