DR66
6 In 6 OUT AUDIO SYSTEM
24-Bit Digital
Mix Processor
SERVICE
MANUAL
PUBLICATION AP3137
HOW TO USE THIS MANUAL
This service manual is published in two sections:
Section A:
contains the INSTALLATION / USER GUIDE
which includes details of INSTALLATION,
CALIBRATION and OPERATION for the DR6
66.
Section B:
contains the SERVICE INFORMATION which
includes details of SPARE PARTS &
ASSEMBLIES and CIRCUIT BOARD DIAGRAMS
for the DR6
66.
copyright  1998 ALLEN & HEATH. All rights reserved.
Publication..........AP3137 Issue 1.
DR66 SERVICE MANUAL
SECTION A
A
A
DR66 INSTALLATION / USER GUIDE
CAUTION
Refer all installation, calibration and
service work to qualified service
personnel.
DR66 SERVICE MANUAL
SECTION B
B
DR66 SERVICE INFORMATION
CAUTION
Refer all installation, calibration and
service work to qualified service
personnel.
Warning to the Service Engineer
Allen & Heath warns that any unauthorised changes or
modifications to the DR66 unit may invalidate the legal
compliance of the unit and could void the user’s authority
to operate the equipment.
DR66 SERVICE MANUAL
2
Section B
CONTENTS
INTRODUCTION & WARNINGS......................................................................................... 3-4
ORDERING A DR6
66 UNIT, OPTIONS & DOCUMENTATION.............................................. 5
ORDERING SPARE ASSEMBLIES & SPARE PARTS ........................................................ 6-7
BLOCK DIAGRAM .............................................................................................................. 8
FRONT PANEL CIRCUIT BOARD COMPONENT IDENT ................................................... AG3131
FRONT PANEL CIRCUIT DIAGRAM .................................................................................. C3131
CONVERTER CIRCUIT BOARD COMPONENT IDENT...................................................... AG3135
CONVERTER CIRCUIT DIAGRAM sheet 2 of 9 (line inputs 1 to 4)..................................... C3135
CONVERTER CIRCUIT DIAGRAM sheet 3 of 9 (mic inputs 1 & 2) ..................................... C3135
CONVERTER CIRCUIT DIAGRAM sheet 4 of 9 (balanced line outputs 1 & 2) .................... C3135
CONVERTER CIRCUIT DIAGRAM sheet 5 of 9 (balanced line outputs 3 & 4) .................... C3135
CONVERTER CIRCUIT DIAGRAM sheet 6 of 9 (balanced line outputs 5 & 6) .................... C3135
CONVERTER CIRCUIT DIAGRAM sheet 7 of 9 (digital circuits & connectors).................... C3135
CONVERTER CIRCUIT DIAGRAM sheet 8 of 9 (codec circuits) ......................................... C3135
CONVERTER CIRCUIT DIAGRAM sheet 9 of 9 (power supply) .......................................... C3135
MICROPROCESSOR CPU CIRCUIT BOARD COMPONENT IDENT ................................. AG2604
MICROPROCESSOR CPU CIRCUIT DIAGRAM sheet 2 of 6 (interface) ............................ C2604
MICROPROCESSOR CPU CIRCUIT DIAGRAM sheet 3 of 6 (CPU & memory) ................. C2604
MICROPROCESSOR CPU CIRCUIT DIAGRAM sheet 4 of 6 (processing engine #1)......... C2604
MICROPROCESSOR CPU CIRCUIT DIAGRAM sheet 5 of 6 (processing engine #2)......... C2604
MICROPROCESSOR CPU CIRCUIT DIAGRAM sheet 6 of 6 (expander connectors) ......... C2604
Refer to SECTION A for information on installation, calibration and
operation of the DR66.
DR66 SERVICE MANUAL
Section B
3
INTRODUCTION
The information presented in this section of the manual is intended for competent technical
personnel to carry out service and product support for the DR66. We assume that the reader is
familiar with the related electronic theory and audio terminology, and is able to carry out basic
servicing, fault-finding and repair of digital audio equipment of this type. Service personnel should
also be familiar with audio systems, mains earthing and power requirements, as well as handling
precautions.
