# Walking Calculator

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This may not work with all calculators.
Here is an interesting way to count footsteps and estimate how far you have walked.You need a cheap calculator, some foam or sponge, glue, foil, cellophane tape, and 2 long wires.

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## Step 1: The Switch.

Then you will want to make a switch. To do that, drill or punch a hole in the sponge for the to the bottom. Glue the foil to the top and bottom of the sponge. The two foil pieces should not be touching. Connect the wires separately to each foiled surface.

## Step 2: Mod the Calculator.

Open up the calculator and connect each of the other wire ends to the top and bottom contacts of the "equals" aka = button. Put a piece of cellophane tape between the contract so that they do not connect. Close the calculator and make sure everything works normally. you would have to press the switch together for the = sign to work. Attach the switch to the bottom of the shoe.

## Step 3: Do It to It.

Now enter "1 + 1" into the calculator. Start waking and you will see the count begin to rise as you walk. When you are finished walking multiply the steps to the length of your stride and you will have your distanced walked.

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## 4 Discussions

Nice 'able.

I'm going to throw out a couple ideas off the top of my hat holder. \$0.02 not included.

Suggestion0: Measure off a known distance, e.g. 50ft, 100m, w8vr. Walk the distance two or three times, counting your steps each time your left foot (ex-mil, hate marching, learned anyway) hits the ground. Add up the total distance, divide it by the total number of steps. Bingo instant average pace length.

Suggestion1: when you calculate your pace length, convert it to miles, km, parsecs, light years, w8vr, and put that into the calculator. Then you can read irt your walking instance directly from the display.

Suggestion2: Some keypads have both halves of the switch etched directly on the circuit board. In that case, both wires can come from either side of the '=' button, or you can use a DMM to trace the contacts out to the edge of the board. It may be less risky to solder wires to a remote location rather than directly on the delicate switch contacts.

Suggestion3: Use 3/16" shrink tubing to keep the wires neat between the shoe and the calculator. Use a heatgun, hair dryer, or butane lighter to activate the shrink tubing.

Suggestion4: You can scavenge a door interlock switch from a broken microwave oven, or you can buy a single limit switch from mail order company such as digikey for < \$1 (plus shipping) and hot glue or duck tape it to the outside of the heel of a shoe. The dedicated switch, perhaps with a few easy mods, should work better than a foil-sponge-foil switch as a long term solution. Hot glue is useful as decent weatherproofing / ruggedizing agent, if applied aggressively.

TL;DR multiply your pants' inseem length by two and convert to miles. Bingo, approximate average pace length.