K & K Audio Extreme RAKK Mark III User manual

RAKK dac
Ralei
g
h Audio
K&K Audio
RAKK dac
Mark III
Extreme RAKK dac
Assembly Manual
Version 1.1 © 2010 Raleigh Audio

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This completed Extreme RAKK dac has a silver face plate and knobs. A black faceplate and knobs is available.
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1

GeneralInformation
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The Extreme RAKK dac is a semi-custom kit, which means that several standard offerings can
be combined in different ways. You can choose to have an optional volume control and optional
select switch. You can choose to have one to four inputs which may be a mix of SPDIF,
AES/EBU, USB or I2S. These are covered in this manual although all of the possible
combinations are not shown. However, those things not shown can be easily inferred from other
things that are shown. Some interfaces, such as TOSLINK, are not included in this manual but
are available as special-order items.
This kit is relatively straightforward to build, but assumes some prior skill with a soldering iron
and some knowledge of electronic components and assembly.
Kit version
Use this manual with the Extreme RAKK dac Mark III
•Use the applicable on-line manuals for component sub-assemblies.
Required Tools and Supplies
150 to 250 Watt soldering gun
35 to 50 Watt soldering iron
Phillips (cross point) screwdriver
Volt-Ohm-Milliamp Meter
Potentiometer adjustment tool (supplied)
1/16” hex (Allen) wrench (supplied)
5/64” hex (Allen) wrench (supplied)
1.5mm. hex (Allen) wrench (supplied)
2.5mm. hex (Allen) wrench (supplied)
1/4”, 5/16”, 1/2”, 9/16” open-end wrenches
Diagonal cutting pliers
Long-nose pliers
Wire stripper
Solder
Use the soldering gun only to solder the heatsink pins.
Use the soldering iron for all other components.
Support
RAKK dac and its associated components are produced through the joint cooperation of K&K
Audio and Raleigh Audio. You may contact us with questions on constructing this kit by sending
an e-mail message to [email protected] or [email protected]
2

Warnings and Cautions
Warning — a high voltage power supply (200VDC) is required to make the kit operate properly.
These voltages can be lethal. If you are not familiar with safe techniques for completing the
installation of this kit with a high voltage power supply, then you should seek someone who is
qualified to help you construct this kit safely. If you wish to review safe practice, consult the
ARRL Handbook for Radio Amateurs (www.arrl.org or often at used book stores), which has a
section on high voltage safety. Although they are usually referring to 1000v+, the techniques are
still applicable. As the purchaser, you assume responsibility for safe assembly, testing, and
application of this kit.
Caution – Use only solder that is intended for electrical circuits. Do not use acid or corrosive
flux of any kind.
Caution – Any MOSFET is subject to damage by static electricity. Thus, the MOSFETs need
special care and handling especially when the relative humidity is low. Make sure to discharge
any static electrical charge from your body before handling a MOSFET. You can discharge your
body by touching a water faucet or grounded electrical appliance.
Soldering Notes
To a large extent, the success of your kit-building endeavor depends on your ability to solder
properly. Aside from experience, there are two pretty important factors in this success. The first
is the soldering equipment. I recommend using a temperature controlled soldering station,
although any good soldering iron of 40 watts or greater will do. There are many soldering
stations on the market; I have had good experience with the moderately priced Hakko Model
936. If you do have or purchase a soldering station, or even use your existing soldering iron, I
have found a chisel style tip of about 2mm-2.5mm width to be the most useful. You can use the
flat part for large solder joints and the corner for small solder joints. The second factor is the
selection of the solder you will use. The PC boards and most of the electrical components in the
kit are lead-free, as the movement in the EU has forced manufacturers to remove the lead (and
other dangerous heavy metals) from their products. Decent (notice, I didn’t write “good”) lead-
free solder exists, such as Cardas Tri-Eutectic, but it is not so easy to use unless you have some
soldering experience. Lead-free solder tends to melt in a sluggish way and the resulting solder
joints are not the customary shiny silver color, so it’s difficult to avoid “cold” solder joints
without experience. It’s up to you to decide what to use. Choose based on your experience. I
use Cardas Quad Eutectic and can recommend it without reservation; however other high quality
solders may work just as well. Take care in handling electronic solder as most of it still contains
a significant quantity of lead. Wash your hands thoroughly after construction sessions and keep
all kit materials well out of the reach of small children.
Even though there is a “component side” and solder side” to the board, your might find it more
convenient to solder the leaded components from the component side.
3

