5.Activate the unit following the “Activating
Optimizing Signal Strength
For robust operation, signal strength received from the antenna must be optimized. Optimum alignment of the antenna may be achieved using the signal strength menu. Press and hold the power button for 4 seconds, a display similar to below will appear.
CN1 CN2 TBER
9.0 8.5 12%
CN1 and CN2 indicate the carrier to noise ratio of the satellite signal received from the two XM satellites positioned in the southern sky over the equator. The higher the number the better, and both numbers should be 10 or greater for good margin, but not less than 7.0.
TBER is the percentage of bit errors received from a terrestrial repeater, if there is one. Acceptable values for this number may be anywhere from 0% if a repeater is nearby, to 100% if only the satellite signals are available – lower is better. The audio mute threshold for the terrestrial signal is approximately 6% bit error rate.
Position and rotate the antenna for the optimum balance (highest readings) for CN1 and CN2. Note that CN1 measures signal received from the satellite in the Eastern sky, CN2 signal received from the satellite in the Western sky. Obstructions such as trees or tall buildings may interfere with reception of one or more satellite signals and require that the antenna be repositioned.