My first Instructable takes the musical electronics from my Son's Toy Story birthday card and put it into an enclosure for him to keep listening to. He loved the tune it played so much but the card got destroyed so I wanted to preserve it for him. A bonus is that my 3 year old loves switches and buttons so it was a double whammy for him.
I'm no expert in electronics, just a little bit of experience with using a soldering iron and very basic audio electronics.
I am sure this could be replicated for other musical card circuits.
Step 1: Circuit From the Birthday Card
The circuit is quite basic, you press the metal contact, which completes the circuit, which causes the music to play. Two button batteries are powering the circuit - I have no idea how long the batteries are supposed to last. Given that a birthday card is by definition only for one day, then I'm not holding out much hope!
If they do run out then they can be replaced, the only gotcha is that they are quite enclosed so may be difficult to remove them without being destructive and require new enclosures.
Step 2: Materials and Tools
- 1 x Audio circuit from your favorite musical birthday card.
- 1 x Small project box, from Jaycar.
- 1 x Momentary Switch, SPST, from Jaycar.
- 1 x Standard Toggle Switch, SPST, from Jaycar.
- (Scrap) Cat5 network cable.
- Glue for heated glue gun.
- Rosin core solder, from Jaycar.
- Soldering Iron.
- Heated Glue Gun.
- Drill driver.
- Various HSS drill bits.
- 3rd Hand tool.
- Fan - to move away the dangerous fumes from the soldering.
- Stanley knife.
- Wire stripper.
Step 3: Safety (with a Sprinkle of Common Sense)
This Instructable requires the use of tools which can cause you harm,if you are unsure about how to use any of the tools and materials listed, then do not attempt this project.
You must use your common sense before attempting any Instructables, here are some tips:
- Eye Protection - protect your eyes, and anyone else close by from any nasties flying in the air from drilling or similar.
- Ventilation - make sure you solder in a well ventilated area as those fumes are bad for you. Ideally use a fan or similar to vent the fumes away from you.
- Sharp Objects - knifes and wire cutters/strippers are sharp, don't cut yourself or sever any limbs.
- Hot, Hot! - soldering irons and glue guns are extremely hot so be very careful, they will cause you pain and suffer terrible burns.
Safety of others is as important as your own. Think of those around you, take a leaf out of Riley's book and be sensible with safety. Remember, we want to win likes, not Darwin Awards!
Step 4: Prepare the Box
Chose button location:
To accommodate the switches you'll need to drill some holes for them to pop through. I went for side-by-side in the centre. You should be careful to check the box to make sure that the button body will not be obstructed and that there is enough size for the audio circuit to fit in. I used a small box and it all just about fit in there.
Drill pilot holes:
Take small drill bit size and drill a small pilot hole for each switch. The holes will be a guide for the larger holes you'll need to drill.
Drill the holes for the switches:
Try and size up the drill bit you'll need for each switch. I was not very organised here with my effort in that I didn't pay any attention to the actual size of the switch, so i just tried to size them up, see the pics. I don't have a huge range of drill sizes so i needed to get creative for the toggle switch due to its 12mm diameter. When drilling i was rotating the drill to create a larger diameter hole - I got there in the end.
Fit the switches:
At this stage I mounted the switches to the box to check there was a good fit and get a cosmetic preview of the final product.
Drill holes for the speaker location:
I was mounting the speaker so that it would face out of the base of the box so needed to drill the base plate, conveniently for me, it had a grid pattern with small dimples which made it easy for drilling.
The speaker was placed on the base plate centrally and the outline traced with pencil. Then I grabbed a small drill bit an drilled out some holes.
Now on to preparing the circuit itself....
Step 5: Modifying the Audio Circuit
First thing to do is review the circuit as it currently is. It still has the momentary switch connected and the speaker connected.
Detach the switch:
De-solder the momentary switch from the circuit, make sure you leave a clean contact for us to solder the new switches later on.
Detach and reattach the speaker:
Make a note of which way around the speaker wires connect to the board. Then go ahead and de-solder them, again, make sure you leave clean contacts. Solder the speaker back on to the board - you may think this is an unnecessary step, but, for me, I wanted to improve the quality of the solder joint.
Step 6: Switch Wiring
The next step is to create the switch wiring and to attach this to the circuit. The switches will be what Riley will use in order to play the audio from the box. The switches will be wired in series, meaning that the toggle switch will need to be in the On position in order for the momentary switch to be active. This wiring will connect between the two terminals where the temporary switch was preciously located.
Prepare some wires:
I prepared 4 wires each only a couple of inches long to create the switch wiring. I used the scrap Cat5 cables I had lying around. The ends were stripped and then tinned.
Tin the switch terminals:
Make sure you tin the terminals on the switches prior to connecting the cables - it'll ensure a good solder contact.
Connect the switch wires:
Solder a separate wire to each terminal and check that the joint is good. You should have two switches, each with two wires connected. I chose different colored wires to easily distinguish them apart.
Connect the switches to the terminals:
Solder one wire from the toggle switch to the first terminal and the momentary switch to the other terminal. There should be two wires not connected to anything. Solder these two wires together to complete the circuit.
Now you can test the circuit to see if it works! Mine does, check the video.
Step 7: Putting Everything in Place
The last stage is to bring everything together in the box and fix everything in place. We bring out the glue gun for this part.
Fix the switches in place:
Mount the switches in the box and ensure they are firmly fastened in place.
Glue the speaker in place:
Use the hot glue gun to fix the speaker in position. Do not worry if it's messy like mine, you wont see it.
Place the main circuit board:
The circuit board had to be placed in the box at an angle due to the bulk of the toggle switch body. I got lucky and was able to fit it in at an angle. I wanted to fix it in place as much as possible so i scored the inside of the box where the board would make contact, this so that the glue had a rough surface to adhere to. Then I placed the board in and dropped a big blob of glue making sure the glue was on the bottom of the board and in contact with the box.
Glue the bare connections:
To prevent any of the bare wire/terminals of any of the components, I decided to put some blobs of glue around the place to help insulate.
I'm not an audiophile by any stretch of the imagination, but, I did notice that the sound from the speaker was heavy and a bit tinny. To try and soften the sound I added some bits of foam into the box before I closed it up. The theory was to dampen the sound to make it sound less harsh. Also, packing it out with foam wil provide some shock absorption should Riley drop the box.
No need to glue in place, just cut and shove into place.
The final step is to fix the base plate to the box and screw together. The box should clip nicely into place and be firmed up once fully screwed in.
Now for the fun of testing!
Step 8: Conclusion
I gave the box to Riley and he loved it which was particularly satisfying for me as I'd reached the goal i had set out for. The foam did a real good job of making the sound much clearer and rich, so highly recommend you add some in there. I added a video of the final product.