Snell & Wilcox IQBADX-2-D User manual

IQBADX SECTION 28c
IQBADXOPS 050804 www.snellwilcox.com Version 1 Issue 5 28c.1
IQBADX Four Channel Analog and D1
AES/EBU Audio Data Extractor
Module Description
The IQBADX extracts four audio pairs from SDI
video (D1 - 270MBit) to four analog and four
AES/EBU outputs. 20-bit digital to analogue
conversion ensures high audio signal quality.
A crystal locked PLL ensures low output jitter.
The analog audio output level is adjustable
between +12 and +24 dBu for 0 dB FS in via preset
trimpots. Extraction may be from any group and
pair independently for each channel-pair.
Extraction is fully compliant with SMPTE 291M and
SMPTE 272M-A for synchronous-to-video audio at
48 kHz.
When audio data is absent from a selected
channel-pair address, the output will be silence or
tone (selectable).
The SDI input is equalized to > 200 m of cable.
Full EDH monitoring is included. All analogue audio
connections are via a 25 way D connector. AES
connections are balanced via a 25 way D
connector (-D versions) or unbalanced BNC (-B
versions).
REAR PANEL VIEWS
IQBADX-2-D
SERIAL IN
SERIAL OUTPUTS
AUDIO OUTPUTS
123
GPI
AES REF
IQBADX-2-B-0
SERIAL IN
AES OUTPUTS
AUDIO OUTPUTS
123
AES REF
4
C

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Versions of the module cards available are:
IQBADX-2-D Balanced Analog + AES Outputs + GPI Input, 4 SDI Outputs Double width module
IQBADX-2A-D Balanced Analog + AES Outputs + GPI Input, 4 SDI Outputs Double width module
IQBADX-2-B 4 Balanced/Unbalanced AES Outputs and analog outputs Double width module
IQBADX-2A-B 4 Balanced/Unbalanced AES Outputs and analog outputs Double width module
Note that there are two styles of rear panels available. They are not interchangeable between the two
styles of enclosures. However, the cards may be fitted into any style of enclosure.
‘A’ Style Enclosure
Rear panels with the suffix A may only be fitted
into the ‘A’ style enclosure shown below.
IQ
(Enclosure order codes IQH3A-E-0, IQH3A-E-P,
IQH3A-0-0, IQH3A-0-P)
‘O’ Style Enclosures
Rear panels without the suffix A may only be fitted
into the ‘0’ style enclosures shown below.
setup
lock save
rec all
modules help
adjust
scro ll
power previous
return
home
contro l
information
display
sele ct
power
(Enclosure order codes IQH1S-RC-0, IQH1S-RC-
AP, IQH1U-RC-0, IQH1U-RC-AP, Kudos Plus
Products)
power
OPEN
(Enclosure order codes IQH3N-0, IQH3N-P)
(Enclosure order codes IQH3U-RC-0, IQH3U-RC-
P)

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BLOCK DIAGRAM
RollCall™
Processor
Deserialize Audio
Extract
Audio
Extract
Audio
Extract
Audio
Extract
7 x Tone
Silence
3xSDI
Outputs
(-D version only)
EDH
Check
LR Map Extract/Tone/Silence
SDI
Input
AES Reference
Input
Receiver
ANC
Status
AES OUTPUTS
1
2
3
4
GPI (-D version only)
Audio Clock
Clock/PLL
Analog Outputs
Left 1
Right 1
Left 2
Right 2
DAC
DAC
DACDAC
DAC
Features
Demultiplexes four audio pairs from serial 4:2:2 video
•Simultaneous Analog and AES/EBU digital outputs
•Audio extraction independently selectable by pair
•Channel 1/2 mapping (1/2,2/1,1/1,2/2)
•20-bit digital to analog conversion, -95 dB THD+N (FS)
•Analog output level manually adjustable +12 to +24 dBu for 0 dB FS in
•Crystal PLL for low jitter
•Automatic 525 and 625 line operation
•Embedded audio presence indication
•7 internal precision tones or silence selectable for output
•EDH monitoring
•RollCall control
•General Purpose control Input (GPI) (-D version only)
•Balanced (D-type) or Unbalanced (BNC) AES versions

