Arcam HDA PA720 User manual

SERVICE MANUAL
POWER AMPLIFIER
PA720
ISSUE A

EN-2
Revision History
Issue A - Initial release

EN-3
Contents
Safety Summary EN-4
Safety Guidelines EN-5
Electrostatic Discharge (ESD) Precautions EN-7
General Information EN-8
PA720 Specications EN-9
Functional Verication and Test Procedure EN-10
Troubleshooting EN-12
Theory of Operation EN-13
Power Amplier PCB - L281 EN-13
Pre-amplier PCB - L282 EN-13
Mains Input PCB - L283 EN-13
Lifter PCB - L284 EN-13
These service instructions are only intended for use by
qualied personnel. Do not perform any servicing other than
that contained in these instructions unless qualied to do so.
Refer to the Safety Guidelines prior to performing any service
L281 Power Amplier PCB Issue 3 EN-14
L282 Pre-amp PCB Issue 2 EN-36
L283 PSU PCB Issue 1 EN-50
L284 Lifter PCB Issue 1 EN-54
L285 Front Panel PCB Issue 1 EN-59
Overall Dimensions EN-62
Exploded Drawings EN-64

EN-4
Safety Summary
The following general safety precautions must be observed during all phases of operation, service, and repair of this unit. Failure to comply with these precautions or with specic warnings elsewhere in these instructions violates
manufacturer safety standards and intended use of this unit. Harman Luxury Audio Group assumes no liability for failure to comply with these requirements.
DO NOT OPERATE IN AN EXPLOSIVE ATMOSPHERE
Do not operate the unit in the presence of ammable gasses or fumes. Operation of any electrical instrument in such an environment constitutes a denite safety hazard.
KEEP AWAY FROM LIVE CIRCUITS
Operating personnel must not remove unit covers. Qualied maintenance personnel must make component replacements and internal adjustments. To avoid personal injuries, always disconnect power and discharge circuits before
touching them.
DO NOT SERVICE OR ADJUST ALONE
Do not attempt internal service or adjustment unless another person capable of rendering rst-aid resuscitation is present.
DO NOT SUBSTITUTE PARTS OR MODIFY INSTRUMENT
Because of the danger of introducing additional hazards, do not install substitute parts or perform any unauthorized modication to the unit.
DANGEROUS PROCEDURE WARNINGS
Warnings such as the example shown below precede potentially dangerous procedures throughout this document. Instructions contained in warnings must be followed.
WARNING
Dangerous voltages capable of causing death are present in this unit. Use extreme caution when handling, testing, or adjusting.

EN-5
Safety Guidelines
Read these instructions.
Keep these instructions.
Heed all warnings.
Follow all instructions.
Do not use this apparatus near water.
Clean only with dry cloth.
Do not block any ventilation openings. Install in
accordance with the manufacturer’s instructions.
Do not install near any heat sources such as radiators,
heat registers, stoves, or other apparatus (including
ampliers) that produce heat.
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 t into your outlet, consult an electrician for
replacement of the obsolete outlet.
Protect the power cord from being walked on or
pinched particularly at plugs, convenience receptacles,
and the point where they exit from the apparatus.
Only use attachments/accessories specied by the
manufacturer.
Use only with the cart, stand, tripod, bracket, or
table specied 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.
Unplug this apparatus during lightning
storms or when unused for long periods
of time.
Refer all servicing to qualied service personnel.
Servicing is required when the apparatus has been
damaged in any way, such as 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.
Object or liquid entry
WARNING – Take care that objects do not fall and liquids
are not spilled into the enclosure through any openings.
The equipment shall not be exposed to dripping or
splashing. Liquid-lled objects such as vases should not
be placed on the equipment.
Climate
The equipment has been designed for use in moderate
climates and in domestic situations.
Cleaning
Unplug the unit from the mains supply before cleaning.
The case should normally only require a wipe with a
soft, lint-free cloth. Do not use chemical solvents for
cleaning.
We do not advise the use of furniture cleaning sprays
or polishes as they can cause permanent white marks.
Power sources
Only connect the equipment to a power supply of
the type described in the operating instructions or as
marked on the equipment.
The primary method of isolating the equipment from
the mains supply is to remove the mains plug. The
equipment must be installed in a manner that makes
disconnection possible.
Abnormal smell
If an abnormal smell or smoke is detected from the
equipment, turn the power o immediately and unplug
the equipment from the wall outlet. Contact your dealer
and do not reconnect the equipment.
Damage requiring service
The equipment should be serviced by qualied service
personnel when:
The power-supply cord or the plug has been damaged,
or
Objects have fallen, or liquid has spilled into the
equipment, or
The equipment has been exposed to rain, or
The equipment does not appear to operate normally or
exhibits a marked change in performance, or
The equipment has been dropped or the enclosure
damaged.
CAUTION: To reduce the risk of electric shock, do
not remove cover (or back). No user serviceable
parts inside. Refer servicing to qualied service
personnel.
WARNING: To reduce the risk of re or electric shock,
do not expose this apparatus to rain or moisture.
The lightning ash with an arrowhead
symbol within an equilateral triangle, is
intended to alert the user to the presence of
uninsulated ‘dangerous voltage’ within the
product’s enclosure that may be of sucient magnitude
to constitute a risk of electric shock to persons.
The exclamation point within an equilateral
triangle is intended to alert the user to the
presence of important operating and
maintenance (servicing) instructions in the
literature accompanying the product.
CAUTION: In Canada and the USA, to prevent
electric shock, match the wide blade of the plug to
the wide slot in the socket and insert the plug fully
into the socket.
Class II product
This equipment is a Class II or double insulated electrical
appliance. It has been designed in such a way that it
does not require a safety connection to electrical earth
(“ground” in the U.S.)
Warning
Mains plug/appliance coupler is used to disconnect
device and it shall remain readily operable.
Safety Compliance
This equipment has been designed to meet the IEC/EN
62368-1 international electrical safety standard.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
This device may not cause harmful interference, and
This device must accept any interference received,
including interference that may cause undesired
operation.
The building installation shall be regarded as providing
protection in accordance with the rating of the wall
socket outlet.
Caution on installation
For proper heat dispersal, do not install this unit in a
conned space, such as a bookcase or similar enclosure.
More than 0.3m (12in) is recommended.
Do not place any other equipment on this unit.
zz
z
Wall
z

