Wohler | ATSC/DVB-3/SDI | User manual | Wohler ATSC/DVB-3/SDI User manual

ATSC/DVB-3/M
2U Digital Audio Speaker Monitor
with HD/SD-SDI, AC-3, and AES Inputs/Outputs
on XLR/BNC, Analog Output of Selected on XLR,
Six 53-Segment Level Meters, Left/Right Source
Selection or Six Channel Mix, Status LEDs,
Headphone Output, and Phase Indication
(Document P/N 821650,Rev-B)
User Manual
CONTENTS
Title and Contents ............................................................. 1
Important Safety Instructions and Introduction ................................... 2
Section 1: General Features and Specs .................. 3
Description and Features .................................................................. 4
Applications and Specifications............................................................ 5
Installation .......................................................................................... 6
Section 2: Operation ............................................................ 7
Front Panel Features ........................................................................ 8
Rear Panel Features .......................................................................... 12
Section 3: Technical Information ................................ 15
General Technical Observations .......................................................... 16
Level Meter Settings and Specifications .............................................. 17
ATSC/DVB-3/M Interconnect Block Diagram .................................. 18
© 2007 Wohler Technologies Inc. ALL rights reserved
1
Important Safety Instructions
1)
Read these instructions.
2)
Keep these instructions.
3)
Heed all warnings.
4)
Follow all instructions.
5)
Do not use this apparatus near water.
6)
Clean only with dry cloth.
7)
Do not block any ventilation openings. Install in accordance with the manufacturer's instructions.
8)
Do not install near any heat source such as radiators, heat registers, stoves, or other apparatus (including
amplifiers) that produce heat.
9)
Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has two blades
with one wider than the other. A grounding type plug has two blades and a third grounding prong. The
wide blade or the third prong are provided for your safety. If the provided plug does not fit into your outlet,
consult an electrician for replacement of the obsolete outlet.
10) Protect the power cord from being walked on or pinched, particularly at plugs convenience receptacles
and the point where they exit from the apparatus.
11) Only use attachments/accessories specified by the manufacturer.
12) Use only with the cart stand, tripod, bracket, or table specified by the manufacturer, or sold with the
apparatus. When a cart is used, use caution when moving the cart/apparatus combination to avoid injury
from tip-over.
13) Unplug this apparatus during lightning storms or when unused for long periods of time.
14) Refer all servicing to qualified service personnel. Servicing is required when the apparatus has been
damaged in any way, such as when power-supply cord or plug is damaged, liquid has been spilled or
objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does not
operate normally, or has been dropped.
15) Do not expose this apparatus to rain or moisture.
16) The apparatus shall be connected to a mains socket outlet with a protective earthing connection.
CAUTION!
In products featuring an audio amplifier and speakers, the surface at the side of the
unit, where the audio amplifier heat sink is internally attached, may get very hot after
extended operation. When operating the unit excercise caution when touching this
surface and ensure that external materials which may be adversely affected by heat
are not in contact with it. There is a Hot Surface label (see diagram) attached to the
aforementioned surface of the product.
Introduction
Congratulations on your selection of a Wohler Technologies product. We are confident it represents the best performance and value
available, and we guarantee your satisfaction with it.
If you have questions or comments you may contact us at:
Wohler Technologies, Inc.
31055 Huntwood Avenue
Hayward, CA 94544
Phone: (510) 870-0810
Fax: (510) 870-0811
US Toll-Free: 1-888-596-4537
www.wohler.com
2
support@wohler.com
© 2007 Wohler Technologies, Inc. ALL rights reserved
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Sect. 1: General Features and Specifications
Section 1
General Features
and Specifications
Description
Features
Applications
Specifications
Installation
NOTE: Throughout this manual, the following terms are used to refer to Serial Digital (SDI) signals:
• SD-SDI = refers only to standard SDI (270 MB/s).
• HD-SDI = refers only to high-definition SDI (1.5 GB/s).