IQBADX SECTION 28c
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TECHNICAL PROFILE
Features
Signal Inputs
Digital Video....................... 1 Serial (D1-270) via BNC
GPI .................................... 1 via BNC (-D only)
AES Audio ......................... 1 AES Reference (48 kHz,
synchronous to input SDI only)
Standards .......................... SMPTE 259M-C–1997, SMPTE
272M-A-1994
Signal Outputs
Analog Audio ..................... 4 Channels (2 Stereo Pairs)
Digital Video....................... 3 Reclocked SDI (-D only)
AES/EBU Audio ................. 4 Stereo pairs
(balanced/unbalanced)
Standards .......................... SMPTE 259M-C–1997, SMPTE
272M-A-1994, AES3-1992
Specifications
Serial Input Return Loss..... Better than 15 dB to 270 MHz
Serial Input Receive length >200 m
Analog Audio Outputs ........ Level Manually Adjustable +12 dBu
to +24 dBu
Output Impedance 45 to 55 ohms
AES Audio Outputs ............ Typically 3 V pk to pk into
110 ohms (Transformer Balanced)
via 25 way `D’ connector
AES Audio Outputs ........... (Unbalanced) Typically 1 V pk to pk
into 75 ohms via BNC
THD+N .............................. -95 dB typical at 1 kHz
Dynamic Range ................. 105 dB
Conversion ........................ 20-bit
Sampling............................ 48 kHz Synchronous to SDI video
stream
Power Consumption
Module Power Consumption
11 W max

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INPUTS
Serial Digital Video Input
The serial digital input to the unit is made via this
BNC connector which terminates in 75 Ohms.
AES Reference Input
The AES reference input connection is made via a
BNC connector.
If a suitable AES reference signal is present the
digital outputs will be frame-synchronised to this
signal. (48 kHz only).
SERIAL IN
IQBADX-2-B/-D
IQBADX-2A-B/-D
SERIAL INAES REF
IQBADX-2-D
AES REF
IQBADX-2-B-0
IQBADX-2A-D

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OUTPUTS
IQBADX-D/-2A-D
Analog and AES audio output connections are
made via the 25 way female D-type connector.
There are four balanced analog and four balanced
AES outputs available.
For connection data consult the tables on page 5.
If a suitable AES reference signal is present the
digital outputs will be frame-synchronised to this
signal. (48 kHz only).
IQBADX-B/-2A-B
Analog audio output connections are made via the
25 way female D-type connector. There are four
balanced analog outputs available.
For connection data consult the tables on page 5.
IQ
B
AUDIO OUTPUTS
IQBADX-2-D
IQBADX-2A-D
IQ
B
AUDIO OUTPUTS
IQBADX-2-B
IQBADX-2A-B

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AES audio output connections are made via these
four BNC connectors. There are four unbalanced
AES outputs available.
Serial Digital Video (IQBADX-2-D/-2A-D only)
These are the three isolated Serial Digital outputs
of the unit via BNC connectors for 75 Ohms.
AES OUTPUTS
1234
IQBADX-2-B-0
IQBADX-2A-B
SERIAL OUTPUTS
123
IQBADX-2-D
IQBADX-2A-D