TableofContents
General Information ......................................................................................................................................................2
Table of Contents...........................................................................................................................................................4
Assembly Instructions ...................................................................................................................................................5
Pre-wire the printed circuit boards ................................................................................................................................6
Pre-wire the Power Output Module (for RAKK dac) ................................................................................................7
Pre-wire the Power Output Module (for I2S or USB Adapter) .................................................................................7
Pre-wire the Power Boost Module.............................................................................................................................7
Pre-wire the Active Output........................................................................................................................................8
Pre-wire the RAKK dac...........................................................................................................................................10
Pre-wire the USB to I2S Adapter (if used)..............................................................................................................11
Pre-wire the I2S Interface Adapter (if used)............................................................................................................12
Pre-assemble the USB Adapter or I2S Adapter with the RAKK dac ......................................................................13
Pre-wire the Power Transformer .................................................................................................................................14
Panel Preparation.........................................................................................................................................................16
Bottom Panel Preparation ........................................................................................................................................16
Top Panel Preparation .............................................................................................................................................17
Back Panel Preparation............................................................................................................................................17
Side Panel Preparation.............................................................................................................................................18
Front Panel Preparation ...........................................................................................................................................18
Panel Assembly ...........................................................................................................................................................19
Bottom Panel Assembly ..........................................................................................................................................19
Back Panel Assembly ..............................................................................................................................................27
Front Panel Assembly..............................................................................................................................................33
Final Assembly and Wiring.........................................................................................................................................34
Wire the Bottom Panel to the Back Panel................................................................................................................34
Wire the Bottom Panel to the Front Panel ...............................................................................................................38
Assemble the Panels ................................................................................................................................................44
Install Internal Cables..............................................................................................................................................44
Final Adjustments........................................................................................................................................................49
Adjust the Constant Current Sources.......................................................................................................................49
Adjust the Front Panel LEDs...................................................................................................................................50
Final Assembly............................................................................................................................................................50
Parts List......................................................................................................................................................................51
Circuit kits ...............................................................................................................................................................51
Front Panel Options .................................................................................................................................................51
Input Options ...........................................................................................................................................................52
Extreme Kit Contents ..............................................................................................................................................53
Document version history............................................................................................................................................56
4

AssemblyInstructions
Before you start, read through the instructions completely to the end.
Inventory the kit contents to become familiar with the parts and to make sure you have
everything.
The assembly sequence is as follows:
1. Assemble all of the printed circuit boards
2. Pre-wire the printed circuit boards
3. Pre-wire the power transformer
4. Install PC boards and the power transformer on the bottom panel
5. Assemble the components on the back panel
6. Assemble the components on the front panel
7. Assemble the panels
8. Wire everything together
There are two sizes of stranded wire provided with the kit, #22 and #20. The larger diameter #20
is used for power and high voltage. The smaller diameter #22 is used for signal and low voltage.
Where a wire is to be connected to a PC board, prepare the end by stripping ⅛” insulation and tin
the bare wire. For other connections, strip ¼” and tin the end. Where a twisted-pair is called for,
provide about four or five twists per inch. Twisting wires together will shrink their length
slightly so you need to take this into account. With a very few exceptions, which are explicit,
insert the wire into the pad from the bottom, or solder side, of the board. Wires should be
dressed neatly as close to the bottom of the enclosure as possible.
Assemble the Printed Circuit Boards
Depending upon the feature mix that you have chosen, the boards that you will assemble will
vary. In all cases your project will include a RAKK dac, an Active Differential Output board, a
Low-Voltage Power System Output Module and Power Boost Module. You may also have
chosen to have a USB adapter, or an I2S adapter and their associated power Output Modules.
While assembly of all of the boards is straight-forward, the Active Differential Output is the
most complex. Therefore, I recommend that you leave that board until you have assembled all of
the other boards.
The assembly manuals for the boards include installation instructions that you will not use.
Rather than using those general instructions, you will follow the specific installation
instructions contained in this manual.
Referring to the applicable on-line manuals, assemble the boards now.
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5

Prewiretheprintedcircuitboards
In the following steps, the wires should be inserted into the solder side of the board. “Preparing a
wire” means to strip ⅛” of insulation from both ends of the wire and tin the ends.
Because each wire has a “from” end and “to” end, and only one end is pre-wired, some pads are
not wired in this section. A signal line or a function will likely have the same name on the
“from” end as it does on the “to” end, therefore don’t just go by the name when you install the
wire. Rather, check that you are installing it on the proper board.
Basically there are two ways to make a twisted pair or a multi-wire cable. The quick and easy
way is to use an electric drill. So if you have a variable speed drill, all you have to do is to put
the wires together in the drill chuck and turn on the drill. It might take a little practice to get the
tension and speed right but once you get the knack, it is quick and easy to do. If you don’t have a
drill handy, the old-fashioned way of manually twisting the wires works fine. I have described
how I do it here. To make a multi-wire cable, first make a twisted pair and then wrap a third
wire around the twisted pair following the lay of one of the wires. Then stretch this new wire like
you did the others. Follow with a fourth and fifth wire as needed.
About 5% shrinkage occurs when making a twisted pair. So for example, if you wanted a 10”
long twisted pair, you would make it from two 10½” wires. It would be better to err a little on the
long side because you can always trim the length when you install the twisted pair.
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6

