Newsgroup sci.engr.surveying 3235

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Je cherche des correspondants pouvant disloguer en franscais. C'est moins fatiguant...
Gilles Legault glegaul@ibm.net

I'm looking all over the Web, Archie and FTP for
the CORPSCON package.  A friend of mine had his copy corrupted by his
son, who likes to experiment with electro-magnets. :-)
Any URLs would be greatly appreciated. 
I've already checked COGS, USACE, and BLM, but I didn't find it.   My
friend needs to perfom geodetic conversions, among other things.
Robert Burris
Moonlight Cyber
fossil204@netins.net

I've purchased 3 acres of land on which I plan to build a house next
spring.  The lot has a gentle slope of maybe 5 feet, with many trees
on it spaced every 3-10 feet apart from each other.  I'm only
concerned about 1 acre of it because even though the other 2 acres
have a lot of nice trees, the land is considered wetland and I can't
build there.  I would like to get an idea of where the trees are
located on the lot and how the land slopes.  I have never used any
surveying equipment before, but I'm guessing I should be able to
achieve what I want without too much trouble.  Of course the
professional surveyors will do the professional job when the final
plans are drawn up.  I just want to gather some data before winter so
I can get my ideas together on where the house should sit.  If I make
a mistake I'll find out then...
My question is this: Recognizing I'm on a limited budget, what is the
best way to map-out the lot?  It would be nice to rent a fancy laser
range finder with a data logger or something, but I'll have to stick
to a transit that I can rent for $19 a day at the local Rent-All.  (I
never checked the price of something fancy, I just assumed it would
be too expensive to rent).
I went to the library and checked-out a few books on surveying.
After a cursory examination, it looks like "stadia" is the method to
use.  The book says this method has an accuracy of 1:400 which I
interpret to mean plus or minus 3 inches at 100 feet or plus or minus
1 foot at 400 feet.  Is this readily achieved?
I would appreciate any words of advice from the experts.
Thanks in advance,
Greg Cary
gcary@src.honeywell.com
P.S. How much do used transits go for?
-- 
Greg Cary  gcary@src.honeywell.com    office: (612)951-6037  FAX: (612)951-5907

Stephen Rawling wrote:
> . . .
> Anyway....
> 
> I find that the amount of cycle slips with a SSE receiver + compact
> L1/L2 antenna without a ground plane is higher than should be expected.
> I have measured more than one static baseline where an SSE/L1/L2 antenna
> ith no groundplane at one end gave 20-30 cycle slips and a SST/SST
> Geodetic antenna at the other gave no cycle slips. No obstructions at
> either site. Swapping equipment /stations gave same result.
> 
> Processing with Trimvec software circa v4 on data containing lots of
> cycle slips aint good- forget dual frequency unless you have the odd day
> or so to manually fix the massive number of sv/epoch  combinations.
> 
> Here's a one off for you all.
> 
> A SSE receiver in quick start mode cycle slips on every epoch for every
> SV. Start up on a predefined session and all is OK- lousy S/N but that's
> nothing new. Anyone ever experienced that?
> 
> Maybe I had a defective unit??
> 
> ----------------------------------------------------------------------------
> Cheers all
> Steve Rawling
Dear Steve:
I ng would want to look at your antennas ansd receivers. There may be
something "not quite right" with one of the antennas. I would look at
some "zero base-line" sessions to look for differences.
GPSurvey is far superior in "user-friendly" capability than the
venerable war-horse TrimVec. Most of what you describe would probably
not be seen.
Good Luck,
--  
J. Anthony Cavell, PLS            _______              ______
Vice President                   /_____ /   / @ \     /____ /
Navigation Electronics, Inc.    /_____ /===(@ % @)===/____ /
200 Toledo Drive               /______/     \ @ /   /_____/
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