Introduction: PureTone: Hacking a Radio for an Enviromentaly Aware Student
The main property of the pure tone radio is to be as sustainable as possible. The reason for the large body size is to allow a low powered speaker to be amplified without extra electrical power. The body acts as an acoustical amplifier and because of this the sound is amplified to great effect.
Another key factor to this design is the hand powered dynamo that is used to charge the battery within the device. This feature works much like the one that can be found in wind up torches. The components and materials used to design and manufacture this device will be recycled and mainly sourced from a sustainable
Step 1: Manufacture Overview
4 x Small Hand Clamps
1 x Small Panel Pin Hammer
1 x Chisel
1 x Roll of Duct Tape
1 x Bottle of PVC Glue
1 x Hand Drill
1 x Coping saw
1 x Epoxy Resin
1 x Epoxy Hardener
Selection of Wood Files
Selection of Drill Bits
80 grade Sandpaper
230 grade Sandpaper
Access to a Pillar Drill
Access to a Ban Saw
Access to an Industrial Sander
Access to a Hand Sander
200 x 300 x 5mm Pine Plywood x 2
750 x 180 x 1.5mm Pine Plywood x 1
600 x 30 x 20mm Pine x 1
110 x 90 x 5mm Pine Plywood x 1
*Plus Other Sourced Components
Step 2: Electronics
First of all you have to get an already functioning radio. Once you have bought a radio that will suit you must deconstruct it, (all we want is the circuit).now we have the radio circuit out we can start to desolder all the components that we want to remove or expend in length. In the image you can see here, the circuit is sitting in the middle and there are lots of wires coming off of it. My circuit came all compact and not at all messy.
The first thing you need to do is desolder all the components such as the ON/OFF switch and AM/FM switch, other things you may want to remove are things like the Volume and tuning dials. Once all of these things have been removed you can solder wire into the place that the components were. Once that is done reattach the disordered components to the wire that are now in their place. Once that is done all the major components that we need to extend will be extended. The components need to be extended so that they can reach the side of the radio casing allowing interaction.
Once that is done we can move on to removing the speaker. Once the speaker is desoldered you MUST bridge the circuit as the removal of the speaker will create a break in the circuit. Once the break is bridged you can bring in the Portable vibration speaker (I used a "ROCK-IT Portable Vibration Speaker System" in my radio.) most speaker systems can be picked up for around £14.00 online. Once you have purchased the speaker system just plug it into the headphone socket.
The next major change is with the power to the radio. Most radios will be powered via batteries. In tis radio it is powered using a hand powered dynamo. This is basically a motor that is attached to a handle and when the handle is turned the motor is turned backwards and creates an electrical charge. The charge is then collected by a small battery and is used to power the radio when it is on.
I picked up this dynamo my hacking an existing wind up torch but you could make one yourself if u wish. As you can see in the image of the circuitry the hand dynamo (top right) is attached to another circuit that controls the flow of the current into the battery and from the battery into the radio circuit itself.
Once you have completed that stage you can move onto the actual radio body and the real fun in this project.
Step 3: Body Shape Generation
First thing to do is to cut out the main body shape out of the 200 x 300 x 5mm ply. This is the shape I used in the image (you can change it as you feel appropriate) my shape is made to resemble an acoustic guitar. Once you have made the base shape draw around it to create an exact replica on the other ply of the same size. It is very important that these pieces are identical in shape to sand them until they are. It can help to attach them both together with the Duct tape and sand them together. This will make them identical.
Step 4: Base Cuts
All the cuts that need to be done to the base must be done now and so now is the time that the door to the electronics must be made. As the body need to be completely sealed and as securely as possible the only way to the electronics is thought he bottom via a removable panel. So draw out a shape that you wish to cut. My drawing can be seen on the image. Once you have drawn the shape simply cut it out. Using a drill to create a hole is the best start; once a hole has been made you can then use a coping saw to cut out the rest. Once this is done the cut will be rough so use the wood files to smooth it out. One you are happy with your place the hole over the 110 x 90 x 5mm plywood panel and mark out the shape. Once you have drawn that out you will have an estimate of the panel size that must be cut to fit into the base as the lid. Remember that the lid must fit very tightly so be very careful and only shape small parts at a time. Once you have fitted the panel perfectly you can move onto the next stage.
