H Heuer Instruments UMDT51A, Руководство пользователя

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LT51 User Manual x
4. Testing PLC Systems ........................................................................ 19
Measuring the Return Loss of Line Matching Units (LMU) .................. 23
Measuring the Blocking Impedance of Line Traps ............................... 24
5. Configuring the Tester ...................................................................... 25
LT51 Transmitter ................................................................................. 26
Output impedance ....................................................................... 26
Transmit source........................................................................... 26
Transmit level .............................................................................. 26
Transmit frequency ...................................................................... 27
Sweeping .................................................................................... 27
Sweep Step ................................................................................. 28
LT51 Receiver ..................................................................................... 29
Input Terminals............................................................................ 29
Input Impedance.......................................................................... 29
Input bridging .............................................................................. 29
Input level range .......................................................................... 29
AutoRange .................................................................................. 30
Interface ...................................................................................... 30
LT51 Frequency Bandwidth ................................................................. 31
Frequency span........................................................................... 31
Centre Frequency / Selective Level Meter .................................. 31
Bandwidth / Selective Level Meter .............................................. 32
AFC
– Automatic Frequency Control ........................................... 32
Averaging / Peak Hold ................................................................. 32
POTS Connection................................................................................ 33
Going “Off-Hook” ......................................................................... 33
Auto-Answer* .............................................................................. 33
Dialling ........................................................................................ 34
Redial .......................................................................................... 34
Speaker-Phone ........................................................................... 34
Marker functions .................................................................................. 35
Marker to peak ............................................................................ 35
Peak tracking............................................................................... 35
Next peak .................................................................................... 35
Zero offset ................................................................................... 35
Vertical offset............................................................................... 35
Volume control..................................................................................... 36
Adjusting the contrast of the LCD ........................................................ 36
Turning the backlight on and off .......................................................... 36
Switch-Off timeout ............................................................................... 36
Setting the date and time ..................................................................... 37
6. Making measurements ...................................................................... 39
Level (Spectrum measurements)......................................................... 40
Level (Numerical measurements) ........................................................ 42
Selective Level Meter .................................................................. 43