[VHFcontesting] IF filter selection

[Joel N. Weber II]

The club I'm involved in (w1xm) is looking into adding filters to our
IC-746, which has never had any of the optional filters installed.  It
has been the rig we use for 6m in the VHF contests, and we also have
used it for HF for Field Day.  We do primarily SSB operation, as most
members of the club aren't terribly proficient at CW operation, but
there is one operator who frequently does CW, so we want to have
filtering that is suitable for both modes.

Which filters would be best to install?  I understand that the rig
will take up to three optional filters, some of which have a 455 khz
center frequency, and some which have a center frequency somewhere
around 9 mhz.  I don't think I've ever come across much literature
that explains in much detail why one would prefer one center frequency
over the other, nor am I terribly clear on which bandwidths are best
for SSB use.

So I'm curious if the people on this list have thoughts on which
filters would be the best to get, and why.

(Another possibility that has been suggested is that perhaps replacing
that rig with an FT-920 (or perhaps some other rig) would be
worthwhile.)