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Headend Subscriber Signal Tap Tests Levels of low frequency distortion Levels of composite triple beat Levels of video and audio Separation between video carrier and noise Picture Quality Visible distortion Picture clarity System Powering Auxiliary Headend Powering Power plant condition 3. COMPLIANCE TO TESTING METHODOLOGY In most cases, the test points chosen were at the end of the longest amplifier cascade depicting the expected worst-case performance in that portion of the distribution system. With the rebuild, Time Warner has redesigned the cable plant to a hybrid fiber / coax system, which eliminates long cascades of amplifiers as well as other technical related problems along with it. The longest cascade in the new rebuilt system is six. The 100 -foot drop was connected to the chosen tap or device and the following measures were made: 1. Picture/Audio Analysis - Each channel is viewed and any imperfections noted. Mr. Whitfield made observations with confirmation by a Time Warner representative. Observations of less than excellent pictures are recorded. Problems noted at Headend are addressed and corrected by the Headend engineer typically at time of detection. Corrections are usually made in the presence of Mr. Whitfield and verified by him. 2. Carrier -to -Noise - Baseband signal to noise in dB is measured non - disruptively by the system analyzer. The results are logged and stored in the test device memory. This measures the relative "snow" in a picture. 3. Third Order Distortion - Composite Triple Beat - This is ratio, expressed in dB of the peak RF level of the signal to the average power cluster of distortion products centered around the carrier. Testing methodology is performed by momentarily dropping the video carrier on selected channels while monitoring a system analyzer for distortion in the selected channel Communications Support Group, VP RPT2008.001 Page 3