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Connection Details IQBADX-D
25 Way D Connector
Pin Number Description
Ribbon Cable
Strand Number Standard Pin Assignment
1 Chassis 1 CHASSIS
14 ANALOG OUT 1 GND 2 GND1
2 ANALOG OUT 1 + (Left) 3 1+
15 ANALOG OUT 1 - ( Left) 4 1-
3 ANALOG OUT 1 + (Right) 5 2+
16 ANALOG OUT 1 - (Right) 6 2-
4 ANALOG OUT 1 GND 7 GND2
17 ANALOG OUT 2 GND 8 GND3
5 ANALOG OUT 2 + (Left) 9 3+
18 ANALOG OUT 2 - (Left) 10 3-
6 ANALOG OUT 2 + (Right) 11 4+
19 ANALOG OUT 2 - (Right) 12 4-
7 ANALOG OUT 2 GND 13 GND4 (CH)
20 GND 14 GND5
8 AES OUT 1 + 15 5+
21 AES OUT 1 - 16 5-
9 AES OUT 2 + 17 6+
22 AES OUT 2 - 18 6-
10 AES 2 GND 19 GND6
23 AES 3 GND 20 GND7
11 AES OUT 3 + 21 7+
24 AES OUT 3 - 22 7-
12 AES OUT 4 + 23 8+
25 AES OUT 4 - 24 8-
13 AES 4 GND 25 GND8
Connection Details IQBADX-B
1 Chassis 1 CHASSIS
14 ANALOG OUT 1 GND 2 GND1
2 ANALOG OUT 1 + (Left) 3 1+
15 ANALOG OUT 1 - ( Left) 4 1-
3 ANALOG OUT 1 + (Right) 5 2+
16 ANALOG OUT 1 - (Right) 6 2-
4 ANALOG OUT 1 GND 7 GND2
17 ANALOG OUT 2 GND 8 GND3
5 ANALOG OUT 2 + (Left) 9 3+
18 ANALOG OUT 2 - (Left) 10 3-
6 ANALOG OUT 2 + (Right) 11 4+
19 ANALOG OUT 2 - (Right) 12 4-
7 ANALOG OUT 2 GND 13 GND4 (CH)
20 GND 14 GND5
8 Not Used 15 5+
21 Not Used 16 5-
9 Not Used 17 6+
22 Not Used 18 6-
10 GND 19 GND6
23 GND 20 GND7
11 Not Used 21 7+
24 Not Used 22 7-
12 Not Used 23 8+
25 Not Used 24 8-
13 GND 25 GND8
Example of Connection Details to XLR Connectors

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Analog Output 1 Left
Analog Output 2 Left
AES Output 1
AES Output 3
Analog Output 1 Right
Analog Output 2 Right
AES Output 2
AES Output 4
Analog Output 1 Right
Analog Output 2 Right
Not Used
Not Used
Analog Output 1 Left
Analog Output 2 Left
Not Used
Not Used
IQBADX-B
IQBADX-D

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CARD EDGE CONTROLS
Note that the unit will respond to both local and remote control, one system overriding the settings of the other
For cards using the RollCall remote control system, activating these switches will override the remote control
settings. The RollCall control panel will then follow these settings.
Note that in Main-frames where RollCall™ is not
available the REMOTE link (see opposite) should
be set to the OPEN (OFF) position. This ensures
that when the unit is powered-up the factory default
settings of parameters not available as card edge
adjustments, are loaded. With the link in the
CLOSED (ON) position the card will power-up with
the last settings stored in the non-volatile memory.
LED INDICATORS
PWR (Power)
These two PWR indicators are illuminated when
the positive and negative supplies are present.
D1 Loss
This LED will become illuminated when there is no
D1 input.
ANC ERROR
This LED will become illuminated for a period of
time each time a checksum error is detected in the
embedded ancillary data packets.
NO LOCK
If the card is expecting to phase up the AES
outputs to a reference which is not present this
LED will illuminate.
If the applied AES reference is not synchronous to
the input SDI it will be rejected and this LED will
flash.

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STATUS LED’s
These LED’s will
1. Become illuminated when either Tone or
Silence is selected.
2. Flash if there is no AES at the selected
address.
3. Will not be illuminated if the extractor channel
is working.
EDH PRESENT / ERROR
This LED will become illuminated if the input D1
video has embedded EDH data.
This LED will also briefly blink off whenever the
EDH checksum errors are detected.
EDH MINUTE / HOUR
These LED’s provide the EDH error minute & hour
history indicating occurrence of errors within their
respective time periods.
These LED’s will remain OFF if no errors have
occurred within their time period, or it the incoming
D1 video does not contain EDH data.
BCD SELECT SWITCHES
These switches select which embedded channel or
tone/silence is to be output.
Settings are as follows:
1 to 8 select stereo pair for extraction
1 group 1, pair 1 (Pair 1)
2 group 1, pair 2 (Pair 2)
3 group 2, pair 1 (Pair 3)
4 group 2, pair 2 (Pair 4)
5 group 3, pair 1 (Pair 5)
6 group 3, pair 2 (Pair 6)
7 group 4, pair 1 (Pair 7)
8 group 4, pair 2 (Pair 8)
9 test-tone
0 silence