PrewirethePowerOutputModule(forRAKKdac)
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If you have two Power Output modules, this is the one that will be used to power the RAKK dac.
Prepare a 3” #22 red/black twisted pair.
•Connect the red wire to the 12VDC Output “+” pad.
•Connect the black wire to the 12VDC Output “-” pad.
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PrewirethePowerOutputModule(forI2SorUSBAdapter)
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Skip this section if you do not have a USB or I2S Adapter.
Prepare a 17” #22 red/black twisted pair.
•Connect the red wire to the 12VDC Output “+” pad.
•Connect the black wire to the 12VDC Output “-” pad.
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PrewirethePowerBoostModule
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1. Prepare a 13” #22 red/black twisted pair.
•Connect the red wire to the 12VDC Output “+” pad.
•Connect the black wire to the 12VDC Output “-” pad.
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2. Prepare a 5¼” #22 red/black twisted pair.
•Connect the red wire to the LED “A” pad.
•Connect the black wire to the LED “C” pad.
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7

PrewiretheActiveOutput
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Wire the Input Select on the Active Output
1. Connect a jumper wire between the two Input Select pads.
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Wire the Volume Control on the Active Output
(skip this section if you do not have a volume control)
2. Prepare a 5½” #22 blue/black twisted pair.
•Connect the blue wire to the volume control “L+” pad.
•Connect the black wire to the volume control “L-” pad.
3. Prepare a 4½” #22 orange/black twisted pair.
•Connect the orange wire to the volume control “R+” pad.
•Connect the black wire to the volume control “R-” pad.
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8

Wire the “From RAKK dac” inputs on the Active Output
4. Prepare a 4” #22 black wire.
•Connect it to the “REF” pad.
5. Prepare a 4” #22 orange/black twisted pair.
•Connect the orange wire to the “R+” pad.
•Connect the black wire to the “R-” pad.
6. Prepare a 4” #22 blue/black twisted pair.
•Connect the blue wire to the “L+” pad.
•Connect the black wire to the “L-” pad.
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The Line Input pads are not used.
The external mute pads are not used. 
9

PrewiretheRAKKdac
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Wire the Input Select on the RAKK dac
The RAKK dac offers four inputs: three SPDIF or AES/EBU inputs and one I2S input. Inputs 1
through 3 are the SPDIF or AES/EBU inputs and Input 4 is always the I2S input, even if you are
using only a single input.
1. If you have chosen to use only a single input, install a jumper wire between the Input Select
pad for that input and the adjacent “com” pad.
2. If you have chosen to use multiple inputs, you will prepare a 12½” cable. Either twist the
needed wires together with a drill or make the cable manually as follows:
•Prepare a 12½” #22 blue/black twisted pair.
•Prepare a 13½” #22 orange wire. Twist this wire around the blue/black twisted pair.
•If you are using a third input, prepare a 13¾” #22 violet wire. Twist this wire around the
other wires.
•If you are using a forth input, prepare a 14” #22 red wire. Twist this wire around the other
wires.
3. Connect the cable that you have prepared:
•Connect the black wire to the Input Select “com” pad.
•Connect the blue wire to the Input Select pad selected by switch position 1.
•Connect the orange wire to the Input Select pad selected by switch position 2.
•Connect the violet wire to the Input Select pad selected by switch position 3.
•Connect the red wire to the Input Select pad selected by switch position 4.
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Wire the SPDIF Lock LED
(skip this step if you are using only input 4.)
4. Prepare a 13” #22 red/black twisted pair.
•Connect the red wire to the Lock LED “A” pad.
•Connect the black wire to the Lock LED “C” pad.
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Inputs 1 through 3 will be pre-wired on the back panel assembly. Input 4 will be wired as part of
the attachment of its board to the RAKK dac.
We have found the “Mute” function to be of little value so that LED is not used.
10