• HD/SD-SDI or SDI = refers to either standard SDI (SD-SDI, 270 MB/s) or high defintion SDI (HD-SDI, 1.5 GB/s)
© 2007 Wohler Technologies Inc. ALL rights reserved
3
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 1: General Features and Specifications
ATSC/DVB-3/M
2U Stereo Digital Audio Speaker Monitor
ATSC/DVB-3/M Front Panel
Description
The ATSC/DVB-3/SDI is a powered stereo monitor designed specifically for flexible, comprehensive monitoring of the six audio
channels associated with ATSC/DVB programming. The unit is 2RU in size, for excellent fidelity without using excessive rackspace
in the critical "operating zone" of rack bays and consoles. The ATSC/DVB-3/M model features an HD/SD-SDI input and reclocked
output on BNC connectors capable of accepting either standard SD-SDI or high definition HD-SDI audio signals, as well as
balanced XLR and unbalanced BNC inputs and loop-through outputs for monitoring PCM (Pulse Code Modulation), AES/EBU, and
AC-3 (Dolby Digital®) audio signals. HD/SD-SDI group and subgroup selection is set via front panel switches. Two XLR connectors
output analog audio of the sources selected for the left and right speaker channels.
The internal speakers and amplifiers are arranged in the popular Wohler “biamp summed bass stereo” configuration: bass
frequencies from ALL selected channels are summed into a 20 watt amplifier, which drives the woofer. The two side channel
amplifiers and speakers reproduce, in stereo, only the mid- and high-frequencies. Note that the center speaker (the woofer) is
NOT a dedicated Center nor LFE speaker. There is also a stereo headphone output, which mutes the speakers while in use.
Six high-resolution wide-range LED bargraph level meters are provided for all six channels for very accurate metering. Fifty-three
bi-color segments spanning a range of 65 dB simultaneously display signal levels according to both the PPM and VU standards.
Bargraph brightness is adjustable using two recessed trim pots on the front panel.
To isolate possible faults, two rotary switches on the front panel let the operator route any one or pair of inputs independantly
to left and right speaker channels for acoustic monitoring. A toggle switch is provided for mixing all six channels down to two for
listening to all channels at once.
Both Left/Right and Front/Surround "Phase"/Polarity LED indications are provided to alert of possible cancellation from mixdown
in any likely playback situation. The unit also features SDI, AC-3, and PCM status indication LEDs, Pro-16 select switch, and
power indication LED.
Features
• 2U high: highest fidelity in minimum rackspace
• Pro-16 signal select switch and indication LED
• Monitors HD-SDI or SD-SDI, AC-3 (Dolby
Digital), and PCM or AES audio signals
• Left/Right Front phase indication LEDs
• Simultaneous visual monitoring of all 6 channels
• Select any channel or pair of channels for isolated listening, or
a stereo mixdown of all 6 channels
• HD/SD-SDI, AC-3, and PCM or AES Status Indication LEDs
• Selected channel analog outputs on XLR connectors
• HD/SD-SDI group select 1-4 and subgroup select 1-2
• Headphone output
• Six 53-segment high resolution bargraph level meters
• Power indication LED
• Bargraph brightness adjust
4
© 2007 Wohler Technologies Inc. ALL rights reserved
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 1: General Features and Specifications
Applications
The ATSC/DVB-3/M is ideally suited for use in VTR bays, mobile production vehicles, teleconferencing installations, multimedia systems,
satellite links and cable TV facilities, and on-air radio studios. Designed and manufactured in the U.S., this unit is backed by a strong warranty
and a satisfaction guaranteed return policy.
