[Elecraft] Comparison: K3 and SDR 5000A

[John A. McCabe]

Hi John,

Although I do not have a 5000, I do have a SDR-1000. Elecraft and Flex 
are both Good companies that produce great radios. However, I believe 
one major difference between the K3 and the Flex 5000 will be in wider 
space dynamic range. The close-in 2Khz dynamic range for the 5000 I 
believe was measured by Rob Sherwood at 96db which is a good number. 
But  the 5000 does not have roofing filters, so if I am not mistaken, 
the 96db IMD dynamic range will the same at 2Khz, 5Khz, 10Khz, 20Khz, 
and beyond,  as it is with most sound card based SDR's.  To me a 96db 
Dynamic range beyond 20Khz is not good. I believe that a 96DB dynamic 
range is around 40-45db over S9, so if my calculations are correct, IMD 
could be a problem from a 45db over S9 signal 20Khz or more away. That 
is one of the reason's why I chose the K3 over the 5000. The K3's close 
in numbers will be around the same is the 5000, but the wider spaced 
measurements I expect to be much better then the Flex-5000.


John, KD8K