Daily Archives: 9/14/2008

World Map

I’m still playing around with GMT to generate some maps. I’m not sure I’ve really got it figured out, but here is an attempt to draw a world globe with some of the great circles that connect me to the various stations that have received my WSPR beacon messages.



Addendum: Robert pointed out that I didn’t give a link to the GMT tools. Consider this to be the remedy. They are kind of a quirky set of tools that can be used to create very nice output in a number of different projections, but they aren’t the simplest to figure out. I first learned about them from the book Mapping Hacks which is well worth owning.

Progress on WSPR

So, I’ve made some progress on teasing apart enough of the encoding of WSPR beacon messages to write a completely stand alone Python program that will generate the appropriate tone sequence to send out the callsign/grid/power message. For instance, if I type “genwspr KF6KYI CM87 27”, I get:


3, 3, 0, 2, 0, 0, 0, 0, 3, 2, 2, 2, 3, 3, 1, 2, 0, 2, 3, 0, 0, 1, 0, 1,
1, 1, 3, 0, 2, 2, 2, 0, 2, 2, 3, 2, 2, 1, 0, 1, 0, 2, 0, 0, 0, 2, 3, 0,
3, 1, 0, 2, 3, 3, 2, 1, 0, 0, 2, 3, 3, 0, 1, 2, 0, 0, 0, 1, 1, 2, 1, 0,
3, 0, 3, 0, 3, 2, 0, 3, 0, 2, 1, 2, 3, 3, 2, 2, 2, 1, 3, 2, 3, 0, 3, 0,
2, 0, 1, 2, 2, 2, 0, 0, 3, 2, 0, 1, 0, 0, 3, 1, 1, 2, 1, 1, 0, 0, 1, 3,
0, 3, 2, 0, 0, 3, 3, 3, 2, 2, 2, 0, 2, 3, 0, 1, 0, 0, 1, 3, 0, 0, 0, 0,
0, 2, 0, 3, 3, 0, 3, 0, 3, 3, 2, 0, 0, 1, 1, 0, 0, 2,

Which is the 162 bit long code needed to indicate that KF6KYI is operating with an output power of 27dbM, or 0.5 watts.

If I crank up the power to 37dbm (a full 5w on my FT-817), i should use this code sequence.


3, 3, 0, 0, 0, 0, 0, 0, 3, 0, 2, 2, 3, 1, 1, 2, 0, 2, 3, 2, 0, 3, 0, 1,
1, 3, 3, 0, 2, 2, 2, 0, 2, 2, 3, 0, 2, 3, 0, 3, 0, 0, 0, 0, 0, 2, 3, 2,
3, 3, 0, 0, 3, 3, 2, 1, 0, 0, 2, 1, 3, 0, 1, 2, 0, 0, 0, 3, 1, 0, 1, 0,
3, 2, 3, 2, 3, 2, 0, 1, 0, 0, 1, 0, 3, 3, 2, 0, 2, 1, 3, 2, 3, 2, 3, 2,
2, 0, 1, 2, 2, 0, 0, 2, 3, 2, 0, 3, 0, 0, 3, 1, 1, 2, 1, 3, 0, 0, 1, 1,
0, 3, 2, 0, 0, 1, 3, 3, 2, 2, 2, 0, 2, 1, 0, 3, 0, 2, 1, 3, 0, 2, 0, 2,
0, 0, 0, 1, 3, 2, 3, 2, 3, 1, 2, 2, 0, 1, 1, 2, 0, 2,

My Python program isn’t very pretty, and it doesn’t implement all the non-beacon message types that are needed for QSO-mode operation, but it does appear to work. I’ll make it available after I get a chance to tidy it up a bit more.