Abstract: A system is disclosed for deterring theft of portable electronic equipment that operates in accordance with an industry standard known as EIA-232-D. A theft deterrent unit monitors signal current transmitted between interconnected electronic units. When one or more of the interconnected electronic units is disconnected, the theft deterrent unit detects the cessation of signal current and activates an alarm. The alarm may be used to generate a local alarm such as, for example, an audible alarm, and the alarm signal may be transmitted to a central alarm system for further processing.

Abstract: Apparatus generates synchronized timing for both the up and down links of a transmission path such as a telephone line, which telephone line carries bipolar data. The apparatus operates to detect a Start of Frame signal which signal constitutes a known violation in the bipolar data. This Start of Frame signal is applied to a series of dividers and decoders which operate in conjunction with an oscillator to produce a series of timing signals related to the Start of Frame signal. A selected one of the timing signals is utilized to synchronize the up link apparatus to the down link apparatus. In this manner the counter circuitry which is employed in both the down link side and the up link side is used to accumulate any timing difference between the data source and the data receiver. After a number of bit periods have passed, the timing signals generated will move with respect to a data bit, depending on whether the clock at the transmitting end is slower or faster than the clock at the receiving end.

Abstract: Method for use in developing, testing, debugging, and/or troubleshooting a call progress monitoring (CPM) detection system which is utilized, for example, by a voice messaging system (VMS). One embodiment of the present invention which is utilized in conjunction with a VMS includes the steps of: (a) monitoring at least one voice channel of the VMS to obtain CPM tones and having a CPM Detection system associated with the VMS perform an analysis of the CPM tones, the output of which analysis is referred to as CPM Trace Variables; (b) storing the CPM tones and the CPM Trace Variables for the at least one voice channel, which stored CPM tones and CPM Trace Variables are referred to as a CPM Trace file; (c) obtaining a first voice channel; and (d) feeding the voice portion of the CPM Trace file to a second voice channel for playing it to the first voice channel.