EN-6
FCC Information(for US customers)
This product complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
This device may not cause harmful interference, and
This device must accept any interference received,
including interference that may cause undesired
operation.
IMPORTANT NOTICE: DO NOT MODIFY THIS
PRODUCT
This product, when installed as indicated in the
instructions contained in this manual, meets FCC
requirements. Modication not expressly approved by
ARCAM may void your authority, granted by the FCC, to
use the product.
NOTE
This product has been tested and found to comply with
the limits for a Class B digital device, pursuant to Part 15
of the FCC Rules. These limits are designed to provide
reasonable protection against harmful interference in a
residential installation.
This product generates, uses and can radiate radio
frequency energy and, if not installed and used in
accordance with the instructions, may cause harmful
interference to radio communications. However, there
is no guarantee that interference will not occur in a
particular installation. If this product does cause harmful
interference to radio or television reception, which can
be determined by turning the product OFF and ON, the
user is encouraged to try to correct the interference by
one or more of the following measures:
Reorient or relocate the receiving antenna.
Increase the separation between the equipment and
receiver.
Connect the product into an outlet on a circuit dierent
from that to which the receiver is connected.
Consult the local retailer authorized to distribute this
type of product or an experienced radio/TV technician
for help
Safety Information (for European customers)
Avoid high temperatures. Allow for sucient heat
dispersion when installed in a rack.
Handle the power cord carefully. Hold the plug when
unplugging the cord.
Keep the unit free from moisture, water, and dust.
Unplug the power cord when not using the unit for
long periods of time.
Do not obstruct the ventilation holes.
Do not let foreign objects into the unit.
Do not let insecticides, benzene, and thinner come in
contact with the unit.
Never disassemble or modify the unit in any way.
Ventilation should not be impeded by covering the
ventilation openings with items, such as newspapers,
tablecloths or curtains.
Naked ame sources such as lighted candles should not
be placed on the unit.
Observe and follow local regulations regarding battery
disposal.
Do not expose the unit to dripping or splashing uids.
Do not place objects lled with liquids, such as vases,
on the unit.
Do not handle the mains cord with wet hands.
When the switch is in the OFF position, the equipment
is not completely switched o from MAINS.
The equipment shall be installed near the power supply
so that the power supply is easily accessible.
A note about recycling
This product’s packaging materials are recyclable
and can be reused. Please dispose of any materials in
accordance with the local recycling regulations.
When discarding the unit, comply with local rules or
regulations.
Batteries should never be thrown away or incinerated
but disposed of in accordance with the local regulations
concerning battery disposal.
This product and the supplied accessories, excluding
the batteries, constitute the applicable product
according to the WEEE directive
Correct disposal of this product
These markings indicate that this product should not be
disposed with other household waste throughout the
EU.
To prevent possible harm to the environment or
human health from uncontrolled waste disposal and
to conserve material resources, this product should be
recycled responsibly.
To dispose of your product, please use your local return
and collection systems or contact the retailer where the
product was purchased.
Pb

