[Elecraft] K3 AM vs FM filter

[Ron D'Eau Claire]

For what it's worth, I'm rather astonished by the audio quality of the K3
when receiving AM in "SSB" mode. No typical "SSB sound" at all, and the
tuning allows getting on frequency within a couple of Hz, in the worst case,
so audio frequencies are very accurately reproduced. 

Using an external speaker, I've switched between the K3 with the 6 kHz
filter in SSB mode and another good-quality conventional AM receiver and
neither I or visitors can tell whether we're listening to the K3 in SSB mode
or the AM receiver, listening to either music or voice. 

I set up my K3 doing Ref Cal using procedure 2 in CW mode, so I can hear
that I've got the K3 tuning calibrated within a Hz or less. Then it's only a
matter of dialing up (or doing direct frequency entry) for the station I
want to be perfectly tuned in. 

Ron AC7AC

-----Original Message-----

Hi Bjorn,

The 6 kHz filter "is" required for AM Transmit.  The FM filter will not
work.

The FM filter will work on RX, but will not be as good with image rejection
as the 6 kHz filter.

I would suggest starting with just the 6 kHz filter.  Then if you feel like
you want/need the FM filter for AM receive, go for it.

73
Greg
AB7R


-----Original Message-----

Hi gang,

As I understand it the FM filter would be best for AM BC with its wider
bandwidth. Not perfect, but certainly better than the "AM filter" that I
guess is aimed towards voice AM communications.

Has anyone tested the FM filter for AM broadcast reception? If so, what is
your comments and advice? Is it suitable for this purpose, or are there a
better solutions out there.

Regarding AM voice operation, I do one AM contest per year. I guess it would
be possible to use the FM filter also for AM TX and restrict the bandwidth
on a DSP/audio level, or is this a bad idea?


73 de Björn /SM0MDG