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WSPR - Weak Signal Propagation Report

Feb 17, 2006
Lancer 27PS MCB Camp Pendleton KF6BL
Hi guys. I see there has been a lack of activity here so time to make a little noise.

I like working digital mode, in particular JT65A. It is amazing how one can reach out to far places with little power. Mostly I am using 20w into my wire antenna. But the disadvantage is know where your signal is landing. Or who would be able to hear you if they were listening.

Enter WSPR, the Weak Signal Propagation Reporting system. This is a software program that will use your rig to send out short messages every 10 minutes. The message is very simple; call grid power. In my case it would be KF6BL DM13 37. The 37 is how much power I am using in dBm. 37 dBm is equal to 5 watts. So I have set my radio to transmit at 5 watts.

At the WSPR website, there is a map that one can use to view how the bands are working. Again, this is based on about 5 watts (more or less for some stations). So you can look at your QTH and see how the bands are opening and to where.

My antenna is a wire about 36' long oriented at about 20° true. I have noticed that I am hearing signals better at E and NE, also W and NW. I do hear some signal to the south but that is only when those guys are there. LOL

Anyway, what does this have to do with sailing and SSB use? If one runs the program while afloat, one can see how the antenna is propagating received signals and what strength. Might not mean anything or be that important to all, but maybe one can determine the boat direction is either beneficial to or puts you at a disadvantage signal wise.

So that's my report for now.
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Likes: Rick D
Feb 17, 2006
Lancer 27PS MCB Camp Pendleton KF6BL
Here is the map showing the stations that can hear my 5w signal on 40m.

Nov 6, 2006
Hunter 34 Mandeville Louisiana
Pretty cool ! My dad used to do similar by plotting the QSL cards .. Curious if the digital query signal is "CQ" ? ;)
Feb 17, 2006
Lancer 27PS MCB Camp Pendleton KF6BL
Yeah, one could call it a field strength meter of sorts. Best it does is tell you where you signals are going. And if you have any issues or reception. I found last night that I am being heard better than I can hear. So I might have an issue with my received capabilities like maybe a poor counterpoise system.
Sep 25, 2008
Alden 50 Sarasota, Florida
Just compared some signal levels today using this method and then turned the boat around in the slip to compare. My boat has about 4dB of forward gain. Similar to a 2element yagi :)

Although over an elapsed time of about one hour during which conditions likely changed...
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Likes: Brian D