1. Effect of μ-Law Companding on the Performance of a PCM System
2. Effect of A-Low Companding on the Performance of a PCM System
1. Set up the modules as shown in Figure 3-56. Before inserting the Lowpass Audio Filter into the Enclosure / Supply Regulator, place the COUPLING switch (mounted on the circuit board) in the AC position. Make sure that all OUTPUT LEVEL and GAIN controls are placed in their respective MIN and CAL positions. and power up the equipment.
8. Adjust the Channal A OUTPUT LEVEL of the Dual Function Generator untill the True RMS Voltmeter / Power Meter reads 0.650 V. The oscilloscope display should now resemble Figure 3-59.
9. Connect the True RMS Volmeter / Power Meter to the BNC T-connector on the AUDIO OUTPUT of the Lowpass Audio Filter. The reading on the True RMS Voltmeter / Power Meter is the total output voltage. Record this reading in the corresponding row of the TOTAL OUTPUT VOLTAGE V0 column of Table 3-5.
10. Connect the True RMS Voltmeter / Power Meter to the NOTCH FILTER OUTPUT on the Nosie Measurement Filters. Record the reading on the True RMS Voltmeter / Power Meter in the OUTPUT NOISE VOLTAGE Vn column of Table 3-5.