PrewiretheUSBtoI2SAdapter(ifused)
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Wire the I2S Output
1. Mount four 1” standoffs on the bottom of the USB Adapter and secure with 6-32 screws.
2. Insert a ½” 6-32 setscrew about half-way into each 1” standoff.
3. Install a ⅜” standoff as a nut on each of the four 1” standoffs.
4. Cut three pieces of #22 black wire, each 1.375” long. 1.375” is the length of the two
standoffs, which may be used as a gauge.
5. Cut three pieces of #22 violet wire, each 1.375” long.
6. Strip ¼” of insulation from each end of the wires and tin the ends by melting a little solder
onto the stripped ends.
7. Insert the three black wires from the bottom of the board into the following three locations:
•DATA -
•LRCK -
•BCK -
8. Solder and trim the leads.
9. Insert the three violet wires from the bottom of the board into the following three locations:
•DATA +
•LRCK +
•BCK +
10. Solder and trim the leads.
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11

PrewiretheI2SInterfaceAdapter(ifused)
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Wire the I2S Output
1. Mount four 1” standoffs on the bottom of the I2S Adapter and secure with 6-32 screws.
2. Insert a ½” 6-32 setscrew about half-way into each 1” standoff.
3. Install a ⅜” standoff as a nut on each of the four 1” standoffs.
4. Cut three pieces of #22 black wire, each 1.375” long. 1.375” is the length of the two
standoffs, which may be used as a gauge.
5. Cut three pieces of #22 violet wire, each 1.375” long.
6. Strip ¼” of insulation from each end of the wires and tin the ends by melting a little solder
onto the stripped ends.
7. Insert the three black wires from the bottom of the board into the following three locations:
•DATA -
•LRCK -
•BCK -
8. Solder and trim the leads.
9. Insert the three violet wires from the bottom of the board into the following three locations:
•DATA +
•LRCK +
•BCK +
10. Solder and trim the leads.
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Note that the 12V Power Isolation circuitry on the board is not used. The associated “Input” and
“Output” pads should be left vacant.
We have found the “attached” LED function to be of little value so it is not used.
12

PreassembletheUSBAdapterorI2SAdapterwiththeRAKKdac
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Steps preceded by a “note” (♪) deal with components which must be oriented properly.
Skip this section if you do not have either a USB Adapter or an I2S Adapter.
1. Remove the 3/8” standoffs from the 1” standoffs on the adapter.
♪
2. Set the adapter on top of the RAKK dac such that the I2S Output pads on the USB (I2S)
Adapter align with the Input 4 – I2S pads on the RAKK dac.
3. Insert the six I2S interface wires into the proper pads on the RAKK dac.
4. Install the four 3/8” standoffs as nuts to hold the two pieces together.
5. Solder the six interface wires.
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13

PrewirethePowerTransformer
For the following steps, refer to the LL1683 Data sheet.
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1. Wire the transformer for your Mains line voltage:
115VAC:
•Connect pin 2 to pin 12 with a #20 black wire.
•Connect pin 4 to pin 10 with a #20 black wire.
230VAC:
•Connect pin 4 to pin 12 with a #20 black wire.
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2. Fabricate a T-shaped AC power cable as follows:
•Cut a #20 black wire, 9½ inches long. Do not strip the ends.
•Cut a #20 black wire, 19¾ inches long. Do not strip the ends.
•Cut a #20 white wire, 17½” long. Do not strip the ends.
•Align the white wire with the longer black wire and twist them together for about 10”.
•Align the other black wire with the other end of the white wire and twist them together
for 4½”.
•Go back to the first pair (that you twisted to 10”) and continue the twist until you get to
the junction of the second pair.
•Now twist the two black wires together until you get to the end. Don’t worry if the two
black wires are different length – you will trim them later.
————————————————————————————
3. Wire the AC cable that you just fabricated:
•Trim the 4½” stub to be 4¼” long.
•Separate the end of the stub for 2¼”.
•Trim 1¾” from the end of the black wire.
•Strip ¼” from the end of both wires and tin the ends.
•Connect the white wire to pin 10.
•Connect the black wire to pin 2.
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14