EN-7EN-7
Keep circuit boards in their original packing until ready for use.
Avoid having plastic, vinyl or styrofoam in the working area.
Wear an anti-static wrist strap.
Discharge personal static before handling circuit boards.
Remove and insert circuit boards with care
When removing circuit boards, handle only by non-conductive surfaces. Never touch open-edge
connectors except at a static free work station.
Minimize handling of circuit boards.
Handle each circuit board by its edges.
Do not slide circuit boards over any surface.
Insert circuit boards with the proper orientation.
Use static shielded containers for storing and trasporting circuit boards
Electrostatic Discharge (ESD) Precautions

EN-8
The PA720 is a high-performance power amplier that delivers 7 channels of ecient Class G amplication. With an impressive 140W per channel, the PA720 is designed to oer the greatest exibility and power without compromising
on control.
Featuring the best-in-class components including a toroidal based power supply, acoustically damped chassis, paralleled transistor output stages and exceptionally low levels of distortion, the PA720 masters the reproduction of music
with all its originality and detail for an unmatched level of sound quality and clarity.
HIGHLIGHTS
• Balanced XLR and Single ended RCA analogue inputs
• RS232 and IP control
• 140WPC class G amplication
• Total harmonic distortion + noise = 0.002%
ROUTINE MAINTENANCE
There is routine maintenance that should performed on a periodic basis to prevent the unit from degrading in performance and cosmetic condition. Clean the exterior with a soft, lint-free cloth. Do not use alcohol, benzene, acetone-
based cleaners, or strong commercial cleaners. If the unit is exposed to a dusty environment, you can use a vacuum with a brush attachment to suck all dust and debris from the unit. Even a low pressure air compressor can be used to
remove dust from its exterior surface. Any cleaning or dusting should be done externally, preventatively.
General Information

EN-9
PA720 Specications
Continuous power output at 0.2% THD per channel
Seven channels driven, 4Ω / 8Ω, 1kHz 140W / 100W
Five channels driven, 4Ω / 8Ω, 1kHz 175W / 110W
Two channels driven, 4Ω / 8Ω, 1kHz 225W / 140W
Harmonic distortion, 80% power, 8Ω at 1kHz 0.002%
Inputs
RCA Type XLR Type
Input sensitivity 100W / 8Ω 800mV RMS 1.6V RMS
Signal/Noise ratio (A-wtd) 100W / 8Ω 112dB
Input impedance 10kΩ
Frequency response 20 - 20kHz +/-0.05dB
General
Mains voltage 110–120V or 220–240V, 50–60Hz
Maximum power consumption 1.5kW
Low power standby consumption 0.5W
Network standby consumption 2W
Dimensions W x H x D (including feet,
control knob and speaker terminals)
433 x 425 x 177mm
Weight (net) 18kg
Weight (gross) 19.7kg
All specication values are typical unless otherwise
stated.Arcamhas a policy of continuousimprovement
for its products. This means that designs and
specications are subject to change without notice.
E&OE.

EN-10
Functional Verication and Test Procedure
1. Check mains power consumption at idle (no inputs or loads connected).
Expect to see 60 – 70W @ 230V.
2. Set bias to 20mV +/-1mV when hot.
3. Check DC osets at speaker terminals with DVM (no inputs or loads connected)
Should be < 10mV, typically 5mV.
4. Check residual noise oor (no inputs connected)
8R load – balanced feed to analyser input.
10-500kHz input lter, amplitude should be < 450uV, typically 400uV
10-22kHz input lter, amplitude should be < 300uV, typically 250uV
10-22kHz A weighted input lter, amplitude should be < 90uV, typically 70uV
5. Check THD (RCA input)
8R load – balanced feed to analyser input.
Select RCA input with rear panel switch.
Generator output to 1kHz, level to get approx. 10V output, typically 320mV into one channel.
10-22kHz input lter, THD should be < 0.001%, typically 0.0008%.
6. Check THD (XLR input)
8R load – balanced feed to analyser input.
Switch to XLR input with rear panel switch.
Generator output to 1kHz, level to get approx. 10V output, typically 640mV into one channel.
10-22kHz input lter, THD should be < 0.001%, typically 0.0008%.
7. Check THD into 4R (XLR input)
4R load – balanced feed to analyser input.
Generator output to 1kHz, level to get approx. 10V output, typically 640mV into one channel.
10-22kHz input lter, THD should be < 0.0012%, typically 0.0009%
8. Check maximum output level into 8R
8R load – balanced feed to analyser input.
Generator output level to get approx. 30V output level, this is with all channels driven.
THD should be < 0.01%, typically 0.002%.
9. Check maximum output level into 4R
4R load – balanced feed to analyser input.
Generator output level to get approx. 30V output level, this is with all channels driven.
THD should be < 0.01%, typically 0.002%.
10. Check maximum output level (XLR jack)
Switch to XLR input with rear panel switch.
8R load – balanced feed to analyser input.
Double input signal level WRT step 9
THD should be < 0.01%, typically 0.002%.
11. Check short circuit protection
Set input level to get approx. 3V on the speaker output.
Short one of the outputs.
Unit should shut down.
12. Check RS232
Connect RS232 to unit.
Open PA720 console.
In Connection tab select com port and set baud rate to 38400.
In RS232 command tab request mute status (make sure RS232 tick box is checked).
Check there is a response.
13. Check Ethernet
Connect Ethernet cable to unit.
In RS232 command tab request IP address (make sure RS232 tick box is checked) and make a note of IP
address.
Enter IP address in connection tab.
In RS232 command tab request mute status (make sure TCPIP tick box is checked not RS232).
Check there is a response.
14 Check Trigger out
Connect DVM to trigger output. Should read 12V.
Put unit into standby.

