VU Meter for LED Strip Lighting Alpha

VU Meter for White LED Strip Lighting Alpha

UPDATE:
The project is on hold at the moment. Many other better circuit designs have become available. However the design files for the shroud are still useful.

A major snag I have hit is the current rating on the LM914. Each output is only able to drive 20mA. Running a 3 LED strip will draw about 60-90mA, for this reason I have had to add transistors to each of the outputs. This has significantly complicated the conversion to a PCB. I have tried many options so far, including only driving 5 outputs and running the transistor LED drivers on their own mini boards as well. At this point I am not too sure where to go from here, the whole projects seems a bit untenable. I will upload new designs and images when I can get uploads working again.

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Gday All,
this is my first instructable.
It is a work in progress.

I am thinking it would rest on top of a smart phone perfectly!
Depending on where you drilled the lower two jiffy box mounting holes.

It is ALMOST big enough to hide a mac pro on your desktop!
http://arstechnica.com/apple/2014/01/two-steps-fo...

I am a High School Teacher in a Secondary School in South Australia.
I am currently developing an Electronics project for my year 11 (SACE Stage 1) course (15-17 year olds).
http://www.sace.sa.edu.au/web/design-and-technolo...

The schematic is currently under review by an electronic engineer (or two!).
More will be posted as the design develops.

Resources Required:
Roland MDX-40
http://www.rolanddga.com/products/milling/mdx40/
Will be used to cut the wooden faceplate, acrylic shrouds and PCB.
Everything apart from the PCB is created with a 6mm end mill.
The PCB will be machined with a 60 degree conical tool.

VCarve 7.0
http://www.vectric.com/products/vcarve-pro.htm
Will be used to cut the wooden faceplate and acrylic strips.
Tool paths are being optimized to reduce machining time.

Please note that the VCarve files provided do not yet have feeds and speed entered.

Circuit Wizard
http://www.new-wave-concepts.com/ed/circuit.html
Will be used to create the schematic diagram and PCB layout.

CopperCam
http://www.galaad.net/coppercam-eng.html
Will be used to mill the PCB on the Roland MDX-40A.

280mm Lengths of 140mm * 12mm Matchboard

Acrylic offcuts of a minimum size 108mm * 20mm * 3mm
(Machined with a 6mm tool using the Roland MDX-40)

Inspiring Resources for this Project:
http://circuit-diagram.hqew.net/Simple-Mic-Prehttp://circuit-diagram.hqew.net/Simple-Mic-Pre$2dAmp-based-LM358-circuit-diagram_4100.htmldA...

http://lowvoltage.wordpress.com/2011/05/21/lm358-m...

https://www.instructables.com/id/Led-VU-Meter-2/

http://oritoday.pp.ua/ori.php?v=ExqWAln9h2s&featur... or http://www.youtube.com/watch?v=ExqWAln9h2s

http://www.edutek.ltd.uk/Circuits.html#Audio

Circuit Wizard Built in Files-> Assistant:Advanced:Bar Graph Display

Current Dimensions:
Jiffy Box (UB3 to fit PCB 107mm * 62mm)
130mm * 68mm * 44mm

Wooden Face Plate
280mm *100mm * 12mm
(Roland MDX-40 Max Blank Material size is 305mm)

Acrylic Strips
12mm * 100mm * 3mm
(Minimum blank size milling strips using Roland MDX-40 is 108mm * 20mm)

Limited Parts Description:
LM348 (Operational Amplifier)
LM3914 (LED Dot/Bar LED Display Driver)

LED Loom:
It may be worthwhile looking at different cabling options for the LED loom.
A common anode on the LEDS makes the loom a whole lot simpler,
jumping from one anode to the next. Meaning the minimum number of wires
(and connections on the PCB) is 11. Rainbow Wire is usually 16 Core,
which makes it a very likely candidate for the LED loom, where you can use
the four leftover strands for wiring the LED anode, pots and switches.
(http://www.jaycar.com.au/productView.asp?ID=WM4516)

I am however thinking of using 10 pin terminals, which would mean that the
anode sits in a unique loom unto itself (10 + 1), perhaps the anode can be
connected on a single riser pin soldered to the PCB.

Wooden Faceplate Drilling Jig:
To match the holes on the jiffy box for the wooden faceplate,
I will only use the lower two holes.
The angle that it sits on, makes the top two fixing points redundant.

I am thinking of making up a jig with the Roland MDX-40,
that helps with the pilot hole drilling on the wooden faceplate (100mm),
to matchup with the jiffy box lid holes.
This will allow for the correct offset from the bottom edge,
when resting the VU meter on a particular model phone.

Acrylic Offcuts:
When using the Roland MDX-40 a maximum of approximately 80mm2
will be cut off as waste when machining a blank
(sized 108mm * 20mm). I implore that you use
two vacuum cleaners when creating this project
so that the the acrylic bag from the vacuum cleaner
can go to the recyclers. DON'T mix wood and acrylic
in your vacuum bags, it makes it harder for the recyclers.

It won't be long until the acrylic vacuum bag is used
to create your next 3D printed creation.

Moodle:

Below is a link to our Year 8-9 Electronics Moodle
http://dlb.sa.edu.au/rehsmoodle/course/view.php?i...

The following Electronics Moodles are under development:

Year 10 Electronics
http://dlb.sa.edu.au/rehsmoodle/course/view.php?id...

Stage 1 Electronics
http://dlb.sa.edu.au/rehsmoodle/course/view.php?i...

Stage 2 Electronics
http://dlb.sa.edu.au/rehsmoodle/course/view.php?i...