[Elecraft] DSP and MDS figures

[Ron ZL1TW]

Hi,
      Just as a matter of interest, I tried various settings on the K2 to 
see what gave me the best MDS figures , and was quite surprised at the result.
I set the K2 to "AGC OFF"  , XFIL of 800hz, in CW mode, pre-amp on,and 
tuned the K2 into the XG1's signal using the "Spot" function to make sure I 
was peaked at the top of my filter's passband.
Test one with the DSP filter set to BYPASS showed a MDS of -141.92 dBm
Test two with the DSP set at 0 gain and switched on but no DSP filter set, 
the MDS was -138 dBm
Test three with the DSP set to CF2 the MDS was -139 dbm (XFIL still 800hz)
Test four with the DSP set to CF4 was -140.4 dBm.  (XFIL still 800hz)
As one might expect, if I switched the NR in on the DSP filter the MDS went 
to -148.4 dBm
I also found that increasing the gain of the DSP filter made the MDS worse.
So.....to summarise, the K2 with no DSP filter is doing pretty well. I 
would have though the MDS figures would have been better with the DSP 
filters in, as a Spectrogram plot shows the noise floor substantially lower 
when they are used on any one XFIL.
I did expect the "Noise Reduction" setting to have the best MDS, but quite 
frankly I don't like using it in practice....especially on real weak 
signals as I reckon it "chops" the signal up and makes it even harder to 
hear! Perhaps I am not using it correctly, but quite frankly I would be 
quite happy to go back to a KAF2 ......Entirely my opinion...YMMV.
I wonder if anyone else has done a similar test?? Quite a natty little 
gadget this XG1.....
73......Ron ZL1TW
K2/100 #2204