Great timing as I have also been busy integrating my Bluetooth communications into my Peltor Optime III ear defenders. This cost about £90 in materials (Not including the helmet).
Here's a video from start to finish of the project:-
I went for a Excelvan 6 Riders bluetooth device which cost about £30, I have already been using this between myself and another paramotor pilot for about a year now. It has excellent range of nearly a mile and enables both pilots to have a full duplex conversation. The only down side is you can only have 2 people talking at once, unlike the Sena which can handle more. If you fly in close formation up to a mile then its crystal clear with no interference from the paramotor engine. However as a standalone device it is tricky to operate when you have thick winter gloves on and even without gloves, you really need to be able to see the buttons you are pressing. So I hacked it apart, took out the electronics and integrated them into my Peltor Optime III ear defenders.
This video documents some of the stages on how I went about integrating the bluetooth into my Peltors. It was a huge challenge, but with lots of patience and careful soldering skills I knew it was possible.
Here’s some of the items used in this project:-
1200M Bluetooth Interphone BT Motorcycle Helmet Intercom Headset Mic 6 Rider
This is the Bluetooth device that works perfectly well on its own, alternatively this device can be placed on a flight deck and you can’t really go wrong for about £30 on its own or £60 pair!
3M Peltor H540P3E Optime III Helmet Mounted Attachment Earmuffs Ear Defenders
These are the ear defenders used to integrate the Excelvan 6 Riders Interphone bluetooth device
12 core cable 7/0.22 Small Power or Data Cable (Overall Diameter 6.10mm)
This was used to connect both sides of the ear defenders to the bluetooth electronics.
2 SLEEVED BLACK PVC GROMMET 7.6mm HOLE MAX CABLE DIA 6.1mm
I used these to retain the 12 core cable in each ear defender.
3.5mm Mini Jack Chassis Panel Mount Stereo Headphone Input Socket Connector
This was used to extend the existing 3.5mm charging jack to the peltor ear defenders.
EBAY:- http://www.ebay.co.uk/itm/322081328156?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT Off(On) Momentary Push Button Switch Horn Doorbell Car Dashboard Dash 12V
4x Blue Buttons = For channels B to E
1x Black Button = For volume down
1x Red Button = For volume up
12V OFF (ON) Momentary Push Button Horn Switch Car Light Dashboard Boat SPST
1x Black = For off & reset
1x Blue = For the power on & Channel A
1x Green = For the phone/play
Glassfibre Sheet GRP Epoxy Glass G10 FR4 Fibreglass Sheet 12"x6"
This was cut to size to fit in each ear defender and position the speakers. I also cut a piece to size to super glue the electronics to it to keep the bluetooth electronics in the required position. I also used this to glue some terminal tabs for attaching the 12 core cable and small copper wire to each tiny button on the bluetooth electronics.
EBAY:- http://www.ebay.co.uk/itm/301153020803?_trksid=p2057872.m2749.l2649&var=600236590644&ssPageName=STRK%3AMEBIDX%3AIT NOTE:-
To do this project you will also need some important tools such as a drill for the button/wire holes, stanley knife, hacksaw and files to shape the fibreglass sheets and most importantly a decent soldering iron!