On Sat, 17 Mar 2007 01:25:47 -0400, **THE-RFI-EMI-GUY**
wrote:

I need to filter noisy signal with a single frequency tone falling in
the pass band 67 to 250 Hz and am looking at using a 567 PLL or an
XR-215A or the like. It appears that the bandwidth of these are quite
narrow as they are usually used as tone decoders. Any suggestions? I
want to obtain as clean a tone out as possible.

The application is to regenerate a CTCSS tone. Simplicity counts!
I used a 567 PLL many years back as a Morse Code audio filter for CW.
It worked pretty well.

John Ferrell W8CCW
"Life is easier if you learn to
plow around the stumps"