Setup panel selections

Using the Optical Spectrum Analyzer

The Amplitude Menus

Reference Level Position

The value selected for the Reference Level Position determines the position of the reference level on the graticule. Setting this value to zero divisions places the reference level on the very bottom of the grid. Setting the reference level to 10 divisions places the reference level at the top of the grid. Pressing the front-panel Preset key resets the reference level to 9.0 divisions.

Note

When using the knob or step keys, the value will automatically change. When using the numeric entry pad, a terminator must be selected from the softkey panel.

Amplitude Units

Selecting Auto for amplitude units allows power to be shown in dBm when using the logarithmic scale and in watts when using the linear scale. Selecting W forces the readout to be in watts, regardless of the amplitude scaling.

Auto Ranging

The Auto Range function allows the OSA to change the gain of the transim- pedance amplifier during a sweep. This provides measurements to be made at the widest dynamic range and at the fastest sweep speed.

Pressing the front-panel Preset key turns Auto Ranging ON.

Note

It is recommended that Auto Ranging always be turned ON.

Auto Zero

Turns Auto Zero ON and OFF. Auto Zero ON enables the internal amplifiers to be zeroed between sweeps. Selecting OFF disables this feature. Pressing the front-panel Preset key resets this function to ON.

Note

Turning Auto Zero OFF allows the instrument to sweep faster, but results in less accuracy on low level signals.

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