Figure 5-11.The LMS-11 Net Display in PU History Mode.

Figure 5-10.The LMS-11 Net Display in Summarize Mode.

Figure 5-12.The LMS-11 PU Display mode.

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Figure 5-11.—The LMS-11 Net Display in PU History Mode. SIG PWR. —The total signal strength of the 16 tones, measured in dBm. A value of -51 indicates that no signal was received. SNR. —The signal-to-noise ratio, as measured in dB. The SNR is calculated as the average power in the data tones divided by the average power in the noise tones. The LMS-11 can measure a SNR of near 34 dB. A number preface by the greater than symbol “>” indicates that the average power in the noise tones was below the measurable threshold. In this case, the number represents the data tone signal strength only. An SNR value of 30 or higher is considered excellent. An SNR value of less than 10 is unusable. FRAME CNT. —A count of all data frames received over the specified number of cycles. Data frames include the phase reference frame and control code frames in each message. A value that is followed by a “?” and color-coded yellow is displayed if the frame count of a picket station average is less than or equal to six frames. The two start code frames, the phase reference frame, the crypto frame, and the two stop code frames would account for the six frames. Therefore, if a picket unit transmits six or less frames, no actual message data is being received and may indicate a problem with the computer or DTS of the unit. A yellow color-coded value followed by the “?” is added for an NCS when the number of frames is equal to or less than eight. The two additional frames account for the next station address at the end of an NCS report. PERCENTAGE THROUGH. —The %THRU column is a number that indicates the percentage of message data that is received error-free. the percentage is found by comparing the number of error-free message data frames with the total number of message data frames received. CF. —This is a percentage of control code failures. A PU with strong signals that never misses a call will have a 0 % code failure. A PU that never answers, such as a dummy PU, will have a 100 % code failure. 5 - 1 4

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