Thread: IDE cables
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Old 20th March, 2002, 04:18 AM
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Wa11y Wa11y is offline
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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.
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