how to substitute a no printable character by a string in a text file

From: ROBIN Jean-Marie \(EURIWARE S.A.\) <"ROBIN>
Date: Fri, 09 Mar 2001 17:00:38 +0100

Hello Managers,

I want to substitute in a file a no printable character by a
multi-characterstring, as something like that:

sed s/\octal_code/"my_string"/g myfile

sed does not like this syntax and I can't use tr, because my string is
multi-character...
Any suggestions?

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Received on Fri Mar 09 2001 - 16:02:07 NZDT