This is only a preview of the July 2008 issue of Silicon Chip. You can view 30 of the 104 pages in the full issue, including the advertisments. For full access, purchase the issue for $10.00 or subscribe for access to the latest issues. Items relevant to "DSP Musicolour Light Show; Pt.2":
Items relevant to "A PIC-Based Musical Tuning Aid":
Items relevant to "Balanced Mic Preamp For PCs & MP3 Players":
Items relevant to "Bridge Adaptor For Stereo Power Amplifiers":
Purchase a printed copy of this issue for $10.00. |
PT.2: By
MAURO GRASSI
DSP Musicolour:
putting it together
In last month’s first part, we described the circuit operation of the DSP Musicolour.
In this instalment, we guide you through the construction. The operation of the
firmware and troubleshooting tips will be described next month. In this issue there
are also notes and errata for the schematic published last month.
B
efore we start any construction, let’s make a couple of
things perfectly clear about the complexity and skill
levels needed to build the DSP Musicolour.
(1) This project is not suitable for beginners. In fact, you
should not attempt to construct this project without considerable experience, particularly with mains devices.
(2) This project controls mains (230/240V or 110/120V)
voltages. Mains voltage can be lethal. Hence it is especially
important to double check and be certain that mains power
is not applied whenever working with the PC boards. NEVER
apply mains power to the main PC board unless it is fully
enclosed in a plastic case with the case screws done up.
Construction: Display Board
The DSP Musicolour is built on two separate PC boards.
The main board consists of the Triac output section at
230/240VAC mains potential and the low voltage section
containing the op amps and the dsPIC30F4011 microcontroller. The two sections of the main board are isolated by
optocouplers and the mains transformer. The vertical display
24 Silicon Chip
board is all low voltage circuitry and its supply rail is +5V.
We’ll begin the construction with the display board, which
is coded 10107082 and measures 247mm x 76mm. Note:
our prototype DSP Musicolour used single-side boards with
many links, however kitset suppliers are likely to provide
the boards in double-sided form with plated-through holes,
in which case only a few links will be necessary.
First, you should check the PC board for hairline cracks
in the tracks and any visible shorts between tracks. Fix any
defects.
The component overlay is shown in Fig.1. The first components to go in are the resistors, 31 in total. As you install
them, check the colour code of each resistor against the
colour code table. Better still, check the values with a digital
multimeter before soldering each one onto the PC board.
The seven signal diodes can be soldered in next. It is vital
that they are oriented correctly and you should refer to the
component overlay and check carefully against it. The diode’s
cathode (K) is indicated by a line at one end of the body.
Next, solder in the four 16-pin IC sockets. Make sure these
siliconchip.com.au
The main and display boards assembled in the case, before the rear panel (and rear panel wiring) is fitted. This prototype
photo has single-sided PC boards – production boards should be double sided to eliminate most links. However, if you
etch your own PC board it will probably be as per the prototype and require links as shown above.
are oriented correctly as per the component overlay. Although
the sockets are optional, we do recommend them. They make
replacing the ICs much easier, if needed.
The sockets for the three Kingbright dot matrix LED
modules can now be installed. Cut three 14-pin IC sockets
in half with pliers to get six 7-pin sockets and solder them
in as shown on the component overlay.
The sockets are used to raise the dot matrix modules to
make them sit close to the acrylic front panel. They also make
replacing the modules much easier if they should ever fail.
Once this is done, you can solder in the 22 BC327 transistors. These are all PNP types and should be pushed down so
that they sit quite close the board in order to clear the front
panel. However, be careful not to push them too close, as
this may damage the leads. About 2mm proud of the board
surface is ideal.
Next, you can solder in the three 10kW potentiometers
and the capacitors. The three 100nF monolithic types are
placed near the IC sockets for the 74HC595 shift registers
(IC3, IC4 & IC5). The two electrolytics are placed near VR3
and must be installed the right way around. Their negative
terminals are indicated on their bodies and you should refer
to the component overlay before you solder them to ensure
they are correctly in place.
The 26-pin IDC (insulation displacement connector)
header (CON7) can be soldered in next and you should
refer to the component overlay to get the correct orientasiliconchip.com.au
tion. Note that there is a key-way on one side of the socket.
Pin 1 of the header should be indicated by an arrow in the
plastic socket.
Finally, solder in the seven vertical tactile switches which
have LEDs inside. There are three red and four blue switches.
These switches have six leads arranged in two rows of three.
The middle leads in each of the two rows are used to connect
Warning!
