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PROCEDURE <br />Pre -Flyover <br />Determine system boundaries and import into DeLorme mapping software to <br />form a cable plant boundary polygon. <br />The cable plant polygon is used with the CLI crew's on -board CLI survey <br />software. <br />Determine channel and time for testing, using a negative offset modulated carrier <br />between 108 and 140 MHz. Choose a negative offset frequency from common <br />video for channel to be tested. <br />Perform CLI receiver calibration using Lindsay ground calibration antenna with a <br />modulated test signal at 10 uV/m at 1476 feet using a HP Signal Generator <br />8647A-1 E5. <br />Use the following formulas to establish signal generator input level for aerial <br />calibration: <br />Calibration <br />Establish signal generator input levels that will be used to calibrate Sniffer Sleuth <br />receiver based on a 10 pV/m leak at 1500 feet. <br />a. Convert uWm to dB: <br />133.2375 Mhz Frequency(Mhz) <br />10 uV/m uV/m WE' <br />-48.81 dB (20*log(E)) - (20*log(20.7*Frequency)) <br />b. Determine Free Space Loss at 450 meters: <br />133.2375 Mhz Frequency(Mhz) <br />1476.38 Feet (450meters) Distance(Feet) <br />68.01 dB 20*log(Frequency) + log(Distance) - 37.87 <br />C. Determine Signal Level input for calibration expressed in millivolts: <br />-48.81 dB 10uV/m level expressed dBmv for test frequency <br />Add 68.01 dB Free Space Loss <br />Equals 19.19 dB Total <br />dB to mV 9.11 my 10^((dB)/20) <br />Test signal level input of generator with signal level meter to insure accuracy. <br />Perform aerial calibration runs recording highest reading in uV/m to obtain a <br />calibration factor to be used in post CLI process. Highest recorded number <br />during calibration runs for this specific test was 10 uV/m. <br />Apply correction factor: <br />Frequencies below 108: <br />Frequencies above 137: <br />(Data Sample) + 20 * log( f/108 ) <br />(Data Sample) + 20 * log( f1137 ) <br />The Flyover Company, LLC - 3 - <br />