It seems I cannot do this with tr

[Phil Howard KA9WGN]

What I want to do is to translate ALL characters EXCEPT the ones I can
provide a list of, to some other character (all will be to the same one).
For instance if my character list has '[A-Z]' and the other character
is '.', then my output would have only A-Z and (probably) lots of dots.
I could use "tr" if it was practical to generate the list of ASCII
characters NOT in the list I have, but I am just wondering if a simpler
solution exists.  If not, I'll write a C program.
-- 
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/ Phil Howard -- KA9WGN -- phil at ux1.cso.uiuc.edu   |  Guns don't aim guns at  \
\ Lietuva laisva -- Brivu Latviju -- Eesti vabaks  |  people; CRIMINALS do!!  /
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