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Domain: lge.com

Stories and comments across the archive that link to lge.com.

Comments · 51

  1. Re: PCI 802.11b cards by Raetsel · · Score: 3, Informative · on Intel's 2.4GHz Pentium 4 Unleashed

    First, I never said the pins were carrying 2.4 GHz signals. I said they were "waveguide-like". They will likely facilitate the radiation of some of the ~75 watts dissipated inside the chip package. Simple physics: energy goes from source to sink -- there is less similar radiation outside the package, thus there will be leakage. Fact of life. Need to reduce / prevent interference? That's what the grounded metal case is for.

    Second, at 2.4 GHz a signal doesn't follow a wire (or a circuit board trace) like it does at 60 Hz. At 2.4 GHz a wire is more of a 'suggestion' than a 'command'. This is why (radar | microwave ovens | certain satellite communication systems) use waveguides instead of wires. It's also one of the reasons everything isn't running at the same clock speed.

    Third, one of the Ten Commandments of /. -- Thou shalt query Google.

    None of these are PCMCIA > PCI adapters, though some of them look like they're using the same innards. I'm not even going to include all the 'Mini-PCI' cards being used in laptops these days. Yes, they all have some shielding. No, it's not as complete as a PCMCIA card -- if I even dare call that complete.

    PCI Cards are installed with the PCB facing in the general direction of the processor (in the ATX spec). I don't know the shielding capabilities of circuit board material, but it sure isn't a solid conductor -- and... many of your traces are exposed to the radiation inside the case. This is where I expect problems and performance degradation to have their roots.

    Perhaps you remember a few years ago when it was trendy to install shielding around your audio card for a greater Signal/Noise Ratio? I saw people use copper flashing (the stuff you use to keep your roof from leaking) to construct a box, doing a very nice soldering job, use stand-offs for installation... all to remove a little static. The whole trick was to construct a Faraday cage that would allow the ISA connector (remember those?) as little clearance as possible, without actually shorting it.

    We may see a resurgence of that technique.