For information on the installation, operation and application of the DR66 please refer to section
A of this manual.
Whilst we believe the information in this manual to be reliable we do not assume responsibility for
inaccuracies. We also reserve the right to make changes in the interest of further product
development.
SERVICE AND TECHNICAL SUPPORT
Under normal operating conditions the DR66 does not require user maintenance or internal
calibration. Any service work required should be carried out by qualified technical personnel
only.
We are able to offer further product support through our worldwide distribution network. To
help us provide an efficient service please quote the unit serial number, the date and place of
purchase in any communication regarding this product.
SAFETY WARNING
Mains electricity is dangerous and can kill. Mains voltage is present within the
unit. Except for installation and calibration, do not remove any covers with power
connected. Do not carry out any work within the unit while it is powered. High
voltage components are insulated for safety but should not be touched with power
applied. The mains voltage setting is indicated on the AC mains input socket on
the rear panel. Check that this matches your local supply. Check your mains
wiring and earthing before switching on.
DO NOT REMOVE THE MAINS EARTH
CONNECTION!
The chassis is always connected to mains earth. Audio 0V connects to the
chassis internally. Should problems be encountered with ground loops, operate
the audio ground lift switches on other equipment connected to the unit or
disconnect the cable screens at one end. Refer to the section on ‘EARTHING’ in
the User Guide.
DR66 SERVICE MANUAL
4
Section B
WARNING
There is danger of explosion if the battery is incorrectly replaced.
Replace the battery with an Allen & Heath recommended part. Using a different
battery, recharging or disassembling the battery may present a danger due to fire
or explosion.
Dispose of used batteries promptly according to the manufacturer’s instructions.
Keep all batteries away from children.
IMPORTANT STATIC ELECTRICITY
PRECAUTIONS
Many of the components in the DR66 are extremely sensitive to static electricity.
The following procedures reduce the possibility of damaging components:
1. Before handling any components or touching anything inside the unit,
discharge your body’s static electric charge by touching a grounded (earthed)
surface. Wear a grounding wrist strap if one is available.
2. Do not remove parts from their antistatic containers or bags until you are ready
to install them. When removing circuit boards (PCBs) or chips from a unit,
immediately place them in an antistatic bag.
3. When handling PCBs, hold them by their edges and avoid touching the
circuitry.
4. Do not slide PCBs or ICs over any surface.
5. Avoid having plastic, vinyl and foam in your work area.
6. Limiting your movements during service work reduces static electricity.
DR66 SERVICE MANUAL
Section B
5
ORDERING A DR66 UNIT
To order a new unit please specify the model number and AC mains voltage required.
MODEL
DESCRIPTION
ORDER CODE
DR66
6 inputs 6 outputs
DR66/volts
ORDERING AN OPTION
To order an option please specify the model number.
DESCRIPTION
ORDER CODE
DR128/66 DSPD delay expander card
DR1-DSPD
DR66 DSP expander card
DR66-DSPX
DR66 SYSNET option
DR66-SNET
MANUALS, SOFTWARE AND SUPPORT DOCUMENTATION
DESCRIPTION
ORDER CODE
DR66 User Guide
AP3138
DR66 Service Manual
AP3137
DR66 Brochure
AP3205
DR66 WinDR Disk (1 of 3)
002-272
DR66 WinDR Disk (2 of 3)
002-273
DR66 WinDR Disk (3 of 3)
002-362
SERVICE TOOLS
The tools required to service the DR66 range of products are standard to an electronics service
workshop and are easily obtainable. The following items are necessary for disassembly and
service access:
1-point Crosshead screwdriver (M3, 4AB)
AT0004
2-point Crosshead screwdriver (M4, 6AB)
AT0002
5mm AF Nutdriver (D type mountings)
DR66 SERVICE MANUAL
6
Section B
ORDERING AN ASSEMBLY
The following assemblies for the DR66 are supplied fully tested. Please quote the description and
order code for the part required.
