B) Relative Power Measurement - VOLTCRAFT PM-22 Bedienungsanleitung

b) Relative power measurement

Perform a measurement at relative line measurement that serves as a reference. All further
measurements are compared to the first reference measurement and the difference is
displayed.
• Switch on the PM-22 (A4).
• Select the correct wavelength (A10).
• Remove the protective cap of the measuring input (A7).
• Connect the optical fibre cable that you want to use for reference measurement to the
measuring input (A7).
You may need to switch the adapter first. Observe chapter 8 b).
• After a brief wait, the measured result should be displayed. If required, wait until the display
has stabilised and a clear value is displayed.
• Now push the button "dB" to save the measured value as a reference.
The measured value previously shown in the main display (B3) is now displayed in the
secondary display (B6), also in the unit "dBm".
The unit of the main display (B3) switches to "dB" and should display "00.00".
The symbol B5 appears in the display.
• Now remove the connected optical fibre cable from the measuring input (A7) and connect
the second cable that you want to compare to the first one.
The secondary display (B6) still shows the value of the reference cable.
The main display (B3) shows the difference between the second measurement and the
reference measurement, in the unit "dB".
• To return to normal mode, push the button "dBm" (A6).
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