The other day while I was visiting a friend, I showed him some purchases I made on eBay. Realizing that I had purchased something that he had just laying around the house, something he claimed he didn't need anymore, he offered to give it to me. The item was his old multimeter. He gave it to me thinking that it was missing its batteries and didn't have its testing cables.
When I got home, I started checking it out and trying to add batteries to it. It was then that I realized that it not only was missing the batteries but also the battery pack. All that was left were two cut wires; so I found a few broken down electronics items that I could use to fix this multimeter device and restored it to working order. The following is a detailed explanation of how I did it.
Step 1: Materials
thin piece of sponge
small piece of foamed plastic
broken remote control from a toy for the battery connections
some wires from an old PC power supply
a wall wart
soldering iron and soldering wire
Step 2: Disassembling the Multimeter and Getting Some Parts From Broken Toys
Opening the multimeter : My multimeter has two screws in the back of it and two clips on the top of the back piece.
Toy remote control : This has metal springs and plates where the batteries sit which I used for my project. I used a screwdriver to free the metal plates and spring with a little bit of force.
Step 3: Starting the Build on the Missing Battery Part
Once I had opened up the multimeter and got the parts from my toy remote, I started the 'build'.
I took part 1 and put it on the two-sided tape and cut it off, creating a type of a sticker out of part 1 so it would be easy to connect to my project. Then I stuck it in place.
Next I took part 2 (which is actually two parts) and soldered a piece of wire to each one of them. Then I insulated the back metal plating on the part with the spring. I also placed the two parts on the two-sided tape and stuck them in place inside the multimeter.
After getting it all set up correctly, I started soldering the wires together and insulating them with a shrinking sleeve.
Step 4: Finishing Touches on the Battery Pack
Okay. Now that the electrical part of it was set up, I began finishing the battery pack so the batteries wouldn't move while using the multimeter.
I took the black spongelike material and cut a piece out to stick onto the inner back of the multimeter case with the two-sided tape exactly above the batteries.
The blue battery divider is the foamed plastic which I glued with the two-sided tape to the inside of the multimeter exactly between the two batteries... just like in the pictures.
Step 5: Building the Testing Cables From Scrap
Okay. Now that our multimeter will turn on and actually work, let's get started building the testing wires.
I found an old mosquito repellent gadget laying around at home and decided to use the part that connects
to the wall socket as my way of connecting to the multimeter for this build (you can use anything else that
will fit into the mutimeter for this part). I took the gadget apart. There were two screws outside and one screw
inside. Once I got the part I needed free, I could then start my project.
Step 6: Building the Testing Wire Connection to the Multimeter
Now that I've got my parts for the testing wires, I will take two wires from my scrap PC power supply,
red and black. (Because they were too short, I ended up extending these with two other wires, red and black).
I soldered the wires to the two parts from the last step and covered the wires with a few layers shrinking sleeves. Then I covered the part and the wire to hold them together with another shrinking sleeve. (You don't have to use a shrinking sleeve. You can use electrical tape; but it's not as sturdy).
Step 7: Building the Testing Side on the Testing Wire
I repeated all of these steps for the red wire as well.