Newport 500B Series, User Manual, Page: 31 / 64

30 System Operation
4.1.8 Control Knob
Located on the right side of the front panel, this knob is used to set the
appropriate drive current when the display is in either SETPOINT or LIMIT
SET modes.
4.2 Rear Panel
The Model 500B Series rear panel shows the OUTPUT connectors, a
REMOTE/LOCAL switch, the photodiode reverse voltage BIAS ADJUST
screw, a photodiode BNC input, the BANDWIDTH selection switch, and the
AC power inlet.
Figure 13 Rear Panel
4.2.1 USB Interface
The instrument is designed to communicate with standard USB interfaces.
The cable required is a USB A/ B connection cable.
4.2.2 PD Bias Adjustment
A monitor photodiode may be reverse biased up to -5 volts using the
PD BIAS adjustment screw. In the farthest clockwise position the
photodiode is zero biased. Turning the screw counter-clockwise increases the
bias voltage.
Photodiode
BNC Connector
USB
Port
Voltage
Setting &
Fuse
Model
Number
Label
CE
Label
Photodiode
Bias Pot
Low/Hi
Bandwidth
Switch
Laser Diode
Driver Output
Power