Well since getting a 3D printer I've finally managed to finish off the project and put it in a case, it's not often I actually put things in a nice case.
The first case with the Nokia display, it was a bit clunky and easy to break, when I dropped it that is!
Second attempt, this is the one I've been using. This one uses the Bluetooth module to talk to an app on the phone here
|Collection of bits held together with heatshrink|
|The end that screws on with the USB connector below and the front|
view with the on/off switch and battery charge connector
This one uses the Bluetooth adapter and connects to an app on the phone and has an internal lithium Ion battery than can be recharged using an external supply and charging module, you can leave out the battery and use the USB connector of the Nano to power the chronograph from your laptop or a battery pack with a USB power output. (if you do this then the switch doesn't do anything)
The enclosure is essentially two parts, a carrier, that holds all the electronics and a slide on cover.
Both parts are a push fit onto the aluminium tube (16mm Dia. x approx 100m long)
Parts list: -
|3D printed enclosure - Thingiverse||www.3dhubs.com
|£10 - £20|
|Arduino Nano (could be mini pro etc.)||Ebay||£2|
|Battery (Turnigy Nano-Tech 600mah 1S 3.7v 35-70C Lipo E-Flite)||Ebay||£5|
|Aluminium Tube - 16mm OD||Ebay||£5|
|3V to 5V converter (NCP1402-3.3V STEP-UP BREAKOUT)||Proto Pic||£4|
|JST wired plug connector||Ebay||£3 for 10 off|
|IR Emitter x 2||Ebay
RS= £2.25, 5 off
|IR Detector x 2||Ebay
|RS=£5, 5 off|
|Android App apk file (from Aptoide store)||Here||Free|
So around £44 to put together, £24 'ish if you can 3D print your own enclosure.
You could also do away with the battery and 3 to 5V converter if you powered it from you laptop USB or battery with a USB socket on it.
|Battery and PCB modules in place with the tube|
|Barrel end showing the USB connector|
|Front end showing on/off switch fitted|
|Inside the cover|
|The Bluetooth module wired to the Nano|
|Nano and BT module in the carrier|
|Everything wired up... nearly. 3 to 5V converter top left under the battery|
As usual feel free to ask questions and comment below.