2 March, 2005
V1634OM.DOC
Page 12 of 12
4.
DAC OUTPUT MODULE
4.1 DESCRIPTION
The 130-2192 dual DAC output module features 24-bit DACs to accomodate future upgrade to 24
bit embedding in the SDI. Each channel pair - consisting of L and R channels - has digitally
controlled MOL which may be adjusted from +12dBu to +24dBu by the on-board hex switches SW1
band SW2. Each of the four analog outputs is quasi balanced 50
Ω
differential.
4.2 MAX
OUTPUT
LEVEL
SETTING
The MOL 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 V1634 is operated in local mode. Hex switch SW1 and
SW2 control MOL of channel pair A and B respectively and Table 4.2.1 below shows the MOL
settings for each hex switch position. The factory supplied shipping setting is +18dBu.
If the V1634 is connected to a DART compatible remote host and operated in remote mode, the
MOL 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
24dBu
4.3 CALIBRATION
The 130-2192 DAC output module has four trimming potentiometers R1, R2, R3 and R4, which
respectively trim the gain of the module’s digitally controlled gain block for analogue outputs AL, AR,
BL and BR. These potentiometers should not require adjustment by the user as they are accurately
set at the factory.
5.
AES OUTPUT MODULE
5.1 DESCRIPTION
The 130-2202 AES output module has dual AES outputs which, depending on the reference mode
selected, are either asynchronous or locked to SDI, external Black and Burst video or AES
reference source.
If the external Black and Burst video reference is selected, the unit will automatically synchronise to
525 /60 or 625/50 Black and Burst video input to the VID REF connector on the rear panel.
If the external 48kHz AES reference is selected, the unit will frequency lock both AES output
streams to the external AES applied to the AES REF connector on the rear panel, and will time-align
AES output frames and channel status blocks to those of the external AES reference.
If the selected reference source is disconnected or fails, the unit will automatically default to the
internal SDI reference.
