As part of our Industrial design module in university we were given the brief of hacking a basic handheld radio (sony icf-s22) with the view to designing a radio for a specific user. I chose to design a handlebar mounted radio for a motorcyclist that would connect wirelessly to a headset within the helmet. This is how I did it.
Step 1: You Will Need..
(1) A basic radio - For this I used the sony ICF-S22 (£9.98 on amazon I think?)
(2) A Transmitter to wireless headphones - I found an incredibly basic set on Ebay. - Try and get one with a headphone jack connecting to the transmitter to save your self some hassle.
-If you are a motorcyclist you more then likely have a helmet already
(1)various tiny screwdrivers.
(2) soldering iron.
(3) pliers and snips.
(4) various workshop tools.
Step 2: Opening Up Your Sony Radio..
To open up the radio you need to remove the necessary screws, there's one on the back and one concealed within the battery compartment.
once these are out, flip the radio so the longest flat edge is facing you. wedge a screwdriver gently into the top join and pries open the radio.... Check out the short video for step by step details.
The transmitter I bought opened easily with only one screw holding the whole thing together!
Step 3: Identifying and Adjusting Components
Next step is to decide what sort of housing you would like to design for your radio. I wanted to keep mine very minimal and relatively small to reduce distraction to the user when traveling at speed.
By deciding what you want your radio to look like you can also decide on the layout of the controls. These need to be extended from the circuit board so deciding where you want them will help with the decision to extend them. One thing I will say is that I wouldn't recommend detaching the tuner as it seems to reduce the quality of the reception considerably. I chose to extend the On/Off/volume dial, speaker, battery pack and arial.
The on/off/volume dial rotates around a fixed point which is absent once the component is detached from the board. To counteract this problem I milled a very thin piece of wood to replicate the cavity in the circuit board.
Extending the components is reasonably easy;
De-solder the component's attachment to the board - (a solder sucker helps this process)
Cut the appropriate amount of wire depending on the part's desired distance from the board.
Solder the legs of the component back to their original destination on the circuit board.
Be careful not to apply heat for too long to the circuit board or you may overheat it.
If you are careful with the soldering all components should work exactly how they did when attached to the board.
For the transmitter all I did was extend/ replace poor quality wires and significantly shorten the jack wire.
Step 4: Fitting the Headset to the Helmet
Disassembling the headset is a wee bit fiddley, There are no screws holding the headphones together so opening them requires a bit of gentle persuasion! once opened you'll see that one side houses the batteries and a speaker, while the other houses all the circuitry and a speaker. The idea is to separate the side with the circuitry from it's respective speaker. This is done by simply elongating the wire which connects the speaker to the board and by striping back one wire strand from a multicore wire in order to distance the board from the speaker.
The reason behind this is that you want to separate the controls from the speaker and mount it on the outside of the helmet. leaving the speakers inside.
Next step is to either drill a tiny hole to feed the wires through or tape the wires up the outside and fix the controls around the jaw.
This can be done by means of a glue gun which will hold the controls firmly on the outside. or mounting the legs on screws.
Fitting the head set is a simple process. once you have the wires sorted with a reasonable distance between the two speakers just imbed them in the lining of the helmet and hide the wires. they are very thin and will not need much
Step 5: Building the Housing.
I begun Sketching potential housings for the radio and transmitter..
It quickly developed to the idea you see here. I decided on this design as I felt it best suited the curvature of the handlebar. I put all of the dials and switches on one face for easy of use when driving. I produced a number of cardboard prototypes to get exact measurements and work out any potential problems in design before building.
I made the wooden element in 3 parts; Base and two ends (similar to a bed!)
The ends were made by glueing two pieces together, while the base is made from one solid piece.
To make the ends: cut 6mm plywood into a rectangle of 110x90mm. from the base measure up 35mm and draw a line across, then another 25mm up and draw the arc for the top. Measure in 15mm from each side on the base and join with an arc. (see photo 2)
depending on the thickness of your perspex, cut another 6mm piece of plywood the same width as before - minus the width of the perspex. height 25mm + arc (this piece should sit on the 35mm line we drew on the previous piece). These need to be glued with wood glue and clamped for about an hour.
Once the glue is dry, one of these ends (on the inside) needs to be routed to create enough space to fit the width or your radio circuit board. Measure out the position of the dials and use a milling machine, jigsaw, coping saw or even files to make the slots. (see photo 4). once these are done its time for the base.
To make the base: Cut a piece of timber (any kind will do as it will be hidden from view) 104x150x35mm. create the base arc in the same way as before; measure in 1.5 form each side and draw the arc. To hollow out the arc i use a sanding machine available in the workshop but if you don not have this available to you I would chisel the majority out and sand it smooth. Drill two small pilot hole on each side of the base for later attaching of the cover.
Glue the ends to the base and clamp.
Step 6: Moulding the Shell..
To make the shell:
Make a mould by sanding down a 104x150x40m block to the same arc as your end pieces. Spending time on getting a good mould will be evident in the finish of the plastic. Cut the perspex slightly larger then what you need (perspex shrinks slightly when heated).
If you are using an oven (the undoubtedly easier option) you will need to heat it to 160 degrees and put the plastic in for about 5 minutes. Using gloves, remove the plastic, align at one side and gently smooth over the surface to form a tight fit. Clamp at the other side and allow to cool.
If you don't have access to an oven you can use a heat gun to bend the plastic. This will give the same result if you're careful but will take a lot longer. Starting at one side, clamp the perspex to it's wooden counterpart. Start by heating the edge and then bend while applying heat to get a nice curve over the top of the wooden mould. Be careful not to apply heat for two long in one place or you will end up an uneven bubbled surface.
Once your shell has hardened you will need to drill two holes either side to line up with the holes you drilled previously in the base. Use a countersinking drill bit to allow clearance for the screw head.
You will also need to drill a hole for the arial and measure on one side - 40mm in and 30mm up to make the slot for the transmitter's switch. NOTE: this should be done just before final assembly to guarantee accuracy**. I added a clear panel to show the transmitters LED.
Step 7: Logo (optional)
As part of the brief we were to come up with a marketable name for the product. I Played around with a number of ideas and decided to call mine 'zoom'. I sketched up a few ideas and finally settled on a logo i thought suited the theme of my radio. I decided that i was going to laser cut it into the curved perspex surface of the shell.
I drew up the idea in illustrator (files attached) and cut it out using the university laser cutter.
To finish i filled the engraved logo with white paint, wiped away the excess and allowed it to dry.
Step 8: Assembly and Testing..
At this point you should now have;
. A radio with isolated controls,
. A transmitter with jack lead,
. A helmet, fitted with receiver/headset.
. A wooden base and ends,
. A perspex shell,
. 2 battery packs.
To assemble these parts you first need to attach the radio chip to the base, you can do this by wedging it in place with a strip of plywood or by simply glueing it in place. The timber works better for future adjustments/repairs.
Next drill a hole in the timber partition to accomodate for the transmitters headphone jack.
Align the transmitter with the edge of the base so it is jutting out over the edge and screw down. Fit in the battery packs, and use a hot glue gun to fix in place.
Insert the arial into the hole you made in the shell and glue from the inside.
to finish, attach two hose clips to the underside and you are done!
To test: Turn on the transmitter and reciever and turn the radio dial on full. Press the reset button on the helmet and then the seek button. This will connect the helmet to the correct station. then use the radio tuning dial to find your favourite station!
I hope you enjoyed reading my instructable, Why not give it a go?!