"DSK" wrote in message

Not at all. You made an incorrect statement, probably an oversight by not
being quite technical enough. It's OK, nobody expects you to write a book
on how GPS works, and all the things it can (or can't) do, for the benefit
of a cretin like Bubbles/bitty-bill.

I prefer to assumed you misinterpreted my statement.... but let's not
quibble!.... I thought I was wrong once... turned out I was mistaken. :-)

Is that with optimum constellation geometry? I should think some of the
fancy wave interpolation antennae units could do better than that, but I
don't know (they're a bit out of my field & price range).

Simple cloud cover will greatly affect accuracy on our units. No matter what
the optimum accuracy potential is... the end result will be affected by
climatic conditions. One of our site units costs 80K. We had a 2 million
dollar unit shooting ball targets to verify 5 mm accuracy. It failed to
produce the accuracy and tolerences required.

CM