All the parts in the red shaded area
on the Main Board
component layout diagram (Fig
.3) operate at mains potential (ie, 240VAC) and contact
with any of these parts
could be FATAL.
These parts include the PC trac
ks, the opto-couplers
(OPTO1-4), the Triacs, the 100
mH inductors, the 680W
resistors, the 100nF 250VAC capa
citors, screw terminal
blocks CON4-CON6, the transformer
primary and the wiring
to the mains input and output sock
ets. DO NOT TOUCH any
of these parts unless the power cord
is unplugged from the
mains supply. DO NOT CONNECT
this device to the mains
unless it is fully enclosed in the
specified case.
This project is not for the inexperi
enced. Do not build
it unless you know exactly wha
t you are doing and are
completely familiar with mains
wiring practices and construction techniques.
July 2008 25
100nF
Q4
LED ARRAY 3
Q1
LED ARRAY 2
Q6
470Ω
Q9
Q10
470Ω
Q12
470Ω
Q13
470Ω
Q11
Q15
470Ω
Q14
470Ω
470Ω
470Ω
470Ω
470Ω
100nF
100nF
470Ω
IC1 74HC595
IC2 74HC595
1k
S1
S2
S3
VR2
10k LIN
YALPSID RUOLOCISUM
28070101 CS
Q21
S6
1k
47 ∝F
D7
470Ω
D6
Q16
D5
S5
Q20
4148
470Ω
S7
VR1
10k LIN
470Ω
+
1k
1k
4148
D1
4148
4148
VR3
10k LIN
470Ω
S4
Q19
1k
470Ω
+
1 ∝F
D4
1k
Q17
D3
4148
470Ω
D2
4148
1k
4148
8002/30 GM
Q18
Q22
Links LK1, LK2 & LK3 need to be installed, depending on whether
you will be powering the DSP Musicolour from 110-120VAC or 230240VAC. If you are in Australia, New Zealand and most parts of Europe,
you will be using 230V-240V while 110V-120VAC is used in America
and Japan, for example.
For 230-240V operation, you should install link LK2 and leave out
LK1 and LK3, under the transformer. For 110-120V operation, you
should install links LK1 and LK3 and leave out LK2.
LED ARRAY 1
Q8
Links for 230/240VAC or 110/120VAC operation
TA12-11EWA
Q7
470Ω
Assembling the main board
The main board is coded 10107081 and measures 221mm x 165mm.
The component overlay is shown in Fig.3.
Again, begin the construction by checking the copper pattern for
defects such as track breaks or shorts. Fix any defects that may be
apparent.
74HC595
TA12-11EWA
470Ω
Attaching the front panel
The final task is to attach the acrylic front panel. The four mounting
holes are used to attach the front panel to the display board using four
M3 Nylon screws (25mm).
You will need to cut off 2mm from four 15mm tapped Nylon spacers
to make them measure 13mm. This is the correct spacing between
the display board and the front panel that fits with the grooves in the
plastic case (Altronics H0482).
Finally cut the remaining four 15mm tapped Nylon spacers to 4mm
and use these as the nuts to attach the front panel. Then simply attach
the three knobs to the potentiometers and that should complete the
assembly of the display board.
IC3
TA12-11EWA
470Ω
Q5
This completes the construction of the display board. The last
thing to do is to make up the ribbon (IDC) cable used to connect the
display board to the main board. To do this, you will need a vise.
Cut 15cm of 26-way ribbon cable and slide it into position into each
26-pin IDC line socket. Conductor 1 of the ribbon cable is indicated
by a different colour – usually the ribbon cable is grey and conductor
1 is red. This should match pin 1 of the line sockets, indicated by
arrows. You should slide the ribbon cable into place and then use a
vise to attach the cable.
Finally attach the clip to only one line socket leaving the other one
without one. The line socket for the display must not have a clip attached, in order to clear the front panel.
Once you are satisfied that everything is in order, you can insert
the ICs into their sockets, making sure that they are correctly aligned.
Then insert the three Kingbright dot matrix LED modules into their
sockets. Make sure that pin 1 of the Kingbright modules is facing down
as indicated on the component overlay. The modules should show a
digit ‘1’ indicating pin 1.
470Ω
Q3
Ribbon cable assembly
IC4 ULN2003
Q2
the internal LED and you should make sure that they are oriented correctly, otherwise the LED will not light up.
For each switch, the cathode is indicated by a dab of coloured paint
on the lead with the colour matching the colour of the LED inside the
switch. The switch should be soldered with the cathode facing up in
the normal orientation. Switches S1-S3 should be red while switches
S4-S7 should be blue. Note that this differs from the prototype photos
shown here and in last month’s article.