General Specifications
AC-3 Input Specifications
Input Meter Dynamics:
Simultaneous VU (bar) and PPM (dot)
Peak Acoustic Output
(@ 2 ft.):
104 dB SPL
Response, Sixth Octave:
Power Output,
Ω):
RMS Each Side (4Ω
Ω):
RMS Bass (4Ω
70 Hz - 16 kHz ± 5 dB)
(-10 dB @ 40 Hz, 20 kHZ)
Input Impedance:
75Ω (ohm), unbalanced
Minimum Input level:
250 mV
Playback Mode:
“Line”
Input Connectors and
Impedance:
Less than 0.2% at any level below
limit threshold
Distortion, Acoustic:
BNC, female
PCM and AES/EBU Input Specifications
20 W transient / 11 W continuous
36 W transient / 20 W continuous
Distortion, Electrical:
Input Connector:
6% or less at worst case frequencies
above 120 Hz, including cabinet
resonance; typically less than 1.5%
Conversion Data
Width:
20 bit
Dynamic range:
95 dB
Frequency Response:
10 Hz - 20 kHz +/- 0.5 dB
< 0.005%
Hum and Noise:
Better than -70 dB below full output
Magnetic Shielding:
Less than 1 Gauss any adjacent surface
Analog Output
Distortion:
Input Connectors:
AES: 1x XLR Balanced and 1x BNC Unbal.
HD/SD-SDI: 1x Unbalanced BNC
Analog Outputs:
Output Connectors:
AES: 1x XLR-F Loop and 1x BNC Loop
HD/SD-SDI: 1x BNC Re-clocked
Selected Out: 2x XLR-M
Power Consumption
(Average Maximum):
60 W
AC Mains Input:
100-220VAC, 50-60 Hz
"ALL" Channel Summing
Assignments*:
Left Side =LFront+LSurr+Center
Right Side =RFront+RSurr+Center
BNC: 75 Ω (ohm), unbalanced
XLR: 110 Ω (ohm) balanced
.
balanced, line-level
(-20 dbfs=+4 dBu); minimum
load impedance:10k Ω (ohm)
HD/SD-SDI Input Specifications
* On special order, custom combinations of selected channels are
available; either in lieu of, or in addition to, the regular selections.
HD/SD-SDI Input Connector:
BNC, female
HD/SD-SDI Input Impedance:
75Ω (ohm), unbalanced
HD/SD-SDI Input Standards
Supported:
SMPTE 259M and SMPTE
292M
Audio Sampling Rate:
48 kHz
Note: See Section 3 (page 15) for additional technical information
and specifications.
Audio Response Curve
Physical Specifications
Weight:
18 lbs. (8.2 kg)
Dimensions (HxWxD):
3.5 x 19 x 12 inches
(89 x 483 x 298 mm)
+10
0
d
B
-10
-20
-30
20
50
100
200
500
1k
2k
5k
10k
20k
Hz
Typical 1/6 Octave Audio Response Curve
Units are designed to meet, at time of manufacture, all currently applicable product safety and EMC requirements, such as those of CE. 0 dbV ref. 0.775V
RMS. Features and specifications subject to improvement without notice.
© 2007 Wohler Technologies Inc. ALL rights reserved
5
Section 1: General Features and Specifications
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Installation
Mounting
NOTE: Be sure to set the Input Termination (accessed through the rear panel), BEFORE installing the unit into an enclosed rack
or console. See Item E, page 12 for setting information.
The unit should be mounted where convenient for operating persons, ideally at approximately ear level for best high frequency
response and eye level for best visual observation of the level meters. Its superior magnetic shielding eliminates concerns about
locating it adjacent to most types of CRT monitors, including even high-resolution color monitors.
Heat Dissipation
Heat dissipated by the speaker amps is conducted directly to the left side of the chassis; no special considerations for cooling are
necessary as long as the ambient temperature inside the rack area does not exceed approximately 40°C (104°F).
Sympathetic Vibration
Sympathetic vibration from other equipment (cables, etc.,) in the rack may be serious enough to interfere with the unit’s sound
quality out in the listening area. The use of thin card stock and/or felt or foam weather-stripping type materials between adjacent
vibrating surfaces, or tying up loose cables, etc., may be required to stop vibrations external to the unit.
