Language Reference

MEASU

Example Use the MEASU and POSU commands to position graphics on the analyzer display in measurement units and in position units.

10

CLEAR 723

Initialize analyzer .

 

20

OUTPUT 723;"IP;"

 

 

30

OUTPUT 723;"CLRDSP;"

Clear graphics from memory .

 

40

OUTPUT 723;"SP 10NM;CENTERWL 1300NM;TS;"

Set measurement range .

 

50

OUTPUT 723;"SCALE 0,800, 011003,502;"

Set graphics scale for the display of traces .

60

OUTPUT 723;"PU;PA 0,MEASU 037DBM,TRA;"

Place the pen on the left edge of the graticule

 

 

at 037 dBm.

 

70

OUTPUT 723;"PD;PA POSU 1300NM,TRA,MEASU -22DBM,TRA;"

Draw line to the point at 1300 nm and

022

 

 

dBm.

 

80

OUTPUT 723;"PU;PA 0,MEASU -25DBM,TRA;"

Move pen to the left edge of the graticule

, at

 

 

025 dBm.

 

90

OUTPUT 723;"PD;PA 800,MEASU -30DBM,TRA;"

Draw a line to the right edge of the graticule ,

 

 

ending at 030 dBm.

 

Description The MEASU command converts parameter-unit values to measurement-unit values. Measurement units describe trace amplitude information.

￿For linear trace information, measurement units are de￿ned as 0 (zero) for the bottom of the display, and 10,000 for the top of the display. A measurement unit equals the reference level/10,000:

measurement units = (value in reference level values) ((reference level)(10; 000))

￿For logarithmic trace information, the range of trace data is 032,768 measurement units to +32,767 measurement units. A measurement unit is one hundredth of a dBm:

measurement units = (value in dBm) (100)

Parameter units are standard scienti￿c units:

Parameter Units for Amplitude

Decibels Watts

W

dBm mW nW pW

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