1k
1k
470Ω
Fig.1: component overlay for the display PC board with a matching
photo opposite. Start assembly with the display PC board as detailed
in the text. The top layer of the PC board is shown in green – if you
etch your own (single-sided) board, the green tracks will need to be
replaced with wire links, with holes drilled in appropriate places.
26 Silicon Chip
25
26
1
2
CON7 (CONNECTS TO CON1 ON MAIN BOARD)
siliconchip.com.au
You must never install all three links LK1, LK2 and LK3 at the same
time. This will short the mains supply and blow the fuse and possibly
trip the circuit breakers in your home!
Make sure you have installed LK2 (for 230-240V) or LK1 and LK3
(for 110-120V) correctly before proceeding.
There is an optional link near the two 270W 1W resistors and CON2.
This is shown as LK4 on the main circuit (Fig.2) in last month’s issue
and this will normally be omitted. Its operation will be explained in
next month’s article.
Next, you can move on to installing the resistors. Again, check each
value against the component overlay diagram of Fig.3 , the colour code
table and with your digital multimeter.
There are seven diodes on the board and it is vital that they are
oriented correctly. Diodes D11-D14 are 1N4004 while D8-D10 are
1N4148. Notice that diodes D11-D14 (the bridge rectifier) are not all
oriented the same way (their orientation alternates).
Once the diodes are in, you can solder in the two IC sockets; the
40-pin socket for IC1and the 16-pin socket for the LM324 quad op amp
(IC2). Make sure these are oriented correctly as per the component
overlay.
Next, solder in the four optocouplers (MOC3021). These are 6-pin
devices and it is vital that they be oriented correctly, with their pin 1
on the low voltage side of the board.
The capacitors go in next. The MKT and monolithic capacitors are
not polarised but the electrolytic capacitors are and you should refer
to the component overlay to install them correctly.
The four 100nF X2-type 250VAC capacitors on the mains side of
the board should be soldered in so they are sitting flush, ie, without
any of their leads being exposed.
Next, to install the LM317T regulator REG1, bend the leads by 90°
before threading them through the holes on the board. Then fasten the
tabs to the TO-220 mini heatsink and to the main board using one M3
10mm screw and one M3 nut. Do this before soldering the leads, as
the stress of tightening the tab could cause cracks in the solder joints
if the regulator is soldered in first.
The 3mm red LED (LED8) can be installed next. This must be oriented correctly with its flat side as shown on the(HEATSINK)
component overlay.
LOCK
The two 2-pin jumpers labelled M3
LK5
and LK6 on the component
SCREW
WASHER
10mm terminal strip and soldered
overlay can be made from the 28-pin header
LONG
in. They will accept optional jumper shunts.
You should also take two single pins from the 28-pin header terM3 NUT
minal strip and solder these in for the two test points TP0 and
TP1,
near regulator REG1. The test pointsBTA41-600B
will be used to measure the
input
BTA41-600B
TRIAC
and output of the regulator, as will be TRIAC
explained below. After that
you
can install the electret microphone insert, again making sure that it
is oriented correctly.
Next, install the 26-way IDC header, as shown on the component
PC BOARD
(HEATSINK)
M3 SCREW
10mm
LONG
BTA41-600B
TRIAC
HEATSINK
LOCK
WASHER
M3 NUT
BTA41-600B
TRIAC
BTA41-600B
TRIAC
M3 SCREW
10mm
LONG
LOCK
WASHER
M3 NUT
BTA41-600B
TRIAC
PC BOARD
HEATSINK
Fig.2: elevation
(left) and plan (right) views of the way the Triacs are
mounted to the double-sided heatsinks (two Triacs to each heatsink).
Use an M3 metal screw (10mm) and an M3 nut.
siliconchip.com.au
BTA41-600B
TRIAC
M3 SCREW
10mm
LOCK
WASHER
M3 NUT
July 2008 27
OPTIONAL
LINK
D10
TNORF
1 8 0 7 0 1 0 1 CS
LK2 240V
JP1
LK1 120V
+
+
CABLE TIES
L4 100 µH
TRIAC1
TRIAC3
TRIAC2
TRIAC4
100nF
100nF
250VAC 250VAC
X2
X2
RE G NAD
E GATL OV S NIA M
CON4
CABLE TIES
100nF
250VAC
X2
L1 100 µH
100nF
250VAC
X2
L2 100 µH
CON6
N
MAINS
110V-240V
N
A
A
V 0 5 2-V 0 2 1 S NIA M
CON5
K
CA B
BACK
Fig.3: component overlay for the main board, which includes all the mainspotential circuitry (apart from the input/output IEC sockets). The top
(component) side of the PC board is shown with green tracks; the bottom side
in the usual copper colour. The dotted area above shows the section of the PC
board which has components and tracks at mains potential. Never operate the
DSP Musicolour unless it is inside its case with the lid screwed on.
siliconchip.com.au
WARNING: All parts in this section operate at 230/240V.
