P6701B and P6703B PerformanceVerification
10 P6701B, P6703B, and P6723 Service Manual
1. Connect 1310 nm laserto attenuator.
NOTE. The longer wavelengths of 1310 nm and especially 1550 nm are more
sensitive to loss in fiberdue to bending of the fiber than the short wavelength.
The fiber bend radius of the P670XB fiberinput should lay with >1-inch bend
radius along the fiber’sentire length. Although this precaution must be
maintained throughoutthe entire PV procedure, it is especially important for this
step in orderto accurately adjust and measure DC-conversion gain of the
P670XB.
2. Connect FC connector of the opt ical attenuator to the FC receptacle of the
optical powermeter using optical cable; use the appropriate optical power
meter sensing head with calibrated measurement for a wavel ength span
including 1310 nm and 1550 nm. Be sure theoptical power meter wave-
length setting is at 1310 nm.
3. Adjust the attenuator or opticalsource so that the power meter reads 100 W.
4. Move the FC fiber end(the one now adjusted to 100 W average power)
from the opticalpower meter and connect to the P670XB input under test by
using the FC-FC inline female-femaleoptical adapter.
5. Attach voltmeterwith 50 ohm termination to 1103 powered P670XB output.
6. Check for 100 mV readingon voltmeter, ±8%. (The 1310 nm Conversion
Gain is 1.00 V/mW.)
AC Conversion Gain
1. Connect the probe under test to the 11Kseries oscilloscope and to the cal
source.
HIf the unit undertest is a P6701B, connect the 850 nm modulated laser
source to the optical attenuatorinput. C onnectthe output of the optical
attenuatorto the P6701B input via an inline adapter.
HIf the unit undertest is a P6703B, connect the 1310 nm modulated laser
source to the optical attenuatorinput. C onnectthe output of the optical
attenuatorto the P6703B input via an inline adapter.
2. Adjust the laser cal sourceto provide a 10KHz to 20KHz optical square
wave on the scope.Adjust the optical attenuator so that the total peak-to-
peak signal fromthe P670XB is about 200 mV (or 200 W if the vertical
units displayed are “W”).

P6703B