Re: McDonnel Douglas warns against carry-on electronic devices

From:         caf@omen.UUCP (Chuck Forsberg WA7KGX)
Organization: Omen Technology INC, Portland Rain Forest
Date:         01 Feb 93 14:28:51 PST
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>Wiring that runs through the cabin area is not shielded, except for coaxial
>cables running to antennas.  Shielding is heavy and is avoided if at all
>possible.  If the passenger with the CD player is sitting next to the wire
>bundle, perhaps with his player leaning against the sidewall liner, it is
>very possible that either the digital or the analog signals from the player
>(which is not shielded either) could alter the data moving along the
>airplane's wiring.

Better start filling out the crash report forms.  My Sony portable CD
player puts out quite a bit of RF, completely swamping local stations on
the standard broadcast band on a radio held next to it.  This radiation is
comparable to a cellular phone on standby.

My laptop computer is much more powerful, putting out about the same
intensity of RFI at one foot.  It has extensive shielding and runs its 8
bit 8088 at 4.77 MHz; a contemporary 32 bit 25 MHz machine has more
electrical activity.

If a CD player can set a plane on its side, just imagine what serious RFI
would do.  If McD really believe a CD player caused this problem, they are
negligent in not issuing an immediate AD.

Chuck Forsberg WA7KGX          ...!tektronix!reed!omen!caf 
Author of YMODEM, ZMODEM, Professional-YAM, ZCOMM, and DSZ
  Omen Technology Inc    "The High Reliability Software"
17505-V NW Sauvie IS RD   Portland OR 97231   503-621-3406