Mechanical Bracing
Even though the unit is fairly heavy, the chassis is securely attached to the front panel at eight points along its surface, not just at
the four corners of the chassis ears. This feature will reduce or eliminate rear bracing requirements in many mobile/portable
applications. The weight of internal components is distributed fairly evenly around the unit.
Audio Connections
Connection of the audio feeds is straightforward. Please refer to the system interconnect block diagram on page 19 for clarification of
the general signal paths into and out of the ATSC/DVB-3/M unit.
Digital audio inputs are via either BNC or XLR connectors. BNC inputs are 75 Ω unbalanced; XLRs are 110 Ω balanced.
Care should be exercised to avoid mismatched cable types and other similar causes of undesired reflections in RF signal
systems. If severe enough, such reflections can result in corruption of the digital datastream. Recommended cable types are as
follows:
Recommended cable type for analog audio signals is: Belden 9451 or equivalent.
Recommended cable type for digital audio signals is: Belden 1800B or equivalent.
AC Power
The unit's AC mains connection is via a standard IEC inlet, with safety ground connected directly to the unit's chassis. The
universal AC input (100-240VAC, 50/60Hz) switching power supply is a self-resetting sealed type, with automatic over-voltage
and over-current shutdown. There is no user-replaceable fuse in either the primary or secondary circuit.
6
© 2007 Wohler Technologies Inc. ALL rights reserved
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 2
Operation
Front Panel Features
Rear Panel Features
© 2007 Wohler Technologies Inc. ALL rights reserved
7
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 2: Operation
Front Panel Features
Please refer to Figure-2a on the following page to familiarize yourself with the front panel features of the ATSC/DVB-3/M unit. The
following sections describe these features and are referenced, by number, to Figure-2a.
NOTE: Throughout this manual, the following terms are used to refer to Serial Digital (SDI) signals:
• SD-SDI = refers only to standard SDI (270 MB/s).
• HD-SDI = refers only to high-definition SDI (1.5 GB/s).
• HD/SD-SDI or SDI = refers to either standard SDI (SD-SDI, 270 MB/s) or high defintion SDI (HD-SDI, 1.5 GB/s)
1
Speakers
The internal speaker system is comprised of two mid-range tweeter speakers (left and right) and one woofer speaker (middle).
The two side channel speakers reproduce, in stereo, only the mid and high frequencies. Please note that the woofer speaker
(middle) is not a dedicated Center nor LFE speaker.
2
Speaker Select Switches (Left and Right)
Use the left switch to select any one of six selected channels for monitoring from the left speaker. Use the right switch to select
any one of six selected channels for monitoring from the right speaker.
Note: These two switches are only functional when the All/Selected Switch (Item 7) is in the SELECTED position. These two
switches are NOT functional when the All/Selected Switch is in the ALL position.
3
Speaker Select Disabled Indication LEDs (Left and Right)
When the All/Selected Switch (Item 7) is in the ALL position (thus disabling the Speaker Monitor Select Switches) both of
these LEDs will glow RED.
4
Audio Level Meter LED Bargraph Displays (1-6)
Audio levels for source channels 1 through 6 are displayed via these six high-resolution 53-segment LED bargraph display level
meters (three on the left side of the front panel; three on the right side). Dynamic range for these meters is 65 dB and they are
able to display signal levels using both PPM and VU standards. Each meter is labeled according to the standard Surround
Sound nomenclature (left front, right front, center, low frequency effects, left surround, and right surround). See page 18 for more
information about these level meters.
5
Bargraph Brightness Trim Pot (Left and Right)
These two trim pots are recessed into the front panel and can be accessed using a small screwdriver. Turning either trim pot
clockwise will increase the relative brightness of the associated bargraph display LED segments. The left trimpot affects the left
three bargraph displays (1-3); the right trim pot affects the right three bargraph displays (4-6).
