Tuesday, April 29, 2008

W8TN Now WSPR'ing on HF

Have you ever wondered just how much power it takes to communicate on Ham Radio? Or, if a particular band is really open for communication? Well, Ham Radio's Nobel laureate, Joe Taylor, K1JT, has recently written a new piece of digital soundcard software for HF Propagation. It is called WSPR (pronounced "whisper") and stands for "Weak Signal Propagation Reporter." You can see a screen shot of the program running HERE.

Basically this software runs on your computer and transmits and receives over your HF (or VHF) radio. Running very low power (on the order of 1/2 to 5 watts) the program allows reception of signals at distances and times of the day that most DX'ers might think impossible for that power level.

To give it a try I downloaded the software from Joe's web site HERE, installed in on my computer and configured it by typing in my callsign, my grid, the power level I was running in dBm and the soundcard numbers for input and output. Within a few minutes I had it operational and was transmitting on 30-M at a power level of 32 dBm (less than 1.6 watts!) This was between 4 and 6 p.m. today so I was not really able to utilize any nighttime propagation. Over a period of 40-minutes here is a list of the stations I was able to copy (click on the box below to enlarge it):
Note that I was able to copy SV8CS at a distance of 5242 miles while he was running 5 watts. This took place 3 hours BEFORE my sunset. Also, here is a list of stations that were able to copy me while I was running just under 1.6 watts output power:

Best DX of stations that heard me was IV3GTH at a distance of 4612 miles. Oh, did I forget to mention that I do not have a 30-M antenna! Yep, I was using my 80-M Inverted-V as an antenna with the FT-1000MP MkV's internal tuner. Without the tuner the SWR was 4.92 : 1.

If you wonder how I was able to determine who heard me, there is a web site that allows stations to upload their logs so everyone can see who has heard them (and who else is being heard.) It even has a map that shows the paths that are open on any particular band. That web site (which has a Chat/Sked Page, Forums and other useful information) is available HERE. BTW, I was the 344th distinct callsign reported using this mode.

Tonight I plan to fire up my WSPR signal on the Monster-L and see who can hear me on Top Band with such low power. I'll add a note to this post after tonight's session.

160-M Addendum: Well, my evening on 160-M was not quite as exciting as on 30-M this afternoon but still VERY interesting. I copied F6IRF at 10-watts and he copied me at 10-W. He is in JN35au so that is 4,312 miles on Top Band with just 10-watts at each end. Later I was copied by F1US when I was transmitting at 3-watts! He is in JN04fv so that is 4,099 miles at just THREE watts! On 160-M no less! Pretty awesome if you ask me. Also, my 3-watt signal was heard by GI3HXY at 3,580 miles.

An interesting footnote is that I checked over 1,000 spots from 0245 to 0500 GMT and my 10-W contact with F6IRF was the LONGEST one reported! That is, except for one report where K4CML copied CM8RF who was running 126 watts. Not quite in the same league I'd say. Thank you Monster-L!

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