virtual sqrls hardware
bnewbold, git repository
Basic Design
Arduino microcontrollers output audio via PWM method (see links). Signal is
amplified by audio amp then output to speaker over variable length cables. 4
potentiometers per board allow adjustment of volume, timing, and two
software adjustments. There are two amps/speakers for each arduino and 5
arduinos total. Each board/package is powered by a 5v wall wart.
Notes
Arduinos and protoboards were chosen in the interest of time and reusability;
the cost will be about $37 each for those units (could drive at least 4
speakers each if they had to?); chosing cheaper components like PICs and
plain grid boards could bring the cost down to $10-15 but would require a lot
of design, assembly, debuging, and would not be as easily reused afterwards.
The number of power supplies could be reduced if we ran power wires between
the units.
The amount of "power wire" will depend on the physical situation, but this
should be super cheap and we could get more at a hardware store last minute.
This all assumes tools and consumables like solder are availble (I have plenty).
Parts list
N is the number of distinct microcontoller "units" (5?); M is the
number of speakers with distinct outputs (5?). I say +1 on the cheap stuff in
case something breaks or gets lost.
|
How many | What | Specific Part |
Cost Each (rounded) |
From where |
|
| 5
| Motion Sensors
| Parallax PIR Sensor Module
#555-28027
|
| Mouser
(already purchased)
|
| 5
| Arduino Pro Board
| 328 5v/16MHz DEV-08943
(sparkfun version)
| $20
| Sparkfun (link)
|
| 5
| Arduino Protoboard
| DEV-07914
(sparkfun version)
| $17
| Sparkfun (link)
|
| 5
| Straight Pin Headers, 40x1
| PRT-00116
(sparkfun version)
| $2.50
| Sparkfun (link)
|
| 1
| FTDI-USB Breakout (Programming)
| DEV-09115
| $14
| Sparkfun (link)
|
| 5
| Wall Power supply (AC to 5v DC)
| EPS050100-P5RP
| $7.25
| Digikey(link)
|
| ??ft
| Power wire (high gauge)
|
|
| Radioshack?
|
| 10
| Speaker
| 4ohm 3watt
COM-09149 (sparkfun)
| $2.50
| Sparkfun (link)
|
| 11
| Audio Amp (5v)
| 5w stereo 12pin
Panasonic AN17822A
| $2.25
| Digikey (link)
|
| 21
| Adjustment Potentiometers
| 10k Ohm through-hole mount
EVN-D8AA03B14
| $0.40
| Digikey (link)
|
| 3
| Rolls of stranded wire
| 25ft each of Black, Red, White, 22awg
| $2.50
| Sparkfun (link)
Total cost estimate: $300
Useful Links
http://www.arduino.cc/en/Main/ArduinoBoardPro
http://www.sparkfun.com/commerce/product_info.php?products_id=9219
http://www.uchobby.com/index.php/2007/11/11/arduino-sound-part-1/
http://www.k9spud.com/traxmod/pwmdac.php
http://www.arduino.cc/playground/Code/PCMAudio
Helpful Emails
haha there are none!