New Focus 1580-A, Руководство пользователя

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12-GHz Photoreceivers Operation • 7
2.
Connect the power cable to the power supply. Two
power cables were included with the receiver; use
the appropriate cable for your power supply.
Connecting to a New Focus power supply:
Use
the cable with the two round microconnectors.
Connect one end of the cable to one of the power
supply’s 300-mA outputs.
Connecting to another power supply:
Use the
cable with the round microconnector on one end
and three banana plugs on the other end. Be
careful to connect the banana plugs to the power
supply as follows; connect the red plug to a well-
regulated, +15-V, 200-mA source; connect the
black plug to a -15-V, 200-mA source; connect the
green plug to the common ground of the two
sources.
3.
Connect the bias-monitor port to a voltmeter and
observe the voltage level on the voltmeter. This
voltage is the DC offset plus dark current. This
dark voltage should be less than 5 mV.
If you are coupling light into a fiber, use the voltmeter to
monitor the photocurrent to help optimize the coupling.
Microwave Connection and Set-up
1.
Connect the photoreceiver module’s microwave
connector to a test instrument that has a 50-
Ω
input, such as an oscilloscope or spectrum ana-
lyzer, or to another 50-
Ω
load. If necessary, use a
high-frequency cable (best performance is
achieved without a cable).
2.
To avoid connector damage and signal distortion,
be sure that the cable and the instrument you
intend to connect to the module have compatible
connectors. See “Appendix I: Microwave
Connectors” on page 15 for a list of compatible
connectors.
Note:
Note:
1580-A Rcvr revA.fm Page 7 Friday, May 10, 2002 3:07 PM