[Elecraft] APF effectiveness...

[Chuck Guenther]

I find the APF to be very effective when preceded by a relatively wider 
filter
as suggested by K9ZTV, and offsetting the receive a little as mentioned 
by W6OPO.

I generally use the 250 Hz crystal filter, followed by a DSP bandwidth 
between
200-300 Hz.  I use a macro to turn on APF and FINE and offset the RIT by 
20 Hz, then
I tweak the APF shift and/or the RIT manually to peak the received signal.

The purpose of the offset is to shift the signal frequency away from the 
ringing
frequency.  This works best for me at pitch settings near the low end of 
the K3's
range.

73,
Chuck Guenther  NI0C



W6OPO wrote:
"

I have had input from two Elecraft support fellows one of which was
helpful.  That being move the receiver off frequency (RIT) about 10Hz
then adjust the APF center frequency to match.  Some help - yes."


K9ZTV wrote:
"
I've found that using the APF with the 400 filter (or wider) dialed-in
provides less ringing than using APF with the 50 filter (DSP) dialed-in."