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3. COMPLIANCE TO TESTING METHODOLOGY <br />In most cases, the test points chosen were at the end of the longest amplifier <br />cascade depicting the expected worst-case performance in that portion of the <br />distribution system. With the rebuild, Time Warner has redesigned the cable <br />plant to a hybrid fiber / coax system, which eliminates long cascades of amplifiers <br />as well as other technical related problems along with it. The longest cascade in <br />the new rebuilt system is six. <br />The 100 -foot drop was connected to the chosen tap or device and the following <br />measures were made: <br />1. Picture/Audio Analysis - Each channel is viewed and any imperfections <br />noted. Mr. Whitfield made observations with confirmation by a Time <br />Warner representative. Observations of less than excellent pictures are <br />recorded. Problems noted at Headend are addressed and corrected by <br />the Headend engineer typically at time of detection. Corrections are <br />usually made in the presence of Mr. Whitfield and verified by him. <br />2. Carrier -to -Noise - Baseband signal to noise in dB is measured non - <br />disruptively by the system analyzer. The results are logged and stored in <br />the test device memory. This measures the relative "snow" in a picture. <br />3. Third Order Distortion - Composite Triple Beat - This is ratio, expressed in <br />dB of the peak RF level of the signal to the average power cluster of <br />distortion products centered around the carrier. Testing methodology is <br />performed by momentarily dropping the video carrier on selected channels <br />while monitoring a system analyzer for distortion in the selected channel <br />spectrum. This measurement identifies beats in a picture, which may or <br />not be visible in subjective viewing. <br />4. Low Frequency Distortion (Hum) - This measures the amount of 60 or 120 <br />cycle interference on an unmodulated channel. The system analyzer also <br />performs this measurement without disrupting the channel. The results <br />were logged and stored in the test device memory. <br />5. RF Level Measurements - The level readings of all aural carrier and visual <br />carrier were measured, automatically logged by the test equipment and <br />later printed out on hard copy. (The system does not allow any <br />manipulation of the data once taken.) <br />7. Visual Carrier Delta - The printout calculates the channel with the highest <br />video level compared to the channel with the lowest video level and the <br />"Delta Difference" or "Peak -to -Valley" is reported. <br />Communications Support Group, VP RPT2007.001 Page 5 <br />