Tektronix OI1125, Instruction Manual

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Operating Basics
16
OI1125 E/O Transmitter Instruction Manual
When the REMOTE pushbutton switch on the front panel is in the enabled
mode, the Enable LED is illuminated, and you control the transmitter operation
through the rear-panel remote interface. Refer to Figure 9 and Table 5 for the
connector pinout and signal descriptions.
In remote mode when no TTL signal is applied at the rear-panel connector, the
default state of all remote control inputs is high due to internal pull-up resistors.
The Remote Interface is implemented with a 25-pin, male D connector on the
rear panel. Figure 9 illustrates the pinout. The interface uses +5 volt logic levels,
and
±
2.5 volt analog control levels. It allows the remote control and monitoring
of the following parameters:
H
Laser lockout, laser power, and temperature monitoring
H
Variable extinction ratio enable, disable, and adjust
H
Modulator input detect and bias stability monitoring
H
Variable wavelength enable, disable, and adjust
H
Variable % Crossing enable, disable, and adjust
H
Front-panel control lockout
H
Front-panel laser keyswitch status
GND
GND
Laser Disable
ER Adjust Disable
Laser Power Unstable
GND Laser Temp Unstable
GND
GND
Wavelength Adjust
GND
ER Adjust
GND
Modulator Bias Unstable
Modulator Input Not Detected
Front Panel Unlock
1
14
Wavelength Adjust Disable
% Crossing Adjust
Not used
Laser Enable Keyswitch On
Not used
Not used
Not used
% Crossing Adjust Disable
GND
13
25
Figure 9: Remote Interface connector pinout
Table 5 lists the signal descriptions for the Remote Interface connector. Unless
otherwise noted, the signals are active in both local and remote operating modes.
Controlling Operation
Remotely
Remote Interface