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4-WAY DIP SWITCH
Setting to the DOWN (ON) position enables the
function.
POSITION 1 TONE / SILENCE
Selects tone (down) or silence (up) for the output in
the event of an extraction failure.
POSITIONS 2 and 3
These positions are not used.
POSITION 4 EDH RESET
When enabled this will clear EDH error history.
SMPTE 272M SUPPORT
The cards conform to SMPTE 272M-A
A synchronous audio at 48 kHz;
20-bit audio data packets
The cards do not support
SMPTE 272M-B,C,D,E,F,G,H,I,J
B synchronous audio for composite video
C 48 kHz synchronous, with audio & extended
data packets
D asynchronous audio
E 44.1 kHz audio
F 32 kHz audio
G 32 kHz to 48 kHz continuous sampling rate
range
H audio frame sequence
I time delay tracking (monitor only)
J non-coincident ‘Z’ bits in a channel pair

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ALIGNMENT OF ANALOG OUTPUT LEVELS
The relationship between audio levels in the digital
and analog domains is set via four multi-turn
trimpots one per output channel.
The adjustment range is +12 dBu to +24 dBu
output for 0 dBFS digital audio level.
The generalised relationship is:
Analog (dBu) = Digital (dBFS) + Headroom (dB)
For Example:
Digital audio level = -20 dBFS
Required analog headroom = +18 dB
Analog level for -20 dBFS = -20 +18 = -2 dB
To re-align the analog outputs for different
headrooms a known digital audio level has to be
applied.
This can be done either by de-embedding an
embedded tone or the card's internal tone
generator may be used.
In all cases the card must be supplied with a valid
SDI digital video source.
Using the card's internal tone generator:
Connect the analog outputs to an audio level
meter.
Via RollCall, set outputs 'A' and 'B' to
'0dBFS_1kHz'.
Adjust the multi-turn trimpots for the required
analog headroom.
Using an SDI feed with embedded tone:
Connect the analog outputs to an audio level
meter.
Via RollCall or the card edge controls configure
de-embedders 'A' and 'B' to extract the test signal.
Adjust the multi-turn trimpots for the required
analog level.
Trimpot Functions
Output_A Left (Analog output 1, Left) ............... RV1
Output_A Right (Analog output 1, Right)........... RV2
Output_B Left (Analog output 2, Left) ............... RV3
Output_B Right (Analog output 2, Right)........... RV4

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OPERATION FROM AN ACTIVE CONTROL PANEL
The card may be operated with an active control panel via the RollCall™ network.
The menus available for this card are shown on page opposite and will appear in the Control display window.
Operational details for the remote control panel will be found in SECTION 1 of the Modular System Operator's
Manual.
MENU DETAILS
(see IQBADX Menu System Opposite)
MAIN MENU
The main, or top level menu allows various sub-
menus to be selected by pressing the button
adjacent to the required text line.
Note that where a menu item is followed by three
dots (...) this indicates that a further sub-menu may
be selected.
Whenever a menu item is selected the parameters
of that selection will be displayed in the Information
window of the front panel. Where the selection is
purely a mode selection and does not enable a
sub-menu, the text will become reversed (white-on-
black) indicating that the mode is active. If the
mode is not available for selection the text will
remain normal.
◀
◀◀
◀Outputs
The outputs can be set to any of the eight possible
embedded audio addresses, or can be fixed to an
internally generated test signal (tone or silence).
Display ▶
▶▶
▶
The status of the embedded data on the input D1
stream (select Embedded_D1), and the extractor
outputs (select Audio_Outputs) may be monitored
here.
The information to be displayed in the LCD
window.
◀
◀◀
◀Extract
An output may be selected and various processes
applied to that output.
This menu allows the left and right channels to be
inverted and, using the Extract function,
the output channels may be reformatted.

