NCJ Number
132189
Journal
Journal of Forensic Identification Volume: 41 Issue: 3 Dated: (May/June 1991) Pages: 179-189
Date Published
1991
Length
11 pages
Annotation
The serial time code data collected on the reels of logging-type recorder systems proves important to the forensic examiner when examining a tape for alterations or possible loss of information from a breakage.
Abstract
This discussion explains time waveform analysis in authenticity examinations of the serial time code information and describes the specific data placed on the logging systems commonly used by police departments and other sources of investigative tapes. As it is inherently difficult to modify a logging tape, an authenticity examiner often is trying to determine if there has been an alteration, or in the case of a broken tape, whether any information has been lost. Time waveform displays provide a visual pattern of the pulse data of the codes. These then can be deciphered into binary digits which directly represent time of day and other information. 5 figures, 1 table, and 5 references