Si Switchable Gain Detector, OEM
Chapter 3: Setup
Page 6
TTN235959-D02
4. The side adjusted potentiomete
r is used to adjust the voltage output’s
offset at high gain settings (e.g. 70 dB). This part is factory pre-adjusted
so normally the user does not need to adjust it. However, if the output
offset value has fallen out of spec, for example drift over time or
temperature, then it is possible to adjust it back by turning this
potentiometer. Turning the screw head clockwise decreases the offset
voltage and adjusting the screw head conterclockwise increases it.
Figure 4 Side adjusted potentiometer
5. Attach a 50
Ω coax cable to the output of the PDAPC1 detector. Thorlabs
offers two suitable cable options, the CA3339 MMCX to BNC cable or the
CA3439 MMCX to SMA cable.
When running cable lengths longer than 12", Thorlabs recommends
terminating the opposite end of the coax with a 50
Ω resistor for optimal
performance. Thorlabs Item # T4119 is suitable for this purpose.
Potentiometer
Adjustment
Screw Head
MMCX
Connector