I did not see any response to this but each of the DominoEX modes does 
have an estimated SNR

For example:

DEX4  =  -14.5 dB
DEX5 =   -14
DEX8 =   -13.5
DEX11 = -12
DEX16 = -10.5
DEX22 =  -9

Add about one 1 db better SNR for using the FEC mode.

It does seem that DEX22/FEC works better than DEX11 without FEC in many 
cases even though the throughput speed is about the same. However, under 
weak signal condx, I suspect that DEX11 wihout FEC would work deeper 
into the noise. As I am finding out on many HF circuits, the ability to 
handle the vagaries of the ionosphere is often more important than the 
raw ability to handle AWGN.

I did think that MT-63 would do better than DEX11/FEC and DEX22/FEC, but 
it was much worse during the 160 meter test. Signal strengths were 
generally quite good though and QRN was not too bad considering the time 
of year here in the northern hemisphere. It will be most interesting to 
see what happens this summer with static crashes. It just seemed like 
DEX was able to handle static crashes better than other non-ARQ modes.

73,

Rick, KV9U


DuBose Walt Civ AETC CONS/LGCA wrote:

>                                       Coding  Coding
>Mode           Baud     Speed  Correction      Convolution Interleaving SNR 
>(in dB) Bandwidth
>DominoEx11     10.766  77 WPM  No              No              Not Stated      
>Not Stated       194 Hz
>DominoEx22     21.533 154 WPM  No              No              Not Stated      
>Not Stated       388 Hz
>MT63-1K        10       100 WPM        No              No              Yes     
>        -5               1000 Hz
>
>Perhaps the bandwidth of MT63 and its SNR threshold may have been the 
>difference.  But I don't know what the SNR threshold of DEx11 and DEx22 are.  
>Also, they are different types of modulations.
>
>Walt/K5YFW
>
>
>  
>

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