Wednesday, October 7, 2020

Operating mode comparisation chart including FST4

 DB6LL Hartmut made a very nice comparisation chart which he published on facebook. I got permission to publish it on this blog to inform even more HAMs. Thank you Hartmut!

I still have to try this new digimode. I think it is interesting to actually see digimodes developed that can compete with the sensivity of WSPR. If you look at my previous post what is reachable with simple equipment 5W and a small antenna, with FST4 you can actually make a real QSO worldwide.

7-Feb-2021 Updated chart after discovering an error 


  1. Very usefull Bas, although I think that differences are even far more if there is much QRM during reception. On the other hand, one must also take the time needed to reliable transmit and receive the information in consideration, I think!
    73 de OE3FVU / PE0WGA

    1. You know Franz,the difference between QRO and QRP is.....time. 73, Bas

  2. I'm hoping Hans G0UPL will write new firmware for FST4W (beacon mode) for his Ultimate 3S transmitters. Although said to be for 630 and 2200 meters, there is now activity in this mode on 80 meters.

    73 - John

  3. Power to dB is not correct. There are several errors.. 20dB difference is 100x in table 3 and 4. A nice theoretical table in practice it will be different 😀 73! John pa5ms

  4. This gets my 'post of the year' award! Very interesting. I'm bound to try FST, but a two-way WSPR 'exchange' is indeed potentially much faster and so far as anything can be, a valid 'real' qso. Looks like I will have to spend more time at the beach...

  5. Afterthought: this seems already to be splitting the population of WSPR users into two camps. I suspect that, unless we're careful, we'll end up with a fragmented 'beacon' population that ultimately reduces the number of people active on any given mode, and a reduction in the dataset. Also, if the 60s TX population can't decode the other periods of TX with FST, then the population will be really very fragmented.

    I do wish this WSJT team would consult with the wider community, rather than just launch things to the world.

  6. You could consider to write this on your own blog? You have a good point. Something that is already featured in JS8Call. You can choose several time based modes like FTS4, but everyone can always RX decode it. However to transmit a specific mode you have to choose. 73, Bas


Thanks for your comment. Bedankt voor je reactie. 73, Bas