Printed circuit (PCB) assemblies:
DESCRIPTION
ORDER CODE
DR1 CPU PCB assembly
002-184
DR66 Converter PCB assembly
002-298
Front Panel PCB assembly
002-300
IDC connector harnesses:
DESCRIPTION
ORDER CODE
26 way Mic / Line harness
AL2712
9 way RS232 harness
AL3198
16 way LCD display harness
AL3144
40 way Audio harness
AL3142
9 way CPU power harness
AL3141
26 way Front Panel harness
AL3143
Ordering a spares kit
It is recommended that the spares kit order code 002-293 is held and maintained by the service
agent to enable in-field service repairs to the DR66 independent of the ALLEN & HEATH
factory. Commonly available items such as resistors, capacitors, tools and soldering equipment
are not included. The contents of the kit are listed below. Individual spare parts may be ordered.
Please quote the description and order code for the part required.
DESCRIPTION
ORDER CODE
QTY
Fixings:
Fastfeet 20mm
Joint Block Nylon
M3 Half Nut
Nylock Nut M3
Pillar Snap-in 6mm Nylon
Pillar Snap-in M2.5 x 8mm
Pillar Support 6.4mm Nylon
Screw 4 x 5/16 Poly Pan Pozi Black
Screw 4AB x ¼ Pan Pozi Plated
Screw 4AB x 5/16 CSK Pozi Black
Screw 4UNC Hex D-Type
Screw M3 x 10mm Pan Pozi Black
Screw M3 x 12 Pan Pozi Black
Screw M3 x 4mm Pan Pozi Black
Screw M6 x 30mm CSK Allen Black
Washer M3 Shakeproof
DR66 SERVICE MANUAL
AK0102
AB0253
AB0094
AB0102
AB2233
AB2774
AB2171
AB2810
AB0252
AB0059
AB2189
AB0076
AB0078
AB0233
AB2327
AB0244
5
5
5
10
10
5
5
10
5
5
5
5
5
10
5
5
Section B
7
Potentiometers, switches and connectors:
Button 12.5mm Square Black
Button Round Black
Button Round Grey
Phono Dual PCB Mount
Pot 9mm 5KRD
Switch 2PCO Momentary
XLR 3 Pin Female PCB Mount
XLR 3 Pin Male PCB Mount
AJ0348
AJ2887
AJ2888
AL0556
AI8059
AL8058
AL2414
AL2413
10
5
5
4
2
5
5
5
AE2749
AE2755
AE0345
AE0221
AE2742
AE0046
AE2748
AE2754
AE8069
AE0020
5
3
2
10
1
5
5
10
5
5
AE2947
AE0308
AE3155
AE2815
AM3153
AA0693
AL0311
AL0349
AL0297
AH0205
AH0206
AH0323
AM3134
5
5
5
1
5
5
5
5
5
-
002-294
AA3145
AA3150-LR
AE2734
AF3107
AL0334
AM2970
AP2837
5
10
5
1
LEDs and Semiconductors:
IC CMOS 74HC165
IC CMOS 74HC4094
IC CMOS 74HCO3 4NAND2
IC NE5532N OP-AMP
IC RS232 MAX202CPE
IC TL072 OP-AMP
IC TLP521-4A OPTO QUAD
LED 5 x 2mm Tri-colour
Transistor 2SB737 PNP
Transistor BC549 NPN
POWER SUPPLY:
Diode SBYV28-100 UltraFast 3.5A
IC Regulator 7805
IC Regulator 7818
IC Regulator LM2576T-5.0
Inductor 220uH 3A S/SWITCH
Insulating kit TO220
Fuse 20mm T2.5A (Battery DC supply)
Mains Fuse 20mm T315mA (UK)
Mains Fuse 20mm T630mA (UK, EU)
Mains lead IEC-2pin EURO
Mains lead IEC-3pin UK
Mains lead IEC-3pin US (C33)
Transformer 25VA
Miscellaneous:
DR66 Packing assembly
DR66 Acrylic Fascia
Rack Mounting brackets (per pair)
Front panel LCD display
EMI filter 470pF 100V
Jumper socket
Inductor 150u 280mA
Battery 3V 180mAh PCBV
DR66 SERVICE MANUAL
8
DR66 BLOCK DIAGRAM
DR66 SERVICE MANUAL
Section B