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EDH ▶
▶▶
▶
The input D1 stream is continuously monitored for
EDH errors. Basic information on this can be
monitored and/or reset here.
The following functions may be selected:
◀
◀◀
◀Show_Stats The information will be
displayed in the LCD
window
For example:
◀
◀◀
◀Reset_Stats Data will be reset
Factory preset is to Show_Stats.
◀Memory
This function reveals a sub-menu that allows
control of the user memories.
◀
◀◀
◀Read_Memory
This function reveals a sub-menu which allows 4
different settings of all items to be recalled from the
4 memory locations as saved in the Save_Memory
function.
◀
◀◀
◀Save_Memory
This function reveals a sub-menu which allows the
settings of all items to be saved. Up to 4 different
set-ups may be saved in the 8 memory locations.
They can all be renamed using the
Name_User_Memory menu item.
◀
◀◀
◀Name_User_Memory
This selection allows renaming of memory 1 to 4
locations.
To rename a memory location when operating in a
particular standard, select:
◀Name Memory to reveal the sub-menu.
Select the memory location to be renamed e.g.
◀Memory_1
To compile/edit the text the right ▶and left ◀
buttons adjacent to the upper text line in the menu
should be used to select the character position in
the text and the spinwheel used to select the
character.
The ◀Clear function blanks out the selected
character.
The ◀Preset function loads the default text.
O.K. ▶saves the caption text and returns to the
main menu.
◀
◀◀
◀Clear_User_Memory
This selection allows individual memory locations
to be cleared and returned to their default (factory)
settings.

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◀Setup
◀
◀◀
◀Lock_To_Ref
The AES outputs from the extractor are mutually
synchronised, in that their sample frames are co-
timed.
If a suitable AES reference signal is present the
digital outputs can be frame-synchronised to it by
activating this function.
Factory setting is enabled.
◀
◀◀
◀GPI
The GPI connector is used for accepting GPI
information (from mechanical switch contacts,
relay contacts etc.) The resulting action that the
unit takes may be selected from this menu.
◀
◀◀
◀GPI-Trigger_Setup
The trigger input has 3 user selectable modes of
operation:
◀
◀◀
◀Off
When selected the function is not active
◀
◀◀
◀Latch
When the contact is closed the function is
activated; when the contact is open, the function is
de-activated.
◀
◀◀
◀ Edge
(Edge-triggered) With each open-to-closed trigger
the GPI function is toggled between activated and
de-activated.
◀
◀◀
◀GPI_Function
The action resulting from the GPI input being
activated may be programmed from this list:
◀
◀◀
◀Output_A_Silence (output A will be silence)
◀
◀◀
◀Output_B_Silence (output B will be silence)
◀
◀◀
◀Output_C_Silence (output C will be silence)
◀
◀◀
◀Output_D_Silence (output D will be silence)
◀
◀◀
◀Output_A_Tone (output A/B/C/D will be a
◀
◀◀
◀Output_B_Tone tone as selected from the
◀
◀◀
◀Output_C_Tone Tone_Outputs menu)
◀
◀◀
◀Output_D_Tone
◀
◀◀
◀Trigger_Memory_1 (settings stored in
◀
◀◀
◀Trigger_Memory_2 the memory location
◀
◀◀
◀Trigger_Memory_3 will be activated)
◀
◀◀
◀Trigger_Memory_4

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◀
◀◀
◀Set_Default_Output
The outputs are always active. In the event of an
extraction failure (due to there being no data at the
targeted address) an internally generated signal
may be selected as the output for both Output A or
Output B.
Selections are as follows:
◀
◀◀
◀Silence
◀L/R_Tone (Left = -20 dBFS at 1 kHz
Right = -20 dBFS at 500 Hz+2 kHz
mixed)
◀-20dBFS_L/R_Tone
◀
◀◀
◀-20dBFS_1KHz
◀
◀◀
◀-20dBFS_500Hz
◀
◀◀
◀-20dBFS_250Hz
◀
◀◀
◀-60dBFS_1KHz
◀
◀◀
◀-1dBFS_1KHz
◀
◀◀
◀0dBFS_1KHz Preset setting is to silence.
◀
◀◀
◀Tone_Output
An internally generated tone signal may be
selected as the output for Output A, B, C or D.
◀L/R_Tone (Left = -20 dBFS at 1 kHz
Right = -20 dBFS at 500 Hz+2 kHz
mixed)
◀
◀◀
◀-20dBFS_1KHz
◀
◀◀
◀-20dBFS_500Hz
◀
◀◀
◀-20dBFS_250Hz
◀
◀◀
◀-60dBFS_1KHz
◀
◀◀
◀-1dBFS_1KHz
◀
◀◀
◀0dBFS_1KHz
Preset setting is L/R_Tone.
◀Names
Default names are given to the outputs and the
possible embedded inputs which are little more
than relative descriptions. These names may be
edited to provide more meaningful information
related to the equipment installation.
To edit a name select either
◀
◀◀
◀Output_Names
or
◀
◀◀
◀Input_Names
or
◀
◀◀
◀Preset_Names (returns to default names)
Selecting Input Names will reveal a menu that
allows an input location to be selected i.e.
Select the desired location (this will reveal an
editing window) and edit the name using the
spinwheel/push buttons. (Use same method as for
naming the memory names)
Selecting Output Names will reveal a menu that
allows an output location to be selected i.e.
Select the desired output (this will reveal an editing
window) and edit the name using the
spinwheel/push buttons. (Use same method as for
naming the memory names)