WARNING!
DO NOT FIT
ALL THREE
LINKS AT
THE SAME TIME
680Ω
680Ω
680Ω
680Ω
JP3
LK3 120V
JP2
PRIMARY
PRIMARY
L3 100 µH
8 0 0 2/ 4 0 G M
RU OL O CISU M
OPTO1
240V: FIT LK2 ONLY
120V: FIT LK1 & LK3 ONLY
OPTO 1–4:
MOC3021
TRANSFORMER
T1
30VA 7.5V
+
MIC
220Ω
OPTO2
REG1
LM317T
100Ω
TPI
TP0
100Ω
100Ω
100nF
4.7k
220Ω
220Ω
220Ω
OPTO3
FRONT
+
470 µF
D11
D12
D13
D14
1 µF
D9
47 µF
SECONDARY
SECONDARY
L O SI
E NIL N OITALINE
ISOLATION
OPTO4
CON1
470Ω
4700 µF
16V
4148
5.6nF
10k
10k
47 µF
100Ω
1
2
10k
100k
100nF
D8
LED8
100nF
270 Ω 1W
1k
4148
dsPIC 30F4011
LK5 LK6
9
10
+
1k
CON2
270 Ω 1W
33k
3.3k
68nF
28 Silicon Chip
+
IC2 LM324
68nF
At this stage it is prudent to go back
over your work and make sure everything looks in order by comparing your
populated board with the component
overlay.
If you are absolutely satisfied that you
have installed or omitted LK1, LK2 and
LK3 as per the instructions (depending
on the mains voltage in your area), you
can solder in the mains transformer.
This should only fit one way and its
primary and secondary sides should be
10k
33k
68nF
Final main board construction
IC1
1k
68nF
Once that is done you are ready to solder in the four Triacs. It is most important
that these be insulated tab types, which
is why BTA41-600B are specified. You
should use a multimeter and measure
the resistance from pin 2 (the middle
lead) of each of the four Triacs to their
metal tabs. This should indicate a very
high resistance or open circuit. On the
other hand, if it indicates a low resistance or short circuit you probably do not
have the correct Triac and you should
not proceed.
Once you have verified that the Triacs
have insulated tabs, attach two to each
double-sided heatsink using an M3 10mm
screw and M3 nut as shown in Fig.2.
Notice that the tabs of the Triacs are in
direct contact with the heatsink.
It is then a matter of sliding the heatsink with the two attached Triacs onto the
PC board. The heatsink has two mounting
pins to locate them on the PC board. You
can then solder the two Triacs in place.
Repeat this for the other pair of Triacs.
The construction of the main board is
now complete as regards to soldering in
components. The only component missing is the potted transformer.
1k
4148
CON3
Installing the Triacs
270 Ω 1W
overlay. This has a keyway on its side
which should face the microcontroller.
CON2 consists of a 2-way and a 3-way
mini terminal block slotted into each
other to make a 5-way terminal block.
Two 2-way terminal blocks CON4
and CON5 and the 3-way terminal block
CON6 should be soldered in next. Their
screw terminal inputs should be facing
the BACK edge of the main board.
You can also solder in the four 100mH
chokes (these must be rated at 5A) which
sit vertically on the main board. As these
are wound with enamelled copper wire,
you should ensure that the terminals
have been properly stripped and tinned
before you attempt to solder them in
place.
clearly marked. The secondary side should
point towards the low voltage side of the
circuit while its primary side should point
towards the two heatsinks holding the four
Triacs.
You should attach the transformer to the
main board using an M4 screw before soldering the leads. The screw will need to be
threaded from the copper side (bottom side)
of the board and holds the heavy transformer
in place (the screw hole is the one in the
middle of the transformer just to the left of
LK3 on the component overlay). Now solder
the transformer in place.
Installation instructions
>1mm
ENAMELLED
COPPER
WIRE LINKS
(FOR S/S
PC BOARD
ONLY)
This prototype photograph matches the overlay at left, with the exception of
most of the wire links which have now been replaced by tracks on a double
sided board. Again, if you etch your own single-sided board, the links will
be required. In the case of the two heavy enamelled copper wire links in the
mains section of the board (arrowed above), make sure you use similar heavy
enamelled copper wire – for safety’s sake!
siliconchip.com.au
If you have followed these instructions,
you should now have an assembled display
board with its four ICs in their sockets and a
26-way ribbon cable plugged into it with its
other end as yet unconnected. You should
also have an assembled main board with
all components soldered and with IC1 and
IC2 out of their sockets for now.