6
Input Source Select Switch
This 2-position toggle switch allows the operator to choose between two possible input sources (1-AES or 2-SDI) for monitoring
through the unit. Choosing 1-AES selects the AC-3 or PCM/AES signals entering the Source 1 connectors on the rear panel
(See Items C and D, page 12). Choosing 2-SDI selects an AC-3 or PCM/AES source that is de-embedded from the HD/SD-SDI
signal entering the Source 2 BNC connector on the rear panel (see Item F, page 12).
7
All/Selected Switch
When this 2-position toggle switch in in the ALL position, a stereo mixdown of the five full channels is applied to the speaker
amps (the LFE channel is excluded). In this posiotion both the left and right Speaker Select Switches (Item 2) are disabled and
the Speaker Select Disabled Indication LEDs (Item 3) will glow RED.
When this switch is in the SELECTED position, channel selection defaults to the settings as selected by the left and right
Speaker Select Switches (Item 2) and the left and right Speaker Select Disabled Indication LEDs (Item 3) will be unlit.
8
9
SDI Group Select Switch
This 4-position rotary switch allows the operator to choose HD/SD-SDI GROUP 1, 2, 3, or 4 for monitoring. The Subgroup (1
or 2) of each HD/SD-SDI GROUP is selected using the SDI Subgroup Select Switch (Item 17, page 10).
Note that the Input Source Select Switch (Item 6) must be set to 2-SDI in order for the selected HD/SD-SDI signals to be actively
monitored.
Volume Control Pot
This controls the loudness of the audio reproduced by the internal speakers or connected headphone. Clock-wise rotation of
this control increases the loudness of the monitored audio.
8
© 2007 Wohler Technologies Inc. ALL rights reserved
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 2: Operation
Figure-2a: Front Panel Features
© 2007 Wohler Technologies Inc. ALL rights reserved
9
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 2: Operation
Front Panel Features
10
Power Indication LED
This LED signals the operating condition of the power supply. The LED glows GREEN to indicate the unit is connected to
mains power and an operation voltage is present.
11 Phase Indication LEDs
These three LEDs indicate the instantaneous and average phase (polarity) conditions between the source(s) assigned to
the left speaker channel and the source(s) assigned to the right speaker channel. The larger LED labeled AVG indicates
the average phase condition between the left and right speaker channels. The two smaller LEDs labeled IN and OUT
indicate the instantaneous phase relationships. Indication is as follows:
• The small left LED (IN) glows (or blinks) GREEN for in-phase signals.
• The small right LED (OUT) glows (or blinks) AMBER for out-of-phase signals.
• The large center AVG LED indicates the average phase condition by glowing GREEN for in-phase signals, or RED for
out-of-phase signals.
In general, observing the AVG LED alone is sufficient for proper phase monitoring. While it is normal for stereo signals
to contain some intermittant instantaneous out-of-phase and in-phase conditions (IN and OUT LEDs), a steady RED
glow of the AVG LED indicates an out-of-phase alarm condition.
12 SDI Signal Status Indication LED
This LED will indicate the status of any SDI signal entering Source 2 regardless of any monitor selection settings. This LED
shows the following conditions:
• OFF:
No valid HD/SD-SDI signal is present.
• GREEN: A valid HD/SD-SDI signal is present.
• RED:
The HD/SD-SDI signal is not properly received.
13 Headphone Jack
Select the headphone audio sources as you would for the internal speakers. When you plug in headphones, the speakers will
mute. This jack accepts a standard 1/4” phone type stereo plug.
14 AC-3 and PCM Input Status Indication LEDs
These two green LEDs indicate which kind of signal is being received at the Source 1 inputs. When an AC-3 signal is being
monitored from Source 1 inputs, the left AC-3 LED will glow GREEN. When a PCM or standard AES/EBU signal is being
monitored from the Source 1 inputs, the right PCM LED will glow GREEN.
15 Pro-16 Selection Switch and Indication LED
In the event that you are processing two different Dolby Digital Pro-16 data streams it is possible to select between the two
with this toggle switch. The LED will glow AMBER if such signals are present. In the absence of such data streams, the LED
will not be lit and the switch will be nonfunctional.
