On Sun, 12 Mar 2006 14:40:36 GMT, Brian Whatcott
wrote:

On 3 Mar 2006 14:57:52 -0800, "purple_stars"
wrote:

//
but do you still use RDF ?

[brian]
As your question didn't pull any responses, I'll chew the rag, for
what it's worth.
There are at least four DF systems in use.
///
Brian Whatcott Altus OK
p.s. GPS made a lot of aids obsolete, right there.

Holy smoke!

Next time I looked there were dozens of responses, all BEFORE my note.

Ah well....


Brian Whatcott Altus OK

There is a bit of a leap when though if you don't point
out that all those same inaccuracies also apply to the traditionl forms

of navigation.

Indeed they have their problems; what I was trying to point out is they
are direct observations emitted from your boat, not dependent on a
chart (excluding RDF g). Much more like the Mark I eyeball and
earball than GPS is.

There is a bit of a leap when though if you don't point out that all those
same inaccuracies also apply to the traditionl forms of navigation.


Indeed they have their problems; what I was trying to point out is they
are direct observations emitted from your boat (well, not RDF g).
They still provide useful information even if you have no chart. Much
more like the Mark I eyeball and earball than GPS is.

The technique is still valuable. I.E. If you frequent an area plagued
by occasional fog, RDF observations recorded during periods of good
visibility would be useable when conditions were bad, even if GPS and
actual charts disagree. This presupposes that you can survive the trip
on a good day using traditional methods.

Preserving options is a viable method. Relying on a single method that
can not be absolutely guaranteed in a case of dead batteries or gps
instrument is an invitation the fates will not ignore indefinitely.

Terry K

The technique is still valuable. I.E. If you frequent an area plagued
by occasional fog, RDF observations recorded during periods of good
visibility would be useable when conditions were bad, even if GPS and
actual charts disagree.

Right on. RDF is most useful if the beacon is an actual marine navaid
on structures of interest, like an entrance jetty, which you can "home
in" on. Then, when fogbound and "close-in" , i.e., a few hundred
yards, it can tell you which side of the item you're passing on,
without benefit of a chart. It's less reliable when you're far
offshore or the signal emitter is not near shore (like a commercial
radio station antenna inland), because of the bending of the apparent
direction of the antenna by topography, etc.

Personally, I'm still using GPS as my backup to check my visual/radar
fixes (which I consider to be more "real world" true) until all Charts
have been corrected using GPS/DGPS readings.

Bingo!

I've been lurking on this thread waiting for someone to bring up the
key problem with GPS: sure it's mighty-fine accurate, but it's just a
lat-lon, *useless* until related to navigational features of interest
somehow, usually by consulting a chart, electronic or paper.

All navigational systems need maps. All maps need frequent updating. GPS is
not an exception to that rule.


Some
things can't be accurately plotted, some deep-set buoys can swing on
their moorings by a half mile, for example.

If you have GPS why in the world are you navigating to buoys? GPS replaces
the need for a buoy.



What GPS has done is allow nitwits to navigate right on the money, most
of the time, and not develop other navigation skills.

Its appropriate that you understand the word "nitwit" after you tried to use
GPS to navigate to a buoy above.

Used to be natural selection took care of them sooner or later.
Cruising's going
to hell...

I was wondering why you were trying to make technical arguments when you
clearly have no technical understanding. Then this last sentence explained
it all. You just want to complain that the world is going to hell. Your
post is nothing more than an emotional outburst from an old washed up guy
who is growing angry. Everything else in your post should be ignored as
nonsensical.