WSPR 2.20 r2283, Beta release

If you have been testing WSPR 2.2 with its frequency-hopping feature, please upgrade to revision 2283. Direct links for download are:

Windows:
http://www.physics.princeton.edu/pulsar/K1JT/WSPR2.20_r2283.EXE

Linux:
http://www.physics.princeton.edu/pulsar/K1JT/wspr_2.20r2283_i386.deb

This version has several new features:

1. A checkbox labeled "Coordinated bands" is now available at the bottom of WSPR's Frequency Hopping screen. If this box is checked, the first-choice selected band will be determined by the UTC minute at which a 2-minute sequence starts:

UTC Band
Minute (m)
----------------
00 160
02 80
04 60
06 40
08 30
10 20
12 17
14 15
16 12
18 10

20 160
22 80
... etc

The sequence of ten possible bands repeats three times each hour. If the first choice band has not been checked as an active band, a random band choice is made among those that are active.

Decision whether to receive or transmit is purely random, using the "Tx fraction" for the selected band.

If all WSPR stations using frequency hopping use the "Coordinated bands" option, a sizable group of us will move together from band to band. During any particular sequence, something like 20% of the stations (depending on their Tx fraction settings) will transmit, and the rest will receive. The average number of spots will be much larger than that if band selection is random. If a band gets too crowded -- say, if you often see more than 6-8 stations in one sequence -- you should probably reduce your Tx fraction for that band.

2. There is now an "ATU tuneup" feature. When WSPR hops to a new band, if the "Tuneup" box for that band is checked the program will transmit a carrier for 4 seconds. This should happen at about 115-119 s in the basic 120-second cycle. The idea is that automatic ATU's would tune themselves during this time. (It may turn out to be better to use a shorter tuneup interval, say 1 second, or to make the duration a user parameter. Automatic ATU's with memory need only a very short signal.)

3. Frequency-hopping parameters are saved on program exit and restored when the program is restarted. The information goes to a new file named "hopping.ini".

As usual, user feedback is encouraged!

I have been running in this mode for the past few days, and will continue doing so this week. Please give it a try, so we can have a significant number of stations moving together from band to band.

-- 73, Joe, K1JT