By David Humphreys

Originally published in EUG #10


This program will read the conductivity of any object and then plot a graph showing this property as a percentage. What use is this, you may ask. To be honest, I've no idea, although it can be fun to hold a probe in each hand and compare notes with your family, etc. I'm sure it could be put to more serious use, but for now let's regard it as a toy!

What You Need

All that is needed is an Electron, Plus 1/AP1/Rombox/Rombox+ to begin with. Then you need a couple of 'probes' - two old forks would do (No, Will, not the plastic 'picnic' variety!) - on suitably long leads.

You will need a 15-pin D-type plug to fit the A/D (joystick) port. Solder one of the leads to pin-15 (Analogue channel 0) and one to pin-11 or pin-14 (Analogue Voltage reference, Vref 1.8v) depending on which you find easier - consult the Plus 1 User Guide if in doubt. Now simply connect the D-type plug to the Plus One and you're ready to go! Nothing could be easier!

The next thing to do is to connect the probes to whatever you want to measure. A good test item to start with would be yourself. Hold a probe in each hand. If you can type with both hands full you're OK. If not, put them down, run the program and grab them again. You will see that everything starts to happen after around ten seconds. Just leave the probes in place and a graph will be plotted of your conductivity. When the graph is finished, the program will calculate your average conductivity as a percentage. Just type Y to exit the program or any other key to begin again.

Suggestions For Use?

This is quite a lot of fun when finding out just how much of granny really is solid steel, but I am convinced that it can be used in a more useful way. If you have any suggestions, I would be pleased to hear them. Happy measuring!

David Humphreys, EUG #10