16 Balance Control Pot
This control pans the volume balance between the left and right speakers.
17 SDI Subgroup Select Switch (1 or 2)
This 2-position toggle switch allows the operator to choose whether the unit will monitor Subgroup 1 (channels 1 and 2) or
Subgroup 2 (channels 3 and 4) of the chosen HD/SD-SDI Group (1, 2, 3, or 4) as selected by the SDI Group Select Switch (Item
8, page 8). Subgroup selection chooses the channels to be monitored from the selected SDI Group as follows:
Subgroup 1 = Channels 1 and 2 Subgroup 2 = Channels 3 and 4
Note that the Input Source Select Switch (Item 6) must be set to 2-SDI in order for the selected HD/SD-SDI signals to be actively
monitored.
10
© 2007 Wohler Technologies Inc. ALL rights reserved
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 2: Operation
Figure-2a: Front Panel Features
© 2007 Wohler Technologies Inc. ALL rights reserved
11
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 2: Operation
Rear Panel Features
Please refer to Figure-2b on the following page to familiarize yourself with the rear panel features of the ATSC/DVB-3/M unit. The
following sections describe these features and are referenced, by letter, to Figure-2b.
NOTE: Throughout this manual, the following terms are used to refer to Serial Digital (SDI) signals:
• SD-SDI = refers only to standard SDI (270 MB/s).
• HD-SDI = refers only to high-definition SDI (1.5 GB/s).
• HD/SD-SDI or SDI = refers to either standard SDI (SD-SDI, 270 MB/s) or high defintion SDI (HD-SDI, 1.5 GB/s)
A
Power Connector
Attach the supplied IEC-320 power cord between this connector and mains power (100 - 240VAC nominal, 50/60 Hz).
The front panel Power Indication LED (Item 10, page 10) will glow GREEN to indicate operating voltages are present.
B
Option DIP Switch Module
This DIP switch is reserved for possible options still to be determined. You may disregard its settings.
C
Source 1 - AC-3 Balanced Input and Loop-Through Connectors
The BALANCED IN connector (3-pin female XLR) accepts either AC-3 (Dolby Digital®) or standard PCM or AES signals
and is configured for balanced 110 Ω impedance connections. See diagram below for pinout information.
The BALANCED LOOP connector (3-pin male XLR) outputs a copy of the signal entering either the BALANCED IN or
UNBAL IN (Item D) input connector (whichever one is used). See diagram below for pinout information.
NOTE: Refer to the Input Source Select Switch description (Item 6, page 8) for how to select this input for monitoring.
Pin-2
High (+)
Pin-1
Gnd
(Shield)
Pin-1
Gnd
(Shield)
Pin-2
High (+)
XLR, 3-Pin Male
OUTPUT Pinout
XLR, 3-Pin Female
INPUT Pinout
Pin-3
Low (-)
D
Pin-3
Low (-)
Source 1 - AC-3 Unbalanced Input and Loop-Through Connectors
The UNBAL IN connector (female BNC) accepts either AC-3 (Dolby Digital®) or standard PCM or AES signals and is
configured for unbalanced 75 Ω impedance connections.
The UNBAL LOOP connector (female BNC) outputs a copy of the signal entering either the BALANCED IN (Item C) or
UNBAL IN input connector (whichever one is used).
NOTE: Refer to the Input Source Select Switch description (Item 6, page 8) for how to select this input for monitoring.
E
Termination DIP Switch Module
In the event that signals entering the Source 1 inputs (Item C or D) are connected to downstream equipment, then DIP
switch section 1 of this module should be set to UNTERMINATED (UP). If there is no connection to downstream
equipment, then section 1 should be set to TERMINATED (DOWN).
NOTE: Section 2 of this DIP switch is not functional.
F
Source 2 - HD/SD-SDI Input and Output Connectors
The (HD)SD-SDI IN connector (female BNC) accepts either standard SD-SDI audio signals (270 MB/s) or high definition
HD-SDI (1.5 GB/s).
