EXFO Photonic Solutions Div. FVA-600: 4 Operating the FVA-600 Variable Attenuator

Operating the FVA-600 Variable Attenuator 10

Using the Absolute Mode

The absolute mode displays the current wavelength and attenuation settings.

Note: The attenuation value is the actual insertion loss between the input and

output ports, including connectors.

Using the Relative Mode

The relative mode displays the current wavelength, the total attenuation, and the

relative attenuation. You need to set a reference before using the relative mode.

Note: The reference used is the one that was stored for the current

wavelength.

Current

Attenuation

wavelength

Relative

attenuation

loss/gain

If you vary the attenuation, the total attenuation introduced by the FVA-600 is

displayed in the top right corner, while the relative loss (or gain) with respect to the

selected reference is displayed in dB.

To take a reference:

Press and hold .

Select

While taking and storing the reference, the unit will

display REF for a short time. The unit returns to relative

mode using the new reference taken.

Using the Power Mode (Output

Power)

The power mode allows you to use the FVA-600 as if it was a power meter. This

operation mode uses the power value for the wavelength in use. It is a good practice

to edit this power.

To modify the power value:

1. Using the proper adapter, connect a power meter at the output of the FVA-600

and match the power meter value and the FVA-600 power value.

2. Press and hold to enter the power edition mode.

Select

3. Press the arrow buttons to go to the previous or

next power value. Hold them down to go to the

previous or next power value faster. You can also

change the power step size. See Setting Power

Step Size on page 12.

4. Press to confirm your selection.

Select

You can also exit the power edition mode by

pressing . However, the new power value will not be stored and the previous

power value will be used.

FVA-600 11

Operating the FVA-600 Variable Attenuator 12

Setting Attenuation Step Size

The unit has six preselected attenuation step sizes that allows you to vary the

attenuation more or less rapidly. The attenuation step size in use is stored when the

unit is turn off.

To select a step size:

Step

Press to switch between the available values.

Size

Setting Power Step Size

The unit has three preselected power step sizes that

allows you to vary the power in edition more or less

rapidly. The power step size in use is stored when the

unit is turn off.

To select a step size:

Step

Press to switch between the available values.

Size

Editing Wavelength

Six wavelengths are already preprogrammed in your unit. You can edit them to

better suit your needs.

To edit the wavelength value:

1. Press and hold to enter the wavelength

λ

edition mode.

2. Use the arrow buttons to go to the previous or next

wavelength value. Hold them down to change the

wavelength faster.

Note: An asterisk appears in the top right corner

of the unit when a manually selected value matches a calibrated

wavelength.

3. Press or to confirm your selection.

λ

Select

You can also exit the wavelength edition mode by pressing without selecting a

new wavelength.

Zeroing the unit

The Variable Attenuator contains mechanical elements used to change attenuation.

It is a good practice to have the instrument mechanism return to the zero (home)

position to reestablish its relative position on the range of attenuation.

To perform a zeroing:

Step

Press and hold .

Size

The screen displays ZERO while the zeroing is

performed. After the search is complete, the unit

returns to the attenuation that was previously in use.

Using the USB Port

The FVA-600 Variable Attenuator includes a USB port located on the side of the unit.

USB port

EXFO provides two installation kits to control the FVA-600 via the USB port.

³ One installation kit is for a computer using Microsoft Windows XP or

Vista (32/64 bits). This kit gives you the source code so you can set up a program

that better suits your needs. The source code is in C# and the project was

developed with Microsoft Visual Studio 2005.

³ The other installation kit is designed for the FTB-500. You can access the

application through the Tools (IPM) tab in ToolBox.

When you use either of the installation kits, the

remote-controlled unit displays REM. on its screen.

The unit returns to local mode when you exit the

software or if you disconnect from the USB port. The

screen displays RTL until you press a key, then the unit

can be controlled by the keypad.

FVA-600 13