Introduction: How to Fix Your Missing Multimeter Battery Pack and Cable Testers

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

Picture of Materials

two-sided tape
duck tape
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
shrinking sleeve

Step 2: Disassembling the Multimeter and Getting Some Parts From Broken Toys

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of 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

Picture of Building the Testing Side on the Testing Wire
Now for the other side of the testing wires. I used a large paper clip, straightened it out and folded it in half. Then I cut it in half. I took one of the halves and connected the black wire to it with a bit of duck tape and a bit of the exposed wire by wrapping the wire around the half piece of the straightened paper clip. Then I soldered them together. Finally I wrapped 3/4 of the metal part and wire with duck tape and covered all that with a shrinking sleeve to make it super sturdy.

I repeated all of these steps for the red wire as well.


This completes the build. Hope you have enjoyed my tutorial.

Comments

pfred2 (author)2012-03-17

Nice you got that meter working again. I'm curious how you knew what kind of batteries to put into it? By the looks of it I'd have guessed someone chopped out a 9 volt clip, if there were no other clues. With the Internet today I'd download the manual for it off the manufacturer's website. I always try to do that with stuff I get, that I don't get new. Hint, hint.

For probe leads go with clamps of some sort. If you need to probe you can always stick a little piece of wire into an alligator, or hook clip. Clamping straight probes to anything is hard. I find right angle probing a bit more comfortable anyways.

I think the only reason they make straight probes is well, because they're cheap. They have to throw you something when you buy a meter. Unless I'm checking something like a wall outlet I hardly ever use straight probes though. They're kind of clumsy.

Some of the meters I've picked up over the years:

http://i.imgur.com/8dalX.jpg

It is safe to say I've something of a meter fetish. I've more, I just didn't feel like digging those up for the group shot. You know, the deep storage stock. That is just my surface meters I have kicking around.

benji.abrams (author)pfred22012-03-20

Well the batteries I basically went with my instincts and use whatever I had laying around at home, But thank you for your great tip,
For the alligators and tester probes.

this is my solution : I took 2 alligator clips and 2 short pieces of wire red and black,shrinking sleeve and another 2 pieces of metal from a PC power supply power connection(which actually fits perfect with the probes).

soldered it all together and put the shrinking sleeve on the edge with the metal piece to insulate. that's it you have extensions with alligator clips 

PC power connection
Multimeter and extensions

pfred2 (author)benji.abrams2012-03-20

When I make clip leads I hook the wire right up to the clips. I find the addition of probe handles a bit cumbersome? I've commercial clips that attach somewhat like yours do but they fall off a lot. What you've made is different though, with the little whip lead wire, so maybe it'll work out better for you?

Your idea is very inventive though. Gives me an idea to use those PC power connectors as mini jacks in other projects.

benji.abrams (author)pfred22012-03-20

The idea of using the connection came to me from my other projects which I used the PC power connections as mini jacks.
By the way my connections never fall off they fit like a really tight glove.

I'd like to see how you use the PC power connections in your projects

pfred2 (author)benji.abrams2012-03-20

The last time I went into a Radio Shack and asked the kid working there if they had any banana jacks he looked at me like I was bananas. They did, I found them myself, but it got me thinking maybe I'd better find new sources for supplies.

The last electronics project I worked on was an ESR meter, I haven't gotten it to work yet, but when I do and box it up it might be nice to use some jacks with it.

I have a couple nice meter movements here and I need to do something with them. Whatever that ends up being I think there might be jacks involved.

benji.abrams (author)2012-03-20

P.s.
Really cool collection