No, not that kind of trick, you pervert*.
I was doing some homemade wiring, and whether it’s power or signal, you generally want to use twisted-pair (or triplet, or quad, etc.). It’s faster than running all of the single-wire, so there’s a labor-saving aspect to it, but there’s a data quality aspect to it as well.
Any time you have a pair of wires that completes a circuit, you have to worry about ground loops and other signal pickup. If the wires are separated, and the magnetic field that runs through them changes, Faraday’s law tells you that you’ll add some current or a potential difference to the loop. The bigger the loop, the more flux you’ll be capturing. If you write this onto the common ground for your experiment, you will be putting this signal onto all of your equipment. And this is not just the earth’s field — everything radiates. A loop is an antenna for picking up 50 or 60 Hz power and also any other frequency equipment you use in the lab. (Early on in my current job, in the dark days before I had a CD-burner, much less an iPod, I tried listening to the radio in the lab. At one point we added an Acousto-optic modulator and started driving it a smidge above 100 MHz, which was almost the same frequency as the local oldies station, and I couldn’t get that station anymore because of the interference). This will get written on to your signal lines, and will get picked up by power lines, which then writes it on to all of that precision equipment you soldered together, and forgot to add bypass capacitors everyplace you needed them) . Chasing down ground loops is a big pain, as is filtering out noise. Twisting the wires means that the net current flow of any power signal is zero, as current input is as close as it can be to the return path, so the far-field radiation — basically anything further away than the diameter of the wire bundle — is nonexistent. If it’s a data line, it doesn’t look like an antenna, except perhaps for extremely high frequencies — the area for magnetic flux is vanishingly small, so it has no opportunity to pick up a signal.
So you want twisted-pair, but the commercial pickings can be slim for the exact wire type you might want to use, and besides, you want to color-code what you’re doing. So here’s the trick: use a drill. Clamp on to the wires with the chuck, pull taught and squeeze the trigger. Wind up to a reasonable pitch and — I cannot emphasize this enough — release the chuck before lessening the linear tension on the wires. You’ve added a lot of “twist” to the wires, and they will untwist. If you release the linear tension first —trust me on this — it will jumble up like a telephone cord. (If you’re under 30 and don’t understand the phrase “telephone cord,” it’s the phone you’ve seen at your grandparents’ house, perhaps in the basement. The phone might even have a round disc on the front, with ten holes in it around the perimeter)
*my conclusion after perusing the somewhat disquieting search-engine stats. Suffice to say that using “animal robo-p*rn” in a title isn’t leading to searches that are attracting science-minded folk to the post.
