vrijdag 7 februari 2014

WSPR with 200 mW down to 1 mW by Hajo DL1SDZ

More and more operators discover the use of very low power with WSPR.
On his blog Hajo DL1SDZ reports of spots made with 200 mW down to 1 mW.
He reduced the power from day to day, as shown in the second analysis.

The first analysis shows the calculated lowest possible power.
The lowest p[ossible power is calculated from the power sent and the SNR.
The lower the lowest possible power, the better the propagation.

Click to enlarge
The analysis below shows electrical field strength.
In this calculation the distance is also included.
The lower the field strength, the better the propagation.

Click to enlarge
In the analysis all spot over 400 km and more are in cluded.
Thanks Hajo, for the interesting experiment.

4 opmerkingen:

  1. Hello Bert, I set a ling from my article to your analyses. But I think that there is one misunderstanding: My last transmission was done with 0.5 mW or -3 dBm. But I could not correct the report in the Ultimate 3. The lowest number I could type in was 0 dBm. So I gave a false report to ON7KO. Sorry - I couldn't do better. Or did I misread the numbers?

    1. Hello Hajo, the lowest power in the WSPR data is 1mW or 0 dBm, so you choose the right value for your power of 0.5 milliwatt. 73, Bert

  2. Sorry for the inconvenience. Everything is OK! I have to read more careful next time. Thanks again and all the best.


  3. Bert, if you speak a little bit German or with the help of Google Translate, here is an ongoing discussion about Milliwatting: http://www.qrpforum.de/index.php?page=Thread&threadID=9197