Si Switchable Gain Detector
Chapter 3: Setup
Rev D, April 21, 2020
Page 3
Chapter 3 Setup
The detector can be set up in many different ways using our extensive line of
adapters. However, the detector should always be mounted and secured for best
operation.
1. Unpack the optical head, install either an imperial or metric optical post
into one of the mounting holes located on the bottom and side of the
sensor, and mount using a post holder. Note that these detectors
feature tapped holes that accept both 8-32 and M4 threads, so using
either imperial or metric TR posts is possible.
2. Connect the power supply 3-pin plug into the power receptacle on the
PDA100A2.
3. Plug the power supply into a 50 to 60Hz, 100 V / 120 V / 230 V power
outlet.
4.
Attach a 50 Ω coax cable (i.e. RG-58U) to the output of the PDA. When
running cable lengths longer than 12" we recommend terminating the
opposite end of the coax with a 50
Ω resistor (Thorlabs p/n T4119) for
maximum performance. Connect the remaining end to a measurement
device such as an oscilloscope or high speed DAQ card.
Caution:
Many high speed oscilloscopes have input impedances of 50 Ω. In this
case, do not install a 50 Ω terminator. The combined loads will equal
25 Ω which could allow ~135 mA of output current. This will damage the
output driver of the PDA100A2.
5. Power the PDA100A2 on using power switch located on top side of unit.
Caution!
The active detector area in the PDA100A2 is offset from the front of the housing.
When using fiber adapters, make sure that the fiber ferrule does not crash into
the detector. Failure to do so may cause damage to the diode and/or the fiber.
6. Install any desired filters, optics, adapters, or fiber adapters to the input
aperture.
7. During alignment, take appropriate precautions, such as using reduced
radiation power, or other precautions, and use proper eye and/or skin
protection as recommended by the radiation source manufacturer.
8. Apply a light source to the detector. Adjust the gain to the desired
setting.
