220 8163A/B, 8164A/B, 8166A/B User’s Guide
8 Setting Attenuation and/or Power Levels
How to Set Attenuation
Before applying an attenuation factor, set the Attenuator module to the
appropriate wavelength.
8157xA modules
The instrument utilizes a filter technology with a very low wavelength
dependence. Nevertheless, for the best possible accuracy:
• If the source is of a particular wavelength, set the Attenuator module to
that wavelength.
• If the source is a multi-wavelength DWDM signal, set the Attenuator
module to the weighted wavelength of the spectrum.
Figure 135 on page -220 shows an attenuation factor
α of 4.000 dB
applied to a 1550nm source.
Figure 135 Attenuation factor set to 4.000 dB