EN-11
Check trigger output drops to 0V.
Turn unit back on.
15. Check USB update
Load the image.hex le into the root of a USB stick.
Turn the unit o (hard power not standby)
Insert USB stick
Turn the unit on
The unit should update (look for the standby LED ashing)
16. Restore defaults
In RS232 command tab select factory reset and send command.

EN-12EN-12
Troubleshooting
Problem Check the following
No sound The PA720 / PA240 / PA410 power amplier is correctly plugged in and
switched on.
Your audio/video source (e.g. pre amplier) is correctly connected.
The PA720 / PA240 / PA410 is not in protection mode, as described in
the next section.
The PA720, PA240 and PA410 is not muted.
Check RCA/XLR input switch is in the correct position.
Sound cuts-out unexpectedly The PA720 / PA240 / PA410 may enter a protection mode, depending on
the fault being detected. The front panel LED will indicate the fault type,
according to the list below.
FLASHING WHITE: The internal temperature of the unit reached an
unsafe level. Allow the PA720 / PA240 / PA410 to cool o.
FLASHING RED: The PA720 / PA240 / PA410 amplier detected a
speaker short circuit. Should this happen, please inspect all the
speaker cables to make sure none of them are shorted together. This
fault is very common when bare wires are being used to make speaker
connections.
FLASHING ORANGE: PA720 and PA240 only. The amplier detected a
DC oset.
Following any of the faults described above, the amplier will turn itself
o and power to the speakers will be removed. To continue using the
PA720 / PA240 / PA410, the fault must be removed and the unit must be
turned OFF then back ON.

EN-13
Theory of Operation
The PA720 contains ve PCBs, the power amplier PCB,
pre-amplier PCB, lifter PCB, mains input PCB and front
panel PCB. What follows is an overview of each PCB as
well as any signals that go between the PCBs.
A note on standby modes
The PA720 has a number of dierent standby modes.
Modes are selected by simply sending a command over
the relevent control interface. To go back to the default
low power standby mode while the unit is powered up
press and hold the standby button on the front panel
for more than 3 seconds.
Standby Mode Note
RS232 NET
OFF OFF Lowest power mode.
Network module disabled
no RS32 or IP control.
ON OFF Network module disabled.
RS232 control availble, no
IP control
ON ON Network module enabled.
RS232 and IP control
availble.
Power Amplier PCB - L281
The power amplier PCB consisits of 7 identical
channels.
All channels share a common main power rail of +/-
55VDC. The main output is powered with a switched
voltage +/-VLIFT, that will change between +/-30VDC
and +/-55VDC depending on the required output signal
level. All of which are supplied by the lifter PCB.
Irrespective of input type (RCA or XLR) the amplier is
fed via a balanced signal.
Pre-amplier PCB - L282
The preamp PCB has four main sections
• Host microcontroller (MCU).
• Network interface.
• Balanced (XLR) audio inputs.
• Single ended (RCA) audio inputs.
Host MCU
The host MCU IC400 controls all the functions of the
PA720 such as input type selection, muting, controling
the power supply, RS232 communications, interfacing
to the network module and monitoriong the amplier
status.
The MCU is powered by 3.3V generated locally from the
5V rail by REG500.
Network Interface
The network interface consists of an ethernet phy,
IC300, which is the interface to to the outside world. This
is controlled by the host MCU
XLR Audio Inputs
The XLR inputs are simply level shifted by a potential
divider, buered then sent via a relay to select between
XLR or RCA inputs to the power amplier via CON2.
NOTE: The XLR and RCA inputs are mutually
exclusive i.e only one type of input can be enabled
at any one time. You cannot mix input types.
RCA Audio Inputs
As the power amplier PCB requires a balanced input
the singled ended input is level shifted then then
converted to balanced.
Mains Input PCB - L283
The mains input PCB contains the main power relays
which control the power transfomer. The power
transformer has a soft start circuit where it is intially
connected to the main via a high current NTC to limit
the initial inrush current. This NTC is then bypassed once
the main PSU has stabilised.
The 5V and 3.3V standby rails are also generated here.
Lifter PCB - L284
The PA720 is a class G amplier and as such requires
two power rails for the output devices. The lifter PCB
contains the rectiers for both rails and also the circuitry
to switch between these rails depending on the output
level required by the amplier