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◀
◀◀
◀Logging
If a logging device is attached to the RollCall™
network, information about various parameters will
be reported to the logging device assigned in the
Remote Control Interface system. (See Section 1,
The RCIF Menu System)
The logging sub-menu allows the following
information to be made available for logging:
Factory preset is nothing enabled.
◀
◀◀
◀Preset_Unit
Selecting this item sets all adjustment functions
that include a preset facility, to their preset values.
Note that this is a momentary action and the text
will not become reversed.
◀
◀◀
◀Software_Version
Selecting this item reveals a display showing the
version of the software fitted in the module.
Select OK to return to the System Menu.
◀
◀◀
◀Serial_Number
Selecting this item reveals a display showing the
serial number of the module.
Select OK to return to the System Menu.

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Extractor Operation
The SMPTE 272M standard specification allows for
up to four groups of digital audio to be embedded
in a component D1 digital video stream.
Each group consists of two stereo pairs (four
channels), giving a total of sixteen audio channels
for all four groups.
A single IQBADX module is capable of extracting
four stereo pairs, or eight channels, so two
IQBADX cards are required to extract all sixteen
possible channels.
The embedded AES audio data must be sampled
at 48 KHz, clock synchronous to the video stream.
Asynchronous operation is not supported.
The IQBADX module contains four independent
extractors, each one assignable to any of the
possible embedded audio pairs. If any of the
extractors are set to the same address they all will
output that extracted pair. Additionally, any output
can provide an AES test tone (1 KHz, -20 dB) or
‘digital silence’.
A total of exactly 1920 audio samples occur within
one frame of 625-line video. For 525-line video the
relationship is 8008 audio samples over five video
frames.
The audio data is usually distributed evenly
throughout each video frame, situated in the non-
active picture regions between the end of one line
and the start of the next. The majority of lines
contain three audio samples, some four, and
certain reserved lines may contain no samples.
Other sample counts are also possible.
These differences in sample count between lines
mean that some FIFO buffering is required to
supply output audio samples during lines
containing no samples, and to absorb the excess
from lines with several.
An audio extractor should be able to process
ancillary packets where ever and whenever they
appear. However, there are usually practical and
operational limitations such as the finite length of
the extractor FIFO buffer, and the length of the
audio delay introduced by the buffering process.
IQBADX FIFO Buffer Length :
A FIFO buffer requires that before any samples are read out a minimum number must be written in. This
number determines the latency (delay) and implies limitations on the embedded sample distribution. So-called
‘smart buffers’ make assumptions about the distribution of audio samples within the video frame and so can
utilise smaller FIFOs. The 24-bit sample distribution given in SMPTE-272M for example requires a ‘smart
buffer’ length of 57 samples with a read-write offset of 17 samples. A simple buffer however needs to be 80
samples long with 40 samples offset. In both cases the buffers can handle a maximum change in usage of 40
samples but the ‘smart’ buffer knows when this happens and so can use less memory and have a lower
latency.
For any known sample distribution the required buffer capacity can be calculated. The simple buffer needs to
be twice this in length
SMPTE-272M, 24-bit example 40 samples
Panasonic D5 VTR, 625 lines 6 samples
Sony Digital Betacam, DVW-500P 5 samples
S&W IQBAI / BAIR inserter modules 14 samples
Tektronix TSG-422 7 samples
S&W MDD-3000 digital decoder 7 samples