Notice that the case is not symmetrical and so the main board has indicators
“FRONT” and “BACK” on the component
overlay, indicating the back and front
panels.
Attach the main board to the case using
the four mounting holes and M3 10mm
screws. The two lower screws attach directly to the case (Altronics H0482) while
the top two screws should be attached using
two 3mm x 15mm Nylon spacers, cut to
8mm long and with longer M3 Nylon 25mm
screws. The spacers are used to provide
support to the main board when it is in the
case. You will need to drill two 3mm holes
in the bottom of the plastic case to thread
these through as shown in Fig.7. You can
then attach them to the PC board using M3
nuts (also shown in Fig.7).
Once the main board has been attached
to the case, continue by installing the appropriate fuse inside the male IEC socket
– 10A (for 230-240V operation) or 15A (for
110-120V operation).
You will now need to make up some
connections for the back panel, using the
individual cables from the 1m length of
three-core mains flex cable, spade lugs
and a crimping tool. (The three-core
mains cable is used to ensure sufficient
voltage rating for these mains-carrying
connectors).
First remove the outer insulation from
the three-core mains flex and use the
brown, blue and green/yellow wires, following Fig.4, which details the lengths
of the wires you need to make. These
are labelled W1 to W9 in Fig.4 and these
numbers will be referred to below.
July 2008 29
The rear panel of the DSP Musicolour sports the IEC power input socket with integral fuse and mains switch (far right),
the four IEC controlled output sockets (centre), 6.5mm audio input socket and stereo audio (speaker level) input sockets
(far left). If the speaker level input sockets are used, they’re designed to go in parallel with existing speakers.
50mm
All these crimps need to be done carefully to ensure the
connections are tight between the spade lugs and the wire.
Don’t be tempted to use an automotive-type crimper – they’re
not strong enough to produce a quality crimp and your wires
could come out of the spade lugs. You need a good quality
ratchet-type crimper and good quality spade lugs.
W1:
40mm
W2:
80mm
80mm
80mm
80mm
Back panel installation and wiring
90mm
MATES WITH
'N' TERMINAL
OF CON6
W3:
(IECF4)
(IECF3)
(IECF2)
(IECF1)
MATES WITH
'A' TERMINAL
OF CON6
(IECM1)
90mm
W4:
(IECM1)
W5:
80mm
TO SPADE
CONNECTOR
UNDER EARTH
SCREW ON
BACK PANEL
80mm
(IECM1)
80mm
(IECF1)
80mm
(IECF2)
80mm
(IECF3)
120mm
(IECF4)
MATES WITH
TERMINAL 5
OF CON2
120mm
W6:
OC1
(CON5)
(IECF1)
120mm
W7:
OC2
(CON5)
(IECF2)
150mm
W8:
OC3
(CON4)
(IECF3)
200mm
W9:
(IECF4)
OC4
(CON4)
Fig.4: you will need to make up several crimped
connector cables for the DSP Musicolour. This diagram
shows the various types, colours and lengths.
30 Silicon Chip
The back panel is made of steel and kits should be supplied
with all holes punched and drilled. Snap in the male IEC socket
(with the fuse installed as explained previously) and the four
female IEC sockets as well as the optional microphone jack
and audio speaker terminal block. The audio speaker terminal
block is attached using two Nylon M3 12mm screws with two
3mm x 6.3mm nylon spacers used as nuts.
Next, install the “earth” spade lug on the back panel using
an M3 x 10mm screw, shakeproof washer and two nuts (see
Fig.5). These will be used to earth the back panel later on.
Check with a DMM that the screw is electrically connected to
the back panel (ie, 0W or very close). You may have to scrape
some paint away under the nuts to ensure intimate contact.
Install the back panel in the case and use the display board
with its attached plastic front panel as the front panel (but
without yet connecting the display board to the main board
using the 26-way ribbon cable).
Install W1-W9 as shown in the wiring diagram for the back
panel (see Fig.6). The insulated spade lugs are colour coded
so that the brown should indicate live (Active) while blue
indicates the Neutral mains connection. A green/yellow cable
is used for the Earth connection. Follow the wiring diagram
carefully to complete the wiring of the back panel.
You should be left with seven loose wires from W1-W9.