EN-14EN-14
L281 Power Amplier PCB Issue 3

EN-15
23425
Bill of Materials
Part Description AMP019 Amplifier PCB Assembly
Part Number L281AY
Issue 3.0.0
Report Type Fitted Parts Only
AMP019 Amplifier PCB Assembly
Part Number Quantity Description Issue Designators
Resistor 1206 Surface Mount 0.25W 1% 68R R1005 R1046 R1069 R1117 R2005 R2046 R2069 R2117
R3005 R3046 R3069 R3117 R4005 R4046 R4069 R4117
R5005 R5046 R5069 R5117 R6005 R6046 R6069 R6117
R7005 R7046 R7069 R7117
1A068 28 1
Resistor 1206 Surface Mount 0.25W 1% 180R R1 R11 R16 R23 R61A118 5 1
Resistor 1206 Surface Mount 0.25W 1% 2K7 R1067 R1080 R2067 R2080 R3067 R3080 R4067 R4080
R5067 R5080 R6067 R6080 R7067 R7080
1A227 14 1
Resistor 1206 Surface Mount 0.25W 1% 3K3 R22 R241A233 2 1
Resistor 1206 Surface Mount 0.25W 1% 6K8 R80001A268 1 1
Resistor 1206 Surface Mount 0.25W 1% 12K R1034 R1036 R1088 R1090 R2034 R2036 R2088 R2090
R3034 R3036 R3088 R3090 R4034 R4036 R4088 R4090
R5034 R5036 R5088 R5090 R6034 R6036 R6088 R6090
R7034 R7036 R7088 R7090
1A312 28 1
R SM1210 1% 1R0 0.5W R1035 R1086 R2035 R2086 R3035 R3086 R4035 R4086
R5035 R5086 R6035 R6086 R7035 R7086
1AA810 14 A
Resistor 2512 Surface Mount 1W 1% 47R R1006 R1102 R2006 R2102 R3006 R3102 R4006 R4102
R5006 R5102 R6006 R6102 R7006 R7102
1AB047 14 1
Resistor 2512 Surface Mount 1W 1% 1K5 R1037 R1091 R2037 R2091 R3037 R3091 R4037 R4091
R5037 R5091 R6037 R6091 R7037 R7091
1AB215 14 1
Resistor 1206 Surface Mount 0.5W 1% 0R47 R2023 R2024 R3023 R3024 R4023 R4024 R7023 R70241AC947 8 1
Resistor Carbon Film 2W 5% 100R R18 R26 R29 R30 R311C110 5 0
Resistor Carbon Film 2W 5% 3R3 R1075 R2075 R3075 R4075 R5075 R6075 R70751C833 7 0
Resistor Carbon Film 2W 5% 4R7 R12 R13 R17 R2 R5 R7 R91C847 7 1
Resistor 0805 Surface Mount 0.1W 0.1% 1K R1059 R1089 R2059 R2089 R3059 R3089 R4059 R4089
R5059 R5089 R6059 R6089 R7059 R7089
1L210 14 1
Resistor 0805 Surface Mount 0.1W 0.1% 2K R1042 R1078 R2042 R2078 R3042 R3078 R4042 R4078
R5042 R5078 R6042 R6078 R7042 R7078
1L220 14 1
Report generated on 15/01/2021 Page 3 of 13

