WSPR 2.20: Frequency Hopping
- You may have noticed that a few of us have been playing with a version
of WSPR that does automatic "frequency hopping" from band to band. For
this we owe a big vote of thanks to Sivan Toledo, 4X6IZ, who wrote most
of the initial frequency-hoppping code.
If you would like to try WSPR with frequency hopping, a beta-release of
WSPR 2.20 is now available at
Select "Frequency Hopping" on the Seup menu, and you'll get a screen
allowing you to select any desired mix of bands and Tx fractions. Then
check "Frequency Hop" in the main window, and WSPR will start its normal
2-minute sequences, switching bands randomly after each one.
Depending on your station and antenna setup, you might need to
accomplish other switching besides re-tuning your radio. To make this
possible in an automated way, whenever WSPR executes a successful
band-change command to a CAT-controlled radio, it looks for a file named
"user_hardware.bat", "user_hardware.exe", or "user_hardware" in the
working directory. If one of these is found, WSPR tries to execute the
where nnn is the band-designation wavelength in meters.
You will need to write your own program, script, or batch file to do the
necessary switching at your station. I wrote a very simple Python
program for this purpose. One of my antennas is an "all band" dipole
fed with open-wire line through an automatic antenna tuner. Others
include a 160m vertical and a tri-band trap dipole. The antennas are
selected automatically, by band; and when a transmission on a new band
starts on the all-band diploe, the tuner adjusts itself during the first
few seconds of the transmission.
Many desirable features for a frequency-hopping WSPR are not yet
implemented. It seems best to get some feedback from experienced users
before the following things (and surely many others) are added:
1. Save/Restore of one or more band-hopping setups.
2. Transmission of a short "tune-up" carrier, to be used by automatic
antenna tuners, just before starting a normal 2-minute sequence.
3. Possible changes in the algorithms that determine when to change
bands and when to transmit. (At present, both are "purely random".)
As always, comments and suggestions are welcome!
-- 73, Joe, K1JT
For the WSJT/MAP65/WSPR Development Team