One green and yellow end of W5 connects to pin 5 of CON2 as
explained below in the section on Earthing. The other 6 loose
ends of W3-W9 connect to CON4, CON5 and CON6 terminal
blocks as shown in the wiring diagram Fig.6.
Make all these connections, paying particular attention to the
earthing instructions below. Also, use the holes on the main
board for attaching these wires solidly to the main board using
cable ties. Also use cable ties around each of the three wires
connecting to each female IEC socket. This is particularly
important to hold the wires in place, especially since two of
the female IEC sockets sit above the low voltage part of the
main board. Should the live connection to one of these come
off, the cable ties should ensure that they do not fall onto the
siliconchip.com.au
DSP Musicolour Parts List
Main Board and hardware
1 PC board, coded 10107081, 221mm x 165mm
1 Case (Altronics H0482) with steel panel punched for
IEC sockets
1 transparent red acrylic front panel, 254 x 75 x 3mm
with silk-screen labelling and drilled to suit
1 30VA 120V-240V 7.5+7.5V Potted Toroidal transformer (Altronics M4615)
1 Chassis Male IEC socket with switch and fuse (Jaycar PP4003)
1 IEC female power lead 240VAC (Jaycar PS4106)
4 IEC male to 3-pin (GPO) socket (Jaycar PS4100)
(optional)
4 Chassis Female IEC sockets (Jaycar PS4002,
Altronics P8327)
1 3AG 10A fast blow fuse (Jaycar SF2204)
1 26-way IDC header
1 10-way right-angled IDC header (optional)
1 0.15m x IDC ribbon cable 16-way (Jaycar WM4502)
(optional)
2 IDC line sockets 10-way (Jaycar PS0984) (optional)
3 2-way Mini PCB Terminal Block –5mm spacing
(Jaycar HM3173, Altronics P2032A)
2 3-way Mini PCB Terminal Block – 5mm spacing
(Jaycar HM3172, Altronics P2033A)
7 6.4mm blue insulated spade lugs (Jaycar PT4625)
7 6.8mm red insulated spade lugs (Jaycar PT4525)
5 6.8mm yellow spade lugs (Jaycar PT4707)
1 1m 3-core mains flex 10A (Jaycar WB1562)
Wire for connecting audio socket
1 6.5mm audio mono chassis socket (Jaycar PS0162)
1 4-way audio speaker terminal block (Jaycar
PT3002)
1 40-pin IC socket
1 16-pin IC socket
6 M3 screws 10mm long
1 M4 screw 10mm long
7 M3 nuts
2 Nylon M3 screws 12mm long (Jaycar HP0140)
2 Nylon M3 screws 25mm long (Jaycar HP0142)
4 Tapped Nylon spacers 3mm x 6.3mm (Jaycar
HP0920)
2 Heavy Duty TOP-3 (ML97 type) heatsinks (Jaycar
HH8526)
1 TO220 Mini (6073B type) heatsink (Jaycar HH8502)
2 Jumper shunts (Jaycar HM3240)
1 28-pin header terminal strips (Jaycar HM3211)
1 1m Tinned copper wire (Jaycar WW4032)
1 0.15m Enamel copper wire (1mm thick) (Jaycar
WW4022)
1 electret microphone insert (Jaycar AM4011)
4 100uH 5A toroid suppression chokes (Jaycar
LF1270) (L1-L4)
3 push-on 18T spline knobs to suit (Jaycar
HK7730/31/32; Altronics H6510)
1 dsPIC30F4011 microcontroller IC (IC1),
programmed with 1010708A.HEX
1 LM324 quad op amp (IC2)
4 BTA41-600B insulated tab Triacs
4 MOC3021 optocouplers
3 1N4148 diodes (D8-D10)
4 1N4004 diodes (D11-D14)
1 3mm red LED (LED8)
Semiconductors
1 LM317T 3-pin adjustable voltage regulator (REG1)
Resistors (0.25W, 1%)
22 470W
9 1kW
siliconchip.com.au
siliconchip.com.au
Capacitors
1 4700mF 16V electrolytic
1 470mF 16V electrolytic
2 47mF 16V electrolytic
1 1mF 16V electrolytic
4 100nF 250VAC X2 style 15mm pitch metallised
polypropylene (Jaycar RG5236)
3 100nF monolithic
4 68nF MKT
1 5.6nF MKT
Resistors (0.25W, 1%, unless specified)
4 100W
4 220W
3 270W 1W
1 470W
4 680W
4 1kW
1 3.3kW
1 4.7kW
4 10kW
2 33kW
1 100kW
Display Board
1 PC board, coded 10107082, 247 mm x 76 mm
3 Kingbright TA12-11EWA red 5x7 dot matrix LED
modules (Tenrod TA12-11EWA)
