3-30Performance TestsPDH/DSn Transmitter OutputNOTE Using the balanced to unbalanced converter reduces the pulse amplitudeby a factor of 1.266. This will cause the comparison with the mask to fail.To overcome this select CHAN 1 ON and reduce the Volts/Division setting(highlighted on the softkey display). Reduced Volts/Division = highlightedvalue/1.266. The new value can be entered using the keypad8 The Oscilloscope will compare the positive pulse with the mask limits.A PASS message should appear on the Oscilloscope.NOTE It may be necessary to visibly fit the waveform to the mask by adjustingthe Oscilloscope vertical position and horizontal delay to obtain a PASSon the Mask.9 Measure the peak pulse amplitude at the mid pulse-width using theOscilloscope and verify that this is between 1.896V and 2.844V.Negative Pulse10 On the Oscilloscope, use the following key sequence to access theinverted mask.a/ SHIFT (Blue Key) DISKb/ softkeyc/ Use ENTRY/MEASURE control to highlight INV_MASKd/ softkeyLoad the Telecom Mask11 On the Oscilloscope, use the following key sequence to select and loadthe required Telecom Mask:a/ SHIFT (Blue Key) APPLICATION.b/ softkey.c/ Use ENTRY/MEASURE control to select DS1_NEW in thehighlighted MSK FILES window.d/ softkey.Compare Pulse with Mask12 On the Oscilloscope, use the following key sequence to compare thepulse with the mask:a/ RECALL 8, (Ensure CH1 Impedance is reset to 1MΩ. SelectTRIGGER, SETUP and set softkey to ).b/ DEFINE MEASDIRECTORYCHANGE DIRECTORYTELECOM MASK/MASKLOAD SETUP 8 M1M2PATTERN TRIGGER Trig’d
