Amateur Radio: K3RLL
- WSPR -

 The latest facet of this multi-faceted hobby that has caught my interest is W.S.P.R., or Weak Signal Propagation Reporting.

 From, "The Weak Signal Propagation Reporter Network is a group of amateur radio operators using K1JT's MEPT_JT digital mode to probe radio frequency propagation conditions using very low power (QRP/QRPp) transmissions. The software is open source, and the data collected are available to the public through this site."

 Being a long-time QRP operator, the concept behind WSPR just seemed the perfect avenue to explore some of the astounding possibilities of very low power transmission and reception of same.

Using a crystal-controlled single-band WSPR Receiver, one can easily monitor and record WSPR signals from an astounding distance. The WSPR receiver transfers received data to the microphone input of a computer that is logged into WSPRNet.Org by an authorized user. That is accomplished by simply signing up online and then logging in with one's call sign and password.

     WSPR Receiver from StellarWSPR:
Within a few minutes, the data being received and communicated to WSPRNet.Org is displayed upon the real-time world map. Data is identified on the map by user call sign. (Please see maps below).

WSPR 'stations' transmit a programmed message with their licensee's call sign and grid square in AFSK at extremely low speed. It requires just under two minutes to complete one transmission. These transmissions are precisely timed to begin at the start of the even minute, carefully calibrated to UTC or GMT.
To start out with the W5OLF transmitter as an example, the user would 'push the button' within a half-second of the start of each even minute. W5OLF also sells an auxillary timing module that, once properly sequenced, does the button pushing on time automatically.

     W5OLF 30 Meter WSPR Transmitter:

 Needless to say, I have been overwhelmed by the astounding range of not only the signals received here on my highly compromised temporary antenna system (a result of living in one of those antenna restricted communities). Even more impressive than the signals received on this antenna was the incredible range of my 1 watt WSPR transmitter.

  Okay, so what do you do with this technology 'after the new wears off', so to speak? WSPR may be the ideal antenna test tool as it leaves little doubt just where one's signal is being received and how strong it is at those locations. Signal strength is recorded, also in real-time.

 Receive results using StellarWSPR 30 Meter WSPR
     Receiver Kit on a Hamstick clone at 15 feet:

 Transmit results over 12 hours using 1 watt W5OLF
     WSPR Transmitter to a Hamstick clone at 15 feet:

 As you may have noticed in the two screen shots, the transmitter does seem to do better than the receiver, e.g., more stations seem to hear me than I seem to be able to hear. I don't know why - yet.


  WSPRNet Home Page

  WSPRNet Real-time Signal Map

  Stellar WSPR - Source for WSPR Receivers, kits or built.

   Review of W5OLF WSPR Transmitter Kit by AE5X:

   'The Radio Whisperer' by George Steber.
      Scroll down about half-way through this 'Nuts & Volts' introduction to WSPR.

   Joe Taylor's Weak Signal Communication Software page at Princeton. Scroll down to WSPR.