EN-16
23425
Bill of Materials
Part Description AMP019 Amplifier PCB Assembly
Part Number L281AY
Issue 3.0.0
Report Type Fitted Parts Only
AMP019 Amplifier PCB Assembly
Part Number Quantity Description Issue Designators
Resistor 0805 Surface Mount 0.1W 0.1% 3K0 R1056 R1087 R2056 R2087 R3056 R3087 R4056 R4087
R5056 R5087 R6056 R6087 R7056 R7087
1L230 14 1
Resistor 0805 Surface Mount 0.1W 0.1% 30K R1009 R2009 R3009 R4009 R5009 R6009 R70091L330 7 1
Resistor 0805 Surface Mount 0.125W 1% 10R R1030 R2030 R21 R25 R3030 R4030 R5030 R6030
R7030
1M010 9 1
Resistor 0805 Surface Mount 0.125W 1% 22R R1011 R1110 R2011 R2110 R3011 R3110 R4011 R4110
R5011 R5110 R6011 R6110 R7011 R7110
1M022 14 1
Resistor 0805 Surface Mount 0.125W 1% 33R R1028 R1096 R2028 R2096 R3028 R3096 R4028 R4096
R5028 R5096 R6028 R6096 R7028 R7096
1M033 14 1
Resistor 0805 Surface Mount 0.125W 1% 560R R1043 R1073 R2043 R2073 R3043 R3073 R4043 R4073
R5043 R5073 R6043 R6073 R7043 R7073
1M156 14 1
Resistor 0805 Surface Mount 0.125W 1% 2K2 R14 R19 R27 R3 R81M222 5 1
Resistor 0805 Surface Mount 0.125W 1% 3K9 R80111M239 1 1
Resistor 0805 Surface Mount 0.125W 1% 6K8 R1060 R1094 R2060 R2094 R3060 R3094 R4060 R4094
R5060 R5094 R6060 R6094 R7060 R7094
1M268 14 1
Resistor 0805 Surface Mount 0.125W 1% 10K R1040 R1097 R2040 R2097 R3040 R3097 R4040 R4097
R5040 R5097 R6040 R6097 R7040 R7097
1M310 14 1
Resistor 0805 Surface Mount 0.125W 1% 47K R1103 R1118 R2103 R2118 R3103 R3118 R4103 R4118
R5103 R5118 R6103 R6118 R7103 R7118
1M347 14 1
Resistor 0805 Surface Mount 0.125W 1% 120K R80071M412 1 1
Resistor 0805 Surface Mount 0.125W 1% 220K R1041 R1082 R1099 R2041 R2082 R2099 R3041 R3082
R3099 R4041 R4082 R4099 R5041 R5082 R5099 R6041
R6082 R6099 R7041 R7082 R7099
1M422 21 1
Resistor 0805 Surface Mount 0.125W 1% 4R7 R1092 R2092 R3092 R4092 R5092 R6092 R70921M847 7 1
Resistor 0805 Surface Mount Thin Film 0.125W 1% 10K R1010 R2010 R3010 R4010 R5010 R6010 R7010 R80021MA310 8 1
Report generated on 15/01/2021 Page 4 of 13

EN-17
23425
Bill of Materials
Part Description AMP019 Amplifier PCB Assembly
Part Number L281AY
Issue 3.0.0
Report Type Fitted Parts Only
AMP019 Amplifier PCB Assembly
Part Number Quantity Description Issue Designators
Resistor 0805 Surface Mount Thin Film 0.125W 1% 15K R1013 R1014 R2013 R2014 R3013 R3014 R4013 R4014
R5013 R5014 R6013 R6014 R7013 R7014
1MA315 14 1
Resistor 0805 Surface Mount Thin Film 0.125W 1%
100K
R8001 R8004 R8006 R8008 R8009 R8010 R8012 R8013
R8014
1MA410 9 1
Resistor 0603 Surface Mount 0.063W 0R0 R1047 R1058 R2047 R2058 R3047 R3058 R4047 R4058
R5047 R5058 R6047 R6058 R7047 R7058
1N000 14 1
Resistor 0603 Surface Mount 0.063W 1% 10R R1015 R1016 R1049 R1105 R1106 R2015 R2016 R2049
R2105 R2106 R3015 R3016 R3049 R3105 R3106 R4015
R4016 R4049 R4105 R4106 R5015 R5016 R5049 R5105
R5106 R6015 R6016 R6049 R6105 R6106 R7015 R7016
R7049 R7105 R7106
1N010 35 1
Resistor 0603 Surface Mount 0.063W 1% 20R R1095 R2095 R3095 R4095 R5095 R6095 R70951N020 7 0
Resistor 0603 Surface Mount 0.063W 1% 47R R1020 R1027 R1104 R1116 R2020 R2027 R2104 R2116
R3020 R3027 R3104 R3116 R4020 R4027 R4104 R4116
R5020 R5027 R5104 R5116 R6020 R6027 R6104 R6116
R7020 R7027 R7104 R7116
1N047 28 1
Resistor 0603 Surface Mount 0.063W 1% 68R R1032 R1071 R1072 R1083 R1084 R1107 R2032 R2071
R2072 R2083 R2084 R2107 R3032 R3071 R3072 R3083
R3084 R3107 R4032 R4071 R4072 R4083 R4084 R4107
R5032 R5071 R5072 R5083 R5084 R5107 R6032 R6071
R6072 R6083 R6084 R6107 R7032 R7071 R7072 R7083
R7084 R7107
1N068 42 1
Resistor 0603 Surface Mount 0.063W 1% 100R R1031 R1111 R2031 R2111 R3031 R3111 R4031 R4111
R5031 R5111 R6031 R6111 R7031 R7111
1N110 14 1
Resistor 0603 Surface Mount 0.063W 1% 180R -This
part is RoSH compliant.
R1081 R2081 R3081 R4081 R5081 R6081 R70811N118 7 1
Resistor 0603 Surface Mount 0.063W 1% 220R R1029 R1093 R2029 R2093 R3029 R3093 R4029 R4093
R5029 R5093 R6029 R6093 R7029 R7093
1N122 14 1
Resistor 0603 Surface Mount 0.063W 1% 270R R1021 R2021 R3021 R4021 R5021 R6021 R70211N127 7 1
Report generated on 15/01/2021 Page 5 of 13

