[Elecraft] K2 DSP summary

[Lyle Johnson]

Hello Rich!

> At first, I thought you either used XFIL or AFIL. One or the
> other... but this does not seem to be the case.

The signal passes through the crystal filter (XFIL), is amplified by the IF
amplifier, then is converted to audio and passes through AFIL on its way to
your ears.

The K2 MCU doesn't provide XFIL info to the KDSP2, so it was not possible to
link them together.  Thus, you must do this manually.

Typically, you set the XFIL and AFIL bandwidths to similar levels.  You
often might want to narrow the AFIL more than XFIL, but it rarely makes
sense to have the AFIL wider than XFIL.

Keep in mind that the AGC is controlled by what passes through the XFIL;
AFIL has no effect on which signals activate the AGC.

Finally, some operators prefer to leave everything as wide as possible until
QRM/QRN make it hard to do so.  For CW use, selecting wide XFIL, AFIL set to
LPASS (the default for AFIL 0), and then activating the denoiser, makes
monitoring pretty easy, with signals seeming to just pop out of a very quiet
background.

73,

Lyle KK7P