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VISTEK V1633/A & V1633/D
sdi audio multiplexer
HU-V1633/A&D
11
4.
ADC INPUT MODULE
4.1
Description
The 130-2172 dual ADC input module features 24-bit ADCs to accommodate future upgrade to 24 bit
embedding in the SDI. Each channel pair - consisting of L and R channels - has digitally controlled MIL
which may be adjusted from +12dBu to +24dBu by the on-board hex switches SW1 band SW2.
4.2
Max Input Level Setting
The MIL of each of the two channel pairs A and B may be set from +12dBu to +24dBu in 1dB steps by
means of the on-board hex switches if the V1633 is operated in local mode. Hex switch SW1 and SW2
control MIL of channel pair A and B respectively and Table 4.2.1 below shows the MIL settings for each hex
switch position. The factory supplied shipping setting is +18dBu.
If the V1633 is connected to a DART compatible remote host and operated in remote mode, the MIL may be
set remotely and the on-board hex switches are disabled.
Table 4.2.1
Switch Setting
MOL
0
+12dBu
1
+13dBu
2
+14dBu
3
+15dBu
4
+16dBu
5
+17dBu
6
+18dBu
7
+19dBu
8
+20dBu
9
+21dBu
A
+22dBu
B
+23dBu
C
+24dBu
others
+24dBu
4.3
Calibration
The 130-2172 ADC output module has four trimming potentiometers RV1, RV2, RV3 and RV4, which
respectively trim the gain of the module’s digitally controlled gain block for analogue inputs AL, AR, BL and
BR. These potentiometers should not require adjustment by the user, as they are accurately set at the
factory.