Step 5: Creating the Radio Frame
The next stage is to create the radios height. We want the radio to be 140mm in height so use the 600 x 30 x 20mm pine as a frame. Cut the pine into 4 parts measuring 130 x 30 x 20 each. Combined with the thickness of the bottom and top panels this will make the radio 140mm tall. Place these 4 components as shown in the image; make sure that they overlap the sides. the reason that the components must extrude past the edge of the top and bottom panels is because they must be flush with the side (this will make one of the final stages possible. the 4 components must be glued (not screwed) to the two panels using PVC glue. once that is done clamp them using the 4 Hand clamps.
Once the glue is dry (about 15mins) Remove the clamps and sand the 4 components flush to the sides of the panels. Once that is done move onto the next stage
Step 6: Creating the Component Housing
The next part of the development is to create the housings necessary to attach some of the electrical components to the radio body. The only tricky one is the hand dynamo. a small housing must be made out of wood to hold it together and then there must be a small hole made to fit it into (both of these can be seen in the images). This component must fit flush with the radio body with no gaps so a steady hand and expert eye is needed for a good finish.
Step 7: Attaching the Side to the Body
This step is a very important one that can go wrong very easily so it is a good idea to get a hand (although it can be done by you alone). Take the 750 x 180 x 1.5mm play and glue it to one of the side pillars. Leave it to dry for about 15 minutes and then apply glue to the edges of the panel around about a quarter. Take the duct tape and tape the plywood to the body of the radio as tightly as possible. Once you have taped to the first quarter stop and wait 15 minutes to dry. Repeat this method all the way around the body.
There should be a little overlap at the end of the ply as 750mm is just a little bit longer than necessary. Cut this excess off with a Stanley knife or chisel. Once that is done and you have left the body to dry for about 1hr remove the duct tape and sand away the excess ply that protruding over the top and bottom on the radio. Sand until the ply is flush with the top and bottom panels.
Once that stage is complete you will notice that there is a rather unattractive line where the ply has been attached. Take a slice of hardwood such as mahogany or oak and place it over the line to hide it. Do this on both side and your design will look so much more sleek and finished.
Step 8: Applying Final Finishes
Now that the body is all together you can start to sand it to a smooth state. Once all the sanding is done and the body is a smooth as you want it you can apply a finisher, I decided that Danish oil would be the best idea and so I applied 3 coats of that. A good idea is to sand the finish down between coats with a fine steel wool.
Step 9: Creating the Switches and Other Components
I had to create some of the components either due to the fact that the original ones couldn’t be changed and needed to be developed to fit my purpose or because the originals were not appropriate. For example the original volume switch was a disc mechanism and I fitted a potentiometer instead, this was so I could attach a knob.
The original turning switch was also a disc mechanism but nit could ne be changed so I built an attachment onto the mechanism to act like a makeshift potentiometer. I then attached the tuning base to the inside of the radio body to secure it.
Step 10: Attaching Electronics and Switches
Once all the finishes have been applied to the body you can start to cut the holes for the switched to fit through. Mine has a hole for the AM/FM Switch, ON/OFF Switch, Tuning Knob and Volume Knob.
When you have finished that you can move on to actually fitting the electronics. Once the electronics are in you can start putting the switches thorough the holes. I just used the AM/FM switch and tuner from the original radio but I changed the on/off switch and the volume.
You can buy these other components from an electronic store, I personally made the knobs myself out of teak but you can buy them from an electronic store also. When this step is finished you are on to the final stages of the design.
Step 11: Finishing Up!
Once all the electronics are in you can give the radio a final finish with Danish oil or equivalent. Once that has dried you can take a step back and look at what you have created.