During a period of high EME degredation I had a look at WSPR to find out what it is about.
This program turns your 'digital' ham station into a propagation monitoring/beacon station! Your radio transmits a digital signal randomly which can be received by other WSPR stations. Spots can be uploaded to a web site that presents the resulting interesting propagation data in various ways ... tabular (searchable in different ways) or in a map display form.
As the computer interface for my IC-706MK2G works on both HF and VHF, it was a simple matter to get this "new toy" on the air and try it out.
Decoded signals in WSPR received at ET3AA between 18:49z and 19:27z on 22 April 2008.
The "initial release" version of the WSPR program and information are available on the Joe Taylor K1JT web site, but here are a few tips that may make setting up easier...
1. To get started, set your radio's frequency to the default "Dial freq: 10.1387" already on the WSPR screen ... assuming you have a suitable 30M antenna! For your information, I am just using an inverted-vee dipole hanging at 20 ft above ground level from an Acacia tree in the garden. My WSPR signal has been received over 12,000km away!!
2. In the Quick Start Guide at step 8 I had trouble with an error message when setting the "TX freq:" manually (my error!) It is less confusing and very simple to follow the text in the brackets to set your "TX freq:"
3. After clicking on "Rx" you have to wait patiently for "something to happen". The program starts recording at the beginning of the next even minute ... and takes a further 2 minutes to display anything, so it could be 3 to 4 minutes before you see the first results.
4. Take note of the requirement for your computer clock to be set accurately. I do not have Internet on my "radio" computer, so I set it's clock time manually off a GPS. The particular laptop I use holds steady enough time calibration over two or more days to easily keep within the + or - 1 second recommended for WSPR. After decoding a few stations, I note the DT of their transmissions and adjust my computer's time using the "DSec" box to get DT near to 0. Of course, if you do have an Internet connection on your "radio" computer, then your computer's time can be syncronised directly from there.
5. Clicking on 20%, 25% or 33% will set your station to transmit periodically and send beacon information to other stations who may be "listening". The transmit period is 2 minutes of continuous RF, so it is very wise to keep the transmitter power setting low! Most stations have set their power output control set to transmit just 1 watt of RF output ... equivalent to the 30dBm default in the "Settings" menu. That is ample transmitter power as the WSPR software detects and decodes signals way below the noise and audiable levels.
6. To make the most of "the WSPR system" it would be nice to use the "Upload Spots" facility to send the decoded information directly from my "radio" computer to the WSPRnet web site, but I don't have a connection in the shack ... no, not even for JT65 EME operation. (Dispite the uninformed rantings from some, an Internet connection is completely unnecessary for WSJT and JT65 EME operation!) ... so I didn't select this function, but I did manually upload the spots later into the database at the WSPRnet web site via the "Spot Database" link.
The map form of propagation reports showing a
1 hour period on 30M from 23:00z on 23 April 2008.
To enhance WSPRing on other bands, here are the suggested dial requencies:
1.8086
3.5926
7.0746
10.1387
14.0956
18.1046
21.0946
24.9246
28.1246
50.2930
Your Tx freq will be in the range +1400 to +1600Hz above the dial frequency depending on the "Tx freq:" setting in WSPR.
Update : 30 April 2008
To enhance my own WSPRing experience I have moved the station from the home location at KJ98jx to the work location at KJ99ja ... this will also allow instant spot uploads via the ADSL connection there and 24 hour operation. The antenna (inverted vee dipole) is now at the top of a 6 floor building with clear views in most directions. Looking back at old spots, the higher antenna at the new location appears to be 10dB better! I have also replaced the IC-706MK2g with a commercial Codan 9360 transceiver that has the PA fan kit fitted ... this combination means I can run higher power without burning anything up!
I look forward to the resulting spots!
Update : 02 May 2008
Corrected the frequency error in the Codan transceiver.
My RX spots should be close to the right frequency now.
I am transmitting with my WSPR "TX freq:" on 10.140140
Update : Nov 2008
QRV from ZL for a change! I'm operating from rented
accomodation close to our "retirement" QTH at RF64vs.
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