4. Wire the high voltage:
•Make a twisted-pair from two pieces of #20 red wire, one 10” long and one 10¼” long.
Align the wires evenly at one end.
•Connect the longer wire at the uneven end to pin 17 on the power transformer.
•Connect the shorter wire to pin 15 on the power transformer.
————————————————————————————
5. Connect the center tap in the following manner:
•Prepare a 12½” piece of #20 black wire and strip 1” from one end. Connect the tip of this
end to pin 24 and then wrap the bare wire around pin 22. Solder both pins.
•Dress this wire towards pin 15 and wrap it around the red twisted pair following the lay
of the twist.
•Trim the black wire to be the same length as the two red wires.
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6. Wire the filament power
•Make a twisted-pair from two pieces of #20 grey wire, one 5” long and one 7¼” long.
Align the wires evenly at one end.
•Connect the longer wire at the uneven end to pin B1 on the power transformer.
•Connect the shorter wire to pin B6 on the power transformer.
————————————————————————————
7. Wire the RAKK dac AC power
•Make a twisted-pair from two pieces of #20 grey wire, one 7” long and one 9¾” long.
Align the wires evenly at one end.
•Connect the longer wire at the uneven end to pin B7 on the power transformer.
•Connect the shorter wire to pin B4 on the power transformer.
————————————————————————————
Skip this step if you do not have a USB Adapter or an I2S Adapter.
8. Wire the I2S Adapter or USB Adapter AC power
•Make a twisted-pair from two pieces of #20 grey wire, one 4¾” long and one 6⅛” long.
Align the wires evenly at one end.
•Connect the longer wire at the uneven end to pin B8 on the power transformer.
•Connect the shorter wire to pin B3 on the power transformer.
15

PanelPreparation
Cut one 10” x 2” piece of damping material into two pieces: 10” x 1”.
Cut another 10” x 2” piece of damping material into three pieces:
Two, 8” x 1” and one, 2” x 2”.
Cut the remaining 10” x 2” piece of damping material into four pieces:
Two, 4” x 1”, one, 8” x 1” and one, 2” x 2”.
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BottomPanelPreparation

Note that the lip on the bottom panel points towards the inside.
1. Install the four feet in their holes close to the corners of the panel.
Use a 6-32 x ½” screw, flat washer and Kep nut on each foot.
Place the washer between the head of the screw and the rubber foot.
2. Install one piece of 8” x 1” damping material on the inside of the bottom panel, centered
between the vents and the lip.
3. Install one piece of 4” x 1” damping material on the inside of the bottom panel, next to and
centered on the left side of the vents.
4. Install one piece of 4” x 1” damping material on the inside of the bottom panel, about 1”
away from and centered on the right side of the vents.
Note that the bottom panel in the picture above has lines drawn to show where the transformer
and circuit boards will be mounted.
16

TopPanelPreparation
1. Place the top panel such that the inside surface of the panel faces up and the edge with the lip
(front) is away from you.
2. Install one piece of 10” x 1” damping material on the inside of the top panel, centered
between the vents and the lip.
3. Install one piece of 10” x 1” damping material on the inside of the top panel, centered
between the back of the panel and the vents, but closer to the vents so as not to interfere with
attaching the back panel.
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BackPanelPreparation

The back panel consists of two parts: an open frame that attaches to the other panels and a
customized insert that contains the jacks.
Place the insert inside the frame and secure them with ten 4-40 x ⅜” screws and ten Kep nuts.
Because two panels being clamped together inhibit vibration resonances, no damping treatment
is required for this panel.
————————————————————————————
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17

SidePanelPreparation
1. Install an 8” x 1” piece of damping material centered on the inside of the left panel.
2. Install an 8” x 1” piece of damping material centered on the inside of the right panel.
————————————————————————————
FrontPanelPreparation
The position of damping material for the front panel will vary depending upon the switches and
controls that you have chosen.
Install the two remaining 2” x 2” pieces of damping material on the inside of the front panel.
•Position them evenly and you may wish to cut one or both pieces to provide a more even
distribution.
•Make sure that there is at least ⅝” between the damping material and either the top edge
or bottom edge of the panel.
————————————————————————————
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18

PanelAssembly
BottomPanelAssembly
Steps preceded by a “note” (♪) deal with components which must be oriented properly.
TIP – To ease the alignment of the mounting holes with standoffs, slightly loosen the standoffs
from the board, install the screws through the bottom panel into the standoffs and then re-tighten
the standoffs.
————————————————————————————
♪
Mount the power transformer
1. Mount the LL1683 transformer in its location using the four 4mm metric screws. Orient the
transformer such that the high-voltage (shorter) pins are towards the front of the panel. The
front of the panel has the lip.
•Dress the white/black twisted pair toward the edge of the panel. Then the white/black
twisted pair will go towards the rear of the panel and the black/black twisted pair will go
to the front of the panel.
•Dress the grey twisted pair that will attach to the Power Output Module toward the edge
of the panel.
•If you have a second grey twisted pair that will attach to a Power Output Module, dress it
toward the edge of the panel.
•Dress the grey twisted pair that will power the filaments toward the center of the panel.
•Dress the red/red/black twisted trio toward the center of the panel.
19