[Elecraft] K-3 Roofing filter comment

[Dave Hachadorian]

> The DSP forms the
>ultimate filter, and does have nearly vertical slope.

I think one of the Elecraft folks stated on the reflector that 
the -60dB BW of the DSP is (-6dB BW + 300Hz).

So at DSP BW = 2800 Hz,
BW60 = 3100 Hz.
Equivalent shape factor would be 3100/2800 = 1.1
That's pretty doggone steep.
Any reasonable amplitude signal (not triggering hardware AGC) 
over 1550 Hz off center would be down 60 dB.

I think I've got that straight. Comments welcome.

Dave Hachadorian, K6LL
Big Bear Lake, CA











































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