Third Hand for Your Multimeter
by russ_hensel in Circuits > Tools
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Third Hand for Your Multimeter
You often need more hands for jobs with your multimeter than the normal body is equipped with, if you are an insect or octopus, or do not use a meter much, then this instructable will be unneeded by you, if you are human and do much electronics work, I think it will help you out.
Tools and Materials
- Scraps of hardwood
- Bit of metal sheet ( copper or brass is particularly nice ) or piece of un-etched circuit board
- Set of binding posts
- 2 alligator clips
- Ribbon cable connector from an old computer
- Bits of wire
- Hot glue gun
- Saw and drill
- Soldering iron
Building the Base
I used 2 small pieces of oak for the main base and body of this gadget. None of the measurements are critical, plan it out yourself. Two holes are drilled for the binding posts, and 2 for the alligator clips. These are both in the upper part of the base, the lower part has 2 holes to get at the back side of the binding posts. Make some grooves to let the wires pass between the upper and lower part of the base,solder 2 wires ( I used red and green ) one to each of the binding posts, After assembly the two parts are glued ( or screwed might be better ) together.
Building the Mini ProtoBoard
The mini protoboard is simply the plug end from a computer ribbon cable. Pull the top off the cap of the ribbon cable connector. Underneath you will see two rows of pins sticking up. Using fine wire ( I used wire stripped from a Ethernet cable ) connect all the pins on one side together and all the pins on the other side together. Have some of the wire hang out to the side of the connector to connect to the rest of the circuit. { There are a couple of instructables using this technique to make bread boards or protoboards see: Diy breadboard from old IDE cables by 1001progetti https://www.instructables.com/id/Diy-breadboard-from-old-IDE-cables/ and Make your own breadboard by ratgod https://www.instructables.com/id/Make-your-own-breadboard/ }
Add Some Additional Parts & Wire It Up
Solder some wires to the alligator clips ( note in the photos where the wires are connected ). Then hot glue the the clips into the holes in the base. Take the bit of sheet metal and screw it to the base. One of the lugs is under one of these screws. Screw the second lug to the board. Hot glue the mini protoboard board to the base with the wire side down, the hole side up. The black binding post is negative. Using the lug on the sheet metal piece connect on alligator clip and one side of the mini protoboard as negative. The red binding post is positive. Using the second lug connect the other side of the binding post and the other side of the mini protoboard as positive. The binding posts, mini protoboard, and gator clips are all in parallel, the sheet metal is connected to ground. Refer to the pictures.
Use It
The whole point here is that you can connect the meter to your component with no hands ( of your own ). There are different connectors for different approaches, the pictures illustrate this.
- Plug the component into the mini protoboard ( particularly good for components used on protoboards ).
- Grab one or more leads with the alligator clip ( particularly good for components with “fat” leads ).
- Press a component up against the metal sheet, use you hand for the other end of the component ( particularly good for batteries ). For batteries you can add a dummy load - a resistor in the mini protoboard, 150 ohms is about a 10 ma load for a 1.5 volt battery.
Enjoy.