[TowerTalk] "K" factor gets sillier
Sat, 22 Jul 2000 16:18:18 -0700
Pete Smith wrote:
> Gee, Kurt, I'm not with you on this one.
I understand what you are saying Pete!
And I don't take great issue with your perspective!
I think there is a bit more to it.
As usual, I don't explain myself very well in this instant medium.
We are still friends!
I think there are some underlying assumptions in your position that
might be flawed.
We can't assume that everyone that used a Yaesu rotator properly loaded
the rotator according to the old "K" factor and we can't assume that all
of the antennas that were put on these rotators were equal in their
behavior under wind loading. If you'd seen what I've seen, you'd know
that there is a disparity between commercially offered antennas on the
order of a magnitude of 10, with respect to behavior under wind loading.
It is a huge deal. But, we're not gonna go there till we straighten out
the much SIMPLER antenna area fiasco.
I know you are capable of figuring it out, but I'd bet you are unique.
I'd wager that most rotator purchases are based on budget and neat
features, and most people don't know how their antennas behave under
wind loading. Ya wanna do a poll, I'll buy the beer!
The Yaesu database does not represent the history of a few of us that
would take a Sat afternoon to consider the problem, it represents
literally thousands of cases involving antennas with unknown behavior
and people that never gave more than a moment of thought to this
Someone needs to talk to the Yaesu engineer responsible for the new spec
to find out how they arrived at this new approach, to really know what
I'm not saying "WHAT" they have done is correct, I have no insight to
pass judgement on that!
I'm saying there is nothing wrong with the approach WHEN IT IS DONE
Surely, there is someone at Yaesu with the goods to do it right! It is a
trivial matter, when compared to designing and building the line of
products they provide us.
No doubt, Yaesu is tired of getting pounded by their customers about
rotator failures, and have changed the spec's to treat the problem.
The apparently "excessive" new approach may simply reflect antenna mfgr
and user malpractice, beyond Yaesu control. It makes no difference from
the Yaesu perspective, their goal is to not have any more unhappy
customers for any reason. If getting some guy to turn his C3 with a
G-2800 is the result, then fine, their goal is accomplished. No more
If I was doing it, I'd multiply the mast weight x it's radius in feet to
be consistent with the rest of the approach. I'd do the thing for every
reported failure, and factor in the useful service life represented by
each case. Then, if I wanted to be really clever, I'd factor in a "use
factor", whether the guy was a contester, a DX'er, or a rag chewer.
Surely the contester's useful service life is going to be ~1/2 of the
DX'er. The rag chewer is some fraction of the Dx'er. AD Nauseum.....
But, I'm not doing it, and I do not have access to the database. Nor do
any of us around here.
Roger Cox at Hygain was very forthright in explaining what the
"Effective Moment" meant and what it represented. Until someone from
Yaesu comes forth and explains their situation, I'll assume it
represents their honest effort to remedy the problem.
We could do our own right here on TowerTalk. There are a few thousand
data points represented by the folks that hang around here. Bet you a
paycheck that never happens! Till it does, we have to rely on the guys
that make their living, making these things for us!
I guess my point is that before we go beat up on Yaesu for their new
method, we ought to know more about how many of the points in their
database were corrupted by malpractice. It might be very enlightening!
They may have done a very good job of quantifying how we (antenna
manufacturers & hams in general) are abusing rotators! Till we
understand what is really going on, we have no basis to fault them!
There is simply not enough information to make a call.
Whew! It's hot out there, thanks for the opportunity to cool off, back
out there to get some more done....
Back to the venerable value of the Db...
73, Kurt, K7NV
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