[Laser] Ramsey Kit Modes

[Jim Moss]

Well, it's simple geometry.  You want to be located at a  point that  optimal for your 5+ grids.
The optimal point (shortest distance average) is very close to a grid line, in the middle of the other dimension.

[][][]
[][][]

consider this arrangement and you are in the geographic middle.  You can work your own grid (1 mile min). the grid N of you (1 mile min) and the corner of each of the other 4 grids (about 30miles each).

If you find that your system "easy" contacts are 25 miles, then offset E or W 5 miles  closer and you have 4 "easy" contacts. But the hard contact is only 35 miles (not 60).

From my experience hillside to hillside LOS with <5mW of laser at 670nM 25 miles is "easy". A good light collector, like a book page magnifier, on the RX side, and a stable pointing device on the TX side results in 599 signals using MCW.  To your eyes at that distance, the laser will look like it's the brightest thing in the whole area (it will wipe out any adjacent city lights, once it is on target).  With a good set of binoculars, we've seen a simple 2-D cell flashlight. (once you find it!)

Jim
N9JIM




________________________________
From: Les Rayburn <les at highnoonfilm.com>
To: Free Space LASER Communications <laser at mailman.qth.net>
Sent: Saturday, January 31, 2009 12:17:12 AM
Subject: Re: [Laser] Ramsey Kit Modes


Jim,
 
Hmmm...I hadn't considered that. Can you explain where the best location (in terms of distance alone) in a given grid square might be to work five grids? In the center? 
 



From: Jim Moss 
Sent: Saturday, January 31, 2009 12:29 AM
To: Free Space LASER Communications 
Subject: Re: [Laser] Ramsey Kit Modes

Les,
Suggest you move the station not too close to the corner, that way you don't have 60 miles.
You will find 25 is pretty easy if it's LOS

Jim
N9JIM





________________________________
From: Les Rayburn <les at highnoonfilm.com>
To: Free Space LASER Communications <laser at mailman.qth.net>
Sent: Friday, January 30, 2009 8:40:01 PM
Subject: [Laser] Ramsey Kit Modes


James,
 
Took your advice and searched the archives for the postings regarding the Ramsey Kit and the XE2 attempt (successful) at VUCC. It appears that the K3PGP "front end" installed on the Ramsey kit might be a good modification to start with. 
 
I saw a lot of your posts, but none of the ones I read indicated how much you'd experimented with long distance work. One critical difference between the XE and our attempts is that we've identified a convergence spot that has easy QSO's with four grids (all within 2KM) and good LOS to a distant fifth grid. Our real effort will be making that long distance QSO. The first four grids should come easily. 
 
Please share with me your thoughts on this approach and others that I should possibly consider. Thanks again!
 
73,
 
Les Rayburn, N1LF
 

 
Les Rayburn, director
High Noon Film
100 Centerview Drive Suite 111
Birmingham, AL 35216-3748 
205.824.8930
205.824.8960 fax
205.253.4867 cell
________________________________
_______________________________________________
Laser mailing list
Laser at mailman.qth.net
http://mailman.qth.net/mailman/listinfo/laser
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.qth.net/pipermail/laser/attachments/20090131/1db94439/attachment.html