[1000mp] 4 kHz roofing filter

[Joe Subich, K4IK]

Bill, 

>          Joe, do you know where the 107 dB DR could have come from?
> In looking over Sherwood Engineering's list shown at Dayton, the
> maximum I see for ANY radio at ***20 kHz*** spacing is "100+ ?"
> listed for the IC-7800 (which is probably based on Icom's unqualified
> advertising claim of 110 dB).  

I don't know what test methodology W2VJN used in producing the data. 
Based on the "tone spacing," I assume he is giving IMD3 dynamic 
range.  Unfortunately, I'm still on the road and will not have 
access to my home data until the end of the week. 

George's display data included a graph of unmodified and modified 
IMD3 DR which showed a substantial improvement in the 20 to 3 KHz 
range consistent with the new front end bandwidth. 

73, 

   ... Joe, K4IK