Patent ID: 7984904

Claim:
A method, comprising the steps of: forming a first wall portion to include one wall section; forming a second wall portion to include a first wall section and a second wall section, wherein the second wall section is separate from the first wall section; arranging the first wall portion in an opposing relationship with respect to the second wall portion for forming a document-conveying track for permitting conveyance of at least one documents to be moved, in series, through the document-conveying track for permitting operations to be performed on the at least one documents; utilizing the second wall section of the second wall portion as a resonator for generating a response signal including at least one of a first signal indicative of background noise associated with the at least one documents passing by the resonator and a second signal indicative of a detection of a document of the at least one documents including an attachment that passes the resonator, and mounting an accelerometer to the resonator for detecting the attachment against the resonator.