Craig's filters are very good, with good ultimate rejection, but Mechanical
Filters have an ultimate rejection of 120dB. True, this figure is better
than the dynamic range of most receivers, and also true, you have to have
very good shielding/ground in your PC board layout scheme in order to obtain
this 120dB figure.
100dB ultimate rejection is a good figure to shoot for. I have spoken to
Craig a few times.....he is a very good designer.

Pete

"Guy Atkins" wrote in message
...
Craig at Kiwa Electronics seems to have figured out how to make quality
filter modules from series-cascaded Murata ceramics. He uses low noise
buffer amps as part of the package in Kiwa's Standard and Premium Filter
Modules (PFMs). The latter are particularly good, with ultimate rejection
figures exceeding Collins mechanical filters and better shape factors than
quality crystal filters... and at a very good price for the performance.

I've used a number of PFMs over the years in various receivers, and
they've performed excellently for DXing and program listening.

http://www.kiwa.com/kiwa455.html

Guy Atkins
Puyallup, WA USA


"Arthur Pozner" wrote in message
...
Murata filters are not known for good shape factor(6db//60db) . When
stacked in series losses mount rapidly. And they seem to have a lot
more noise when compared to crystal or mechanical IF filters. Have you
tried to build a crystal ladder filter? Very effective and MUCH cheaper
than any other IF badpass filter ,and Inrad is not the costliest-
KVG,Collins etc.may set one back many hundreds of dollars...