3 9mm 18T Spline Shaft Single Rotary Pots 10kW
Linear (Altronics R1946)
3 SPST Vertical PC mount tactile switch with LED
(red) (Jaycar SP0612, Altronics SS1174)
4 SPST Vertical PC mount tactile switch with LED
(blue) (Jaycar SP0614, Altronics SS1177)
1 26-way IDC header
4 16-pin IC socket
3 14-pin IC socket (cut in half)
4 Nylon screws M3 25mm (Jaycar HP0142)
8 tapped Nylon spacers 3mm x 15mm (Jaycar
HP0926)
1 0.15m x IDC ribbon cable 26-way (Jaycar WM4504)
2 IDC line sockets 26-way (Jaycar PS0987)
1 2m tinned copper (Jaycar WW4032)
Semiconductors
3 74HC595 shift registers (IC3-IC5)
1 ULN2003 line driver (IC6)
7 1N4148 diodes (D1-D7)
22 BC327 PNP transistors (Q1-Q22)
Capacitors
1 47mF 16V electrolytic
1 1mF 16V electrolytic
3 100nF monolithic
July 2008 31
K CA B
(W1)
RE G NAD
(W5)
(W6)
E GATL OV S NIA M
IECM1
(W3)
CABLE TIES
CABLE TIES
(W4)
IECF1
(W7)
(W8)
IECF2
+
(W9)
IECF3
+
+
1
2
+
IECF4
9
10
CON3
Preliminary power supply check
1
SIG GND
(W5)
4
(W3)
3
R IN
MIC IN
L IN
MIC IN
CON2
2
5
RIGHT
LEFT
STEREO
SPEAKER
INPUT
Once you have done that it is time to
check the power supply rails before final
assembly. To do this solder two wires to
the two test-point stakes (TP0 and TP1)
near REG1 and use pin 1 of CON2 as the
GND reference. The wires should be long
enough to leave the case and be accessed
from outside the case. You can thread
them through the hole used to mount the
microphone jack on the back panel.
Now close the case – attach the top half
and screw in the two screws to seal it.
(W2)
(W3)
CRIMPED
QUICK
Connect the
CONNECTOR
TO SPADE LUG
green/yellow
earth wire (W5) M3 X 10mm
TO
IEC
as shown in the SCREW AND
MAINS
TWO NUTS
wiring diagram
INPUT
SOCKET
in Fig.6 so that
the earth of the
male IEC socket
M3 STAR WASHER
connects to the
earths of all the Fig.5: the green/yellow
female IEC sockets earth wire must be
and the crimped securely connected to
connector which the back panel via a
is fastened to the crimped spade connearthing screw on ector and an M3 screw
the back panel, with two nuts and a
star washer.
as shown at right
(Fig.5). The remaining end of W5 should connect to pin
5 of CON2 (the 5-way terminal block) as
shown in Fig.6.
Do not proceed unless you are satisfied
that W5 connects all these points to the male
IEC socket’s earth terminal (the middle terminal). Again, you should use a multimeter
or continuity tester to make sure that all
these points (including chassis earth) are
electrically connected (0W or very close).
V 0 5 2-V 0 2 1 S NIA M
EARTH
(MAIN PC
BOARD)
CON4
OC3 OC4
MUSICOLOUR
BACK PANEL
CON5
Earthing
OC2 OC1
low voltage section of the main board.
Once you have attached the cable ties
as shown in Fig.6 and the photographs
you should proceed to the earthing section
below.
A
mF Code IEC Code EIA Code
0.1mF
100n
104
0.068mF
68n
683
0.0056mF
5n6
562
CON6
Value
100nF
68nF
5.6nF
N
Capacitor Codes
Fig.6: here’s the other side of the back panel, showing the wiring between the IEC
mains input socket/fuse/switch (top in this diagram), the four IEC female output
sockets (IECF1-4) and the PC board. Note carefully the position of the earth wire.
Not shown here are the cable ties around all the cables coming from the IEC sockets
(male and female). These are important safety items and should not be overlooked (see photo above right).
32 Silicon Chip
siliconchip.com.au
Looking from front to rear, the mains wiring can clearly be seen. All wiring here is mains-rated – the easiest way to ensure
this is to use lengths of cable stripped from a scrap of mains-rated flexible lead. Don’t forget the cable ties: they’re just in case!