EN-18
23425
Bill of Materials
Part Description AMP019 Amplifier PCB Assembly
Part Number L281AY
Issue 3.0.0
Report Type Fitted Parts Only
AMP019 Amplifier PCB Assembly
Part Number Quantity Description Issue Designators
Resistor 0603 Surface Mount 0.063W 1% 330R -This
part is RoSH compliant.
R1038 R1052 R1062 R1079 R2038 R2052 R2062 R2079
R3038 R3052 R3062 R3079 R4038 R4052 R4062 R4079
R5038 R5052 R5062 R5079 R6038 R6052 R6062 R6079
R7038 R7052 R7062 R7079
1N133 28 1
Resistor 0603 Surface Mount 0.063W 1% 360R R1108 R1113 R2108 R2113 R3108 R3113 R4108 R4113
R5108 R5113 R6108 R6113 R7108 R7113
1N136 14 1
Resistor 0603 Surface Mount 0.063W 1% 430R R1044 R1076 R2044 R2076 R3044 R3076 R4044 R4076
R5044 R5076 R6044 R6076 R7044 R7076
1N143 14 1
Resistor 0603 Surface Mount 0.063W 1% 1K0 R1002 R1007 R1026 R1033 R1085 R1112 R2002 R2007
R2026 R2033 R2085 R2112 R3002 R3007 R3026 R3033
R3085 R3112 R4002 R4007 R4026 R4033 R4085 R4112
R5002 R5007 R5026 R5033 R5085 R5112 R6002 R6007
R6026 R6033 R6085 R6112 R7002 R7007 R7026 R7033
R7085 R7112
1N210 42 1
Resistor 0603 Surface Mount 0.063W 1% 1K5 R1017 R1025 R1074 R1098 R1109 R1114 R2017 R2025
R2074 R2098 R2109 R2114 R3017 R3025 R3074 R3098
R3109 R3114 R4017 R4025 R4074 R4098 R4109 R4114
R5017 R5025 R5074 R5098 R5109 R5114 R6017 R6025
R6074 R6098 R6109 R6114 R7017 R7025 R7074 R7098
R7109 R7114
1N215 42 1
Resistor 0603 Surface Mount 0.063W 1% 2K7 R1045 R1077 R2045 R2077 R3045 R3077 R4045 R4077
R5045 R5077 R6045 R6077 R7045 R7077
1N227 14 1
Resistor 0603 Surface Mount 0.063W 1% 3K3 R1019 R1022 R1101 R2019 R2022 R2101 R3019 R3022
R3101 R4019 R4022 R4101 R5019 R5022 R5101 R6019
R6022 R6101 R7019 R7022 R7101
1N233 21 1
Resistor 0603 Surface Mount 0.063W 1% 4K7 R1000 R1039 R1100 R2000 R2039 R2100 R3000 R3039
R3100 R4000 R4039 R4100 R5000 R5039 R5100 R6000
R6039 R6100 R7000 R7039 R7100 R8003 R8005
1N247 23 1
Resistor 0603 Surface Mount 0.063W 1% 5K1 R1008 R2008 R3008 R4008 R5008 R6008 R70081N251 7 1
Report generated on 15/01/2021 Page 6 of 13

EN-19
23425
Bill of Materials
Part Description AMP019 Amplifier PCB Assembly
Part Number L281AY
Issue 3.0.0
Report Type Fitted Parts Only
AMP019 Amplifier PCB Assembly
Part Number Quantity Description Issue Designators
Resistor 0603 Surface Mount 0.063W 1% 5K6 -This
part is RoSH compliant.
R6018 R61151N256 2 1
Resistor 0603 Surface Mount 0.063W 1% 6K8 R1018 R1115 R2018 R2115 R3018 R3115 R4018 R4115
R7018 R7115
1N268 10 1
Resistor 0603 Surface Mount 0.063W 1% 8K2 R5018 R51151N282 2 1
Resistor 0603 Surface Mount 0.063W 1% 10K R1001 R1004 R2001 R2004 R3001 R3004 R4001 R4004
R5001 R5004 R6001 R6004 R7001 R7004
1N310 14 1
Resistor 0603 Surface Mount 0.063W 1% 100K R10 R15 R20 R28 R41N410 5 1
Resistor 0603 Surface Mount 0.063W 1% 3M3 R1003 R2003 R3003 R4003 R5003 R6003 R70031N533 7 1
Resistor 0603 Surface Mount 0.063W 1% 10M0 R9006 R9007 R9008 R9009 R9015 R9017 R9018 R9019
R9025 R9027 R9028 R9029 R9033 R9034
1N610 14 1
Resistor 0603 Surface Mount 0.063W 1% 4R7 R1051 R1061 R2051 R2061 R3051 R3061 R4051 R4061
R5051 R5061 R6051 R6061 R7051 R7061
1N847 14 1
Thermistor NTC 100R 0603 Package TH1001 TH2001 TH3001 TH4001 TH5001 TH6001 TH70011T013 7 A
Thermistor NTC 47K 0603 Package TH1000 TH1002 TH2000 TH2002 TH3000 TH3002 TH4000
TH4002 TH5000 TH5002 TH6000 TH6002 TH7000 TH7002
1T021 14 1
Resistor Thick Film RL73 2W 0.18R R1053 R1054 R1063 R1064 R2053 R2054 R2063 R2064
R3053 R3054 R3063 R3064 R4053 R4054 R4063 R4064
R5053 R5054 R5063 R5064 R6053 R6054 R6063 R6064
R7053 R7054 R7063 R7064
1W918 28 1
Link Plain 8MM Bandoliered J1000 J1001 J1002 J1003 J1004 J1005 J1006 J1007
J2000 J2001 J2002 J2003 J2004 J2005 J2006 J2007
J3000 J3001 J3002 J3003 J3004 J3005 J3006 J3007
J4000 J4001 J4002 J4003 J4004 J4005 J4006 J4007
J5000 J5001 J5002 J5003 J5004 J5005 J5006 J5007
J6004 J6005 J6006 J6007 J7000 J7001 J7002 J7003
J7004 J7005 J7006 J7007
1X008A 52 1
Report generated on 15/01/2021 Page 7 of 13

