PROCEDURES

PROFILE OPERATION MODE

 

cussed more fully in the Triggered Measurements section

 

below.

 

Range Hold may be selected (see page 4-6) to limit dy-

 

namic range and prevent small range change distur-

 

bances on very high speed signals. Use Range Hold 1 for

 

measurements down to –25 dBm, and Range Hold 2 up

 

to –25. If the display update is turned off via GPIB, only

 

the average is updated.

Triggered

Since non-triggered measurements are of limited use in the PROFILE mode,

Measurements

most applications require triggering. For example:

 

1. Provide a 1 kHz square wave modulated signal to sensor A, and set

 

TRIGGERSETUPMODE to Internal A (Int A). This causes the PROFILE sweep

 

to wait until a certain power level is present on the sensor before starting the

 

sweep.

 

2. The DELAY and WIDTH parameters, as discussed above, are the positions of

 

the two CURSORS. These can be set to specific locations; for example, if the sig-

 

nal is a 1 kHz square wave, setting the DELAY to 250 s places the cursor in the

 

first cycle at the midpoint of one of the phases. Setting the WIDTH to 500 s sets

 

the other CURSOR to exactly one half-cycle later, thus allowing display of the

 

power levels in the two phases of the signal.

 

NOTE

 

If the modulation is turned off, then the trigger conditions

 

will not be met and the sweep will not continue to be up-

 

dated. This is useful to ‘freeze’ a display. To display a CW

 

signal again, re-select CONTINUOUS trigger in TRIG-

 

GERSETUPMODE.

 

In some conditions, it is useful to view triggered signals

 

independent of signal levels. In these cases, provide an

 

external trigger source into the rear panel TRIGGER input

 

to trigger such a measurement.

 

3. The dynamic range in PROFILE mode should extend to the maximum specifi-

 

cation of the meter, to approximately –40 dBm (diode sensors only). If the dis-

 

played range is restricted, check that RANGE HOLD is not applied.

NOTE

If RANGE HOLD 1 is applied, the lower limit will be ap- proximately –30 dBm. If RANGE HOLD 2 is applied, the maximum level will be limited to approximately –10 dBm. In most triggered situations, range hold should be set to AUTO.

ML2430A OM

5-13

 

 

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Image 76
Anritsu ML2430A operation manual Triggered, Measurements, Gersetupmode