CDR: RE: Burglar Politics, Tempesting PC's that watch TV and DVD regio
---------- Lucky Green[SMTP:shamrock@cypherpunks.to] wrote: Sunder wrote, quoting
http://www.theregister.co.uk/content/1/13863.html
<SNIP> [...] It's my understanding that TV detector vans work by picking up the radiation emitted by cathode ray tube TVs - which should mean that, if you're rich enough to run an LCD monitor they'll never know you're a secret Paxman admirer.
A popular, but false, myth. The video cards radiate more than the CRT's. Laptops tend to be the worst offenders.
--Lucky Green <shamrock@cypherpunks.to>
Yep. Most laptops have a video card for attaching an external monitor, with an unshielded port - they thus spray out monitor-driving RF signals while they run, regardless of whether there is a monitor out there to receive them. Of course, a *good* laptop design would power off the video card if it's not in use, to extend battery life if nothing else. I don't know if they do this. One of my home systems is a Compaq desktop with an LCD screen. It does *not* use a standard video cable: there is a pure digital interface for the LCD. (I've never investigated as to whether I can seperately remove the SVGA card or interface). Peter Trei
On Thu, Oct 12, 2000 at 10:12:42AM -0400, Trei, Peter wrote:
Yep. Most laptops have a video card for attaching an external monitor, with an unshielded port - they thus spray out monitor-driving RF signals while they run, regardless of whether there is a monitor out there to receive them.
Of course, a *good* laptop design would power off the video card if it's not in use, to extend battery life if nothing else. I don't know if they do this.
All the laptops I've used in the last 6 years (IBM, Compaq, Dell) have had built-in hotkeys to switch from LCD, LCD+CRT, CRT. Monitors attached to the VGA port while the laptops were in LCD-only mode consistently blinked their messages for "No video source". APM (which virtually all current PCs support) allows for monitor blanking, suspend, and powerdown. XFree86 and Windows support these functions. -dsr-
"Trei, Peter" wrote:
Of course, a *good* laptop design would power off the video card if it's not in use, to extend battery life if nothing else. I don't know if they do this.
they do. my thinkpad has a config option where you can turn the external display on and off.
participants (3)
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-dsr-
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Tom Vogt
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Trei, Peter