EN-20
23425
Bill of Materials
Part Description AMP019 Amplifier PCB Assembly
Part Number L281AY
Issue 3.0.0
Report Type Fitted Parts Only
AMP019 Amplifier PCB Assembly
Part Number Quantity Description Issue Designators
Capacitor SM 0805 X7R Ceramic 10% 50V 22N C1010 C1029 C2010 C2029 C3010 C3029 C4010 C4029
C5010 C5029 C6010 C6029 C7010 C7029
2J322 14 1
Capacitor SM 0805 X7R Ceramic 10% 100V 220N C1004 C1036 C2004 C2036 C3004 C3036 C4004 C4036
C5004 C5036 C6004 C6036 C7004 C7036
2JA422 14 1
Capacitor SM 1206 X7R Ceramic 10% 100V 100N -This
part is RoHS compliant.
C80012JB410 1 1
Capacitor SM 1206 X7R Ceramic 10% 25V 1UFC1000 C2000 C3000 C4000 C5000 C6000 C70002JB510 7 1
Capacitor SM 1206 X7R Ceramic 10% 100V 1UFC1006 C1041 C2005 C2006 C2032 C2041 C3005 C3006
C3032 C3041 C4005 C4006 C4032 C4041 C5006 C5041
C6006 C6041 C7005 C7006 C7032 C7041
2JB510B 22 1
Capacitor SM 0603 X7R Ceramic 10% 50V 1N0 C1040 C2040 C3040 C4040 C5040 C6040 C70402JC210 7 1
Capacitor SM 0603 X7R Ceramic 10% 50V 100N C1007 C1012 C1015 C1031 C1037 C1038 C1043 C1044
C1046 C1047 C2007 C2012 C2015 C2031 C2037 C2038
C2043 C2044 C2046 C2047 C3007 C3012 C3015 C3031
C3037 C3038 C3043 C3046 C4007 C4012 C4015 C4031
C4037 C4038 C4044 C4047 C5007 C5012 C5015 C5031
C5037 C5038 C5043 C5044 C5046 C5047 C6007 C6012
C6015 C6031 C6037 C6038 C6043 C6044 C6046 C6047
C7007 C7012 C7015 C7031 C7037 C7038 C7043 C7046
C8000 C9000 C9001 C9002 C9003 C9004 C9005 C9006
C9007 C9008 C9009 C9010 C9011 C9012 C9013 C9014
C9015 C9016 C9017
2JC410 83 1
Capacitor Boxed Polyester 5mm Pitch 5% 100VDC 100N C1020 C2020 C3020 C4020 C5020 C6020 C70202KA410 7 1
Capacitor Boxed Polyester 5mm Pitch 5% 100VDC 470N C1001 C2001 C3001 C4001 C5001 C6001 C70012KA447 7 1
Capacitor SM 0805 NPO Ceramic 5% 100V 22P C1003 C1022 C1025 C2003 C2022 C2025 C3003 C3022
C3025 C4003 C4022 C4025 C5003 C5022 C5025 C6003
C6022 C6025 C7003 C7022 C7025
2L022 21 1
Capacitor SM 0805 NPO Ceramic 5% 100V 33P C1017 C1027 C2017 C2027 C3017 C3027 C4017 C4027
C5017 C5027 C6017 C6027 C7017 C7027
2L033 14 1
Report generated on 15/01/2021 Page 8 of 13