Refer to the Input Source Select Switch description (Item 6, page 8) for how to select this input for monitoring. Refer to
the SDI Group Select Switch (Item 8, page 8) and SDI Subgroup Select Switch (Item 17, page 10) descriptions for how
to select HD/SD-SDI groups and sub-groups for monitoring.
The (HD)SD-SDI OUT connector (female BNC) outputs a re-clocked (regenerated) HD/SD-SDI signal copy derived from
the HD/SD-SDI input. This output functions regardless of other selection settings. This feature enables output of the reclocked HD/SD-SDI signal independant of the units other monitoring functions (as long as a valid HD/SD-SDI signal is
present at the input).
12
© 2007 Wohler Technologies Inc. ALL rights reserved
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 2: Operation
Figure-2b: Rear Panel Features
© 2007 Wohler Technologies Inc. ALL rights reserved
13
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Rear Panel Features
G
Selected Output (Analog) Connectors (Chan.A/Left and Chan.B/Right)
The two SELECTED OUTPUT (ANALOG) connectors (3-pin male XLR) are analog outputs of the input signals as
selected for active monitoring through the left and right speakers (or headphones). The left CH.A(L) connector outputs
the left speaker channel (channel A) and the right CH.B(R) connector outputs the right speaker channel (channel B).
Both connectors are configured for low impedance connections and the output signals are at unity gain with the input
level and are not affected by the units Volume and Balance controls or Headphone Mute feature. For XLR connector
pinout information, see the diagram under Item C, page 12.
H
OPT Mode Select Switch
This recessed 10-position rotary switch sets the mode of operation. When set to position 0, the unit is configured to download
programing information. When set to positions 1 through 9, the unit will operate normally. See below for setting information.
I
RS232 Connector
This DB-9 connector is used for downloading programming, setup, and diagnostic information into and out of the
919212 audio de-embedder.
14
© 2007 Wohler Technologies Inc. ALL rights reserved
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 3
Technical Information
General Technical Observations
Level Meter Specifications
ATSC/DVB-3/M Interconnect Block Diagram
NOTE:
PCB layout and schematic support documentation is available upon request.
© 2007 Wohler Technologies Inc. ALL rights reserved
15
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 3: Technical Information
General Technical Observations
General Mechanical Observations
Elimination of cabinet and component sympathetic vibrations (resonances) requires considerable attention to mechanical details.
Because of this, and the physical constraints of the speaker’s acoustic enclosures, even minor changes to any of the mechanical
details of the unit can seriously impair its acoustic performance. This especially applies to the speaker baffles. If mechanical
work on the unit is necessary, be sure to make adequate notes to permit accurate reassembly.
Unfortunately, the unusual and wholly proprietary method of magnetic shielding is usually degraded slightly by any disassembly of
the unit, except removal of the rear panel. Almost any maintenance or repair will require removal of the cover. If an immediately
adjacent video monitor shows magnetic interference after reassembly of the unit, it must be returned to the factory to restore the
shielding completely.
General Audio Circuitry Observations
Since a single-sided power supply is used, all amplifier sections are “biased” with a 1/2 supply reference, so all opamp signal
terminals on the main board should have a DC level of +12V, +/-0.7V. Signal inputs to the main audio board from any of the input
select circuits are via the balanced input stage, in lieu of the XLR analog inputs on the basic unit. Signal feed points for level
meters and the phase indicator are immediately after the input stage, and before the volume control section. The signal pick-off
for the headphones is after the volume and balance controls. Speaker muting is controlled by circuitry that senses connection of
headphones to the jack.
The power amps are attached to an aluminum heatsink plate (which is also connected to the circuit common for these devices).
The heatsink plate forms an operational module separate from the chassis, which allows access to the solder side of the circuit
board while power is applied to the circuitry. To avoid thermal shutdown of the power amp(s), they should NOT be operated
without their tabs being fastened to the heatsink plate.
