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APPENDIX B
69
The communication, and signal output connectors for connecting to EMX-4250/51 card, are dual
25pin Micro D-Sub connectors, which are located at the rear side of BoB. The buffered output BNC
connectors are also located on the rear panel.
B
RIDGE
T
RANSDUCER
Voltage Excitation (EMX-4016M)
Two voltage excitation levels can be selected by two (2) front panel switches. One switch sets the
voltage for channels 1 to 8, and the other switch for channels 9 to 16. EMX-4016-001 can set the
excitation level remotely by the EMX-4250. The front panel switch needs to be in the “OFF”
position for the EMX-4250 to be able to remotely set the excitation level. Setting the front panel
switch to select one of the voltage excitation levels overrides remote control. Each channel has 2
LED indicators to show which excitation level has been selected. The left or right LED will turn
ON corresponding to the switch position.
AC
I
NPUT
C
OUPLING
The charts below shows the amplitude and group delay frequency response when coupling is set to
AC for the EMX-4250/4251, EMX-4350, and EMX-4380. This responses need to be combined with
the corresponding charts shown in the Anti-Alias Filter section to get the overall response of the
digitizer when they are set to IEPE or Voltage with AC coupling.
Figure 4-22: AC Coupling Voltage Magnitude Frequency Response
-12
-11
-10
-9
-8
-7
-6
-5
-4
-3
-2
-1
0
1
1.0E-1
1.0E+0
1.0E+1
1.0E+2
1.0E+3
N
or
maliz
ed
Amp
lit
u
d
e
(dB)
Frequency (Hz)
EMX-4350
EMX-4380
EMX-4250, 1kpC-10kpC
EMX-4250,100pC-500pC
NOTE: Buffer output in the 4016M will not work if the EMX-4250 is set to IEPE mode.
