10 July, 2021

Coordinated WSPR band hopping with the QRPLabs U3S

There is a recommended sequence for multi-band transmission on WSPR. It is given in the K1JT WSPR documentation. If enough receivers follow this sequence, then presumably letting WSPR transmissions also follow it, will increase the chance of detection. 

The recommended band hopping sequence cycles through 10 bands over a 20 minute period according to this table:

Band (m)   160  80  60  40  30  20  17  15  12  10
UTC Minute  00  02  04  06  08  10  12  14  16  18
            20  22  24  26  28  30  32  34  36  38
            40  42  44  46  48  50  52  54  56  58

The multi-band U3S is capable of adhering to such a sequence. There are however three considerations that need to be taken into account.