Variations in the frequency response of different production runs of drivers sometimes requires minor adjustments in the
equalization/crossover components in individual runs of units. Some of these components may have values slightly different than
those indicated in the schematic, which are the nominal ones. If any of the drivers (speakers) are replaced, it may be helpful to
change some of these components to achieve maximum flatness of response.
The operating threshold of the woofer limiter is critical to both satisfactory reproduction of musical transients and preventing
damage to, or destruction of, the speaker itself. The side speaker output limiter circuits are similarly important, though not as
critically adjusted.
The woofer power amps are arranged in a bridge configuration; care must be taken to avoid letting EITHER speaker terminal
contact the chassis (common) OR THE GROUNDED LEAD OF ANY TEST EQUIPMENT so as not to short out the power amps.
The side speaker outputs are single-ended, so these precautions are not necessary for them.
16
© 2007 Wohler Technologies Inc. ALL rights reserved
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 3: Technical Information
Level Meter Specifications
Description
The 53-segment type of tri-color LED bargraph display has a total length of 2.24" (56.8 mm) and uses relatively small segments. This
high resolution segment size is easy to accurately visually monitor for distances up to six feet (1.8 meters). Segment size is 0.158" (4
mm) x 0.04" (1 mm). Segment pitch is 0.039" (0.99 mm).
Each LED bargraph display section visually indicates the dynamic changes within the audio signal source(s) being monitored. All
bargraph LED segments are of the tri-color type (green, amber, red). Ballistics for these meters are factory set to display a single
floating PPM 'dot' (continuous decay of 20 dB in 1.5 seconds) above a VU bar; each segment's color being fixed according to its position
on the scale. Level gain is factory set at +4 dBu. Dynamic range for these meters is 65 dB.
Scales
Please refer to the figure below for an illustration showing the standard scale for the 53-segment bargraph display used in the ATSC/
DVB-3/M digital audio monitor. Custom variations of this scale are also available by special order.
0
2
4
7
10
13
16
18
20
22
25
28
31
34
38
42
46
51
56
66
0
2
4
7
10
13
16
18
20
22
25
28
31
34
38
42
46
51
56
66
LED Bargraph Level Meter Specifications
Level meter type:
LED bargraph
Segment quantity:
53
Level Meter Scale:
0 to -66 dB
Dynamic Range:
65 dB
Midscale Resolution:
1 dB
Bargraph Length:
2.22" (56.4 mm)
LED segment size:
0.14" x 0.028" (3.57 x 0.7 mm)
LED segment pitch:
0.041" (1.05 mm)
Segment display color:
Tri-color (red, amber, green)
Peak emission wavelength:
Green: 570 nm, Red: 630 nm
Segment brighness, (If = 20 mA):
3.5 mcd
Segment brightness, uniformity:
<10% difference between segments
Adjacent segment "Off" brightness:
<1% of brightness of active segment
© 2007 Wohler Technologies Inc. ALL rights reserved
17
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Section 3: Technical Information
ATSC/DVB-3/M Interconnect Block Diagram
18
© 2007 Wohler Technologies Inc. ALL rights reserved
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
NOTES:
NOTE:
PCB layout and schematic support documentation is available upon request.
© 2007 Wohler Technologies Inc. ALL rights reserved
19
ATSC/DVB-3/M User Manual P/N 821650 Rev-B
Wohler Technologies, Inc.
Wohler
Technologies, Inc.
31055 Huntwood Avenue
31055 Huntwood Avenue
Hayward, CA 94544
Hayward, CA 94544
Phone: (510) 589-5676
Phone: (510) 870-0810 Fax: (510) 870-0811
Fax: (510) 870-0811
US Toll-Free: 1-888-596-4537
US Toll-Free: 1-888-596-4537
www.wohler.com support@wohler.com
web: www.wohler.com
e-mail: support@wohler.com
20
© 2007 Wohler Technologies Inc. ALL rights reserved
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