WSPR 2.21 and Frequency Hopping

A beta release of WSPR 2.21 r2286 has been posted at:

Windows:
http://www.physics.princeton.edu/pulsar/K1JT/WSPR2.21_r2286.EXE

Linux:
http://www.physics.princeton.edu/pulsar/K1JT/wspr_2.21r2286_i386.deb

As in r2283, this version includes a "Coordinated hopping" mode in which the selected band is determined by the starting UTC minute of a Tx/Rx interval:

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

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

In r2286 the algorithm choosing whether to Rx or Tx guarantees at least one transmission on each active band every two hours. If all ten bands are active there can be up to three transmissions on a band in a two hour period. These choices will tend to maximize the number of potential spots on all bands, by all frequency-hopping stations.

It's not hard to discover the identities of some stations who've been doing "coordinated hopping" over the past few days. I have been using all 10 bands (Rx only on 60 m). Here are a few who have spotted K1JT many times on different bands during the past 24 hours:

AK4DW (932 km, 53 spots): 160 80 40 30 20 17 15
EA1FAQ (5703 km, 59 spots): 80 40 30 20 17 15
G4KLA (5485 km, 29 spots): 80 40 30 20
G8JNJ (5480 km, 23 spots): 80 40 30 15
KC6KGE (3942 km, 15 spots): 80 40 30 20
KE7A (2160 km, 53 spots): 160 80 40 30 20 17 15
N4AU (1342 km, 71 spots): 160 80 40 30 20 17 15 12
W3PM (1240 km, 64 spots): 160 80 40 30 20 17 15

It's fascinating to watch the daily changes in ionization, causing each band to open at an appropriate time.

-- 73, Joe, K1JT