In the series ‘what is WSPR?’ I did some reading last night. If I understand it correctly WSPR is a little computer program made by K1JT that is used to detect propagation on the amateur bands. It is using a very weak digital signal which is produced by your sound card in your computer and send out thrue your transmitter. Your computer also listens on the frequency to spot other ‘WSPR beacons’ and tells the central WSPR server via internet of the status.

WSPR means: Weak Signal Propagation Reporter. The program uses your sound card in QRSS mode and scans a 200Hz band for a signal of 6Hz wide with a baud rate of 1,46 Baud. 4-FSK modulation. Apparently there is 1 tone from your sound card. The nice thing about it is that you’re be able using mini wattage (a few hundred mW) to make big distances. A transmitting cycle lasts 110 seconds and there is minimal information packed.
The signals are received and decoded and sent to a central server and put on a map and a list.

So far the theory, in part 2 my search for a mac version of the program (as my faithful readers know, I’m a real Mac-lover).

Links: original instructions from K1JT
The program
The website (of the central server)

OZ1PIF manual to WSPR