You should only proceed if the case is closed, the back and
front panels have been installed, the back panel has been
wired correctly as shown in Fig.6 and the back panel has
been properly earthed as explained above. Notice that the
display board is not yet connected to the main board using
the 26-way ribbon cable and that IC1 and IC2 on the main
board are out of their sockets still. Also the audio terminal
block and the microphone jack on the back panel are not
yet connected.
You can then apply power using an IEC power cable and
flicking the switch on the male IEC socket to the ON position.
You should measure the voltages at TP0 and TP1 relative to
the GND wire using a multimeter.
Normal levels should give around +10V DC on TP1 and
+5V DC on TP0. If the level on TP1 is not close to +10V
you should disconnect power immediately and recheck
your work.
If the voltage at TP0 is close to +5V it indicates that you
are on the right track. If the voltage at TP0 is much different
from +5V (note that anything from +4.8 to +5.2V is actually
OK) then there is something wrong and you should recheck
your work. Check the diodes D11-D14 are oriented correctly.
Check that REG1 is correct and the resistors associated with
REG1 are indeed 100W. Check that the large 4700mF electrolytic is correctly installed and that all the other electrolytics
are correctly oriented according to the component overlay.
Final Assembly
If (and only if) the voltages at TP0 and TP1 are OK, then
proceed. First switch off mains power and disconnect the
mains cord. Once you are absolutely certain there is no mains
power being supplied, open the case. Unsolder the two wires
attached to TP0 and TP1 and also remove the GND connection at pin 1 of CON2. These are no longer needed.
Install IC1 and IC2 on the main board IC sockets. Make
sure they are oriented correctly. IC1 should be programmed
with the latest version of the firmware. If you are building
the DSP Musicolour from a kit, IC1 will be pre-programmed.
If you are not, CON3, the optional10-way IDC header can be
used to program IC1 using an external connection. More on
this next month.
Now connect the audio speaker terminal block by soldering
Resistor Colour Codes
o
o
o
o
o
o
o
o
o
o
o
siliconchip.com.au
No.
1
2
4
1
1
13
4
23
3
4
4
Value
100kW
33kW
10kW
4.7kW
3.3kW
1kW
680W
470W
270W (1W)
220W
100W
4-Band Code (1%)
brown black yellow brown
yellow yellow orange brown
brown black orange brown
yellow violet red brown
yellow yellow red brown
brown black red brown
blue grey brown brown
yellow violet brown brown
red violet brown brown
red red brown brown
brown black brown brown
5-Band Code (1%)
brown black black orange brown
yellow yellow black red brown
brown black black red brown
yellow violet black brown brown
yellow yellow black brown brown
brown black black brown brown
blue grey black black brown
yellow violet black black brown
red violet black black brown
red red black black brown
brown black black black brown
July 2008 33
four wires onto the audio speaker terminals and connecting
them to the terminal block CON2. Also solder wires to the
microphone jack and connect these to CON2. Fig.6 shows
this connection (among others).
Connect the 26-way ribbon cable from the display board
to the main board (CON1 on the main board). The photo
overleaf shows the completed assembly (showing an early
but similar prototype) just before closing the case.
Close the case of the lid and screw it shut. Your DSP Musicolour is now fully assembled.
In next month’s article we will explain the user menus
and the operating instructions for the DSP Musicolour as
well as calibration instructions. Stay tuned.
SC
77.5mm
75mm
94mm
(FRONT)
(REAR)
LOWER HALF OF CASE
(VIEWED FROM BELOW)
78.5mm
(REAR
SMALL SELF-TAPPERS
PANEL)
SCREWING INTO
MOULDED STANDOFFS
M3 NYLON SPACERS
CUT TO 8mm LONG
M3 NUTS
(METAL)
(FRONT
PANEL)
MAIN PC BOARD
(BOTTOM OF CASE)
25mm M3
NYLON SCREWS
Fig.7: this scaled drawing shows how the main board is
secured in the case (note the use of Nylon spacers and
screws for safety).
DSP Musicolour Notes and Errata
In the Main Board schematic on pages 34-35 of the May 2008 issue, there are a number of minor errors. The labels P6C and P6D on
pins 26 and 25 of IC1 should read PGC and PGD. The labels TRIAC2
and TRIAC3 should be swapped and pin 18 (OC2)‑ of IC1 actually
connects to OPTO3 while pin 22 (OC3) connects to pin 1 of OPTO2.
In the Display Board schematic published on page 37, there is an
extra 470W resistor shown immediately to the right of pin 7 (Q7)
of IC4. This resistor is not required – the component overlays and
parts list in this issue reflect this.
34 Silicon Chip
siliconchip.com.au
|