EXFO FTB-7000 OTDR Series for FTB-500 - Manual (Page 239)

Using the OTDR as a Light Source or VFL
OTDR 225
5. Select the desired modulation.
With the Modulation dial,
³
For loss measurement, with a power meter at the other end, select
CW (to set the source to continuous output).
³
For fiber identification, select 1 kHz or 2 kHz. This will allow the
person at the other end of the link to identify the fiber under test,
which could be particularly useful when working with cables
containing many fibers.
For easier fiber identification, the application also offers a flashing
pattern. If you select this pattern, the modulated signal (1 KHz or
2 KHz) will be sent for 1 second, then will be off for the next
second, then be sent again for 1 second, and so on. If you want the
OTDR to emit light in a flashing pattern, select the Blink
Modulation at 1 Hz box.
6. From the Auto-Off box, select the duration after which you want the
laser to shut off. If you want to deactivate the automatic shut-off, simply
select Disabled.
7. Press Start. You can stop light emission at any time by pressing Stop.
Using an EXFO power meter with tone-detection features, such as the
FOT-930 or FPM-300, an operator at the other end will be able to quickly
locate the correct fiber or perform loss measurements. Refer to the power
meter user guide for details.
I
MPORTANT
Measurements using the CWsetting must always be taken using a
GeX detector.
An OTDR source is very powerful and it will certainly saturate Ge
and InGaAs detectors, which usually saturate at 6 dBm, while GeX
detectors saturates at 26 dBm.