Quote:
Originally posted by Super
They're supposed to lower the EMI. |
Nope. Thicker insulation would be sufficent for that. Extra wires would actually cause more EMI due to attenuation. When you bundle a whole bunch of wires together, they bleed across. I see that sometimes when our customers try to neaten up their phone closet, and just bundle all the cables they can together and wrap them with a wire tie. Signal starts bleeding over, and T1s start getting slips and frame errors, you get crosstalk on telephones, all sorts of problem.
The reason that ATA/66+ uses 80 wires versus 40 wires that ATA/33 uses is for a transmit lead, and a recieve lead. Very similar to how DDR memory can now transmit on the top of the clock cycle and recieve on the bottom, ATA/66+ has seperate transmit and recieve leads, so there's less colision, allowing for faster access times.