Tom Walker wrote in a message to Jean Parrot:

->         I had an alternator controler on the sloop and it showed a
->         digital meter for Amps and Volts. When turning the Thinkpad on
->         using the 12v rig, the ampmeter in two decimal, showed barely a
->         change. I wish that I had kept some figure but my use of the TP
->         was not restricted at all until I turned the 2m on TX. It
->         pulled, the 2m, quite a bit of juice when TXing at 25 W.

 TW>  Laptops are pretty power efficent Computers. They typicaly draw .5
 TW> to .75 amps. And of that the Screen Back light draws about half of
 TW> that. The big prolbems in that people want them as small and as
 TW> Light as possable so they build them with small batteries. People
 TW> Gripe about the 2 to 4 hour usage with those batteries yet would
 TW> scream Lowder if they had a Bigger(Heaver) battery.

Not me!  I surely wouldn't mind a few extra pounds if I could have it
increase the runtime to something nontrivial.  But the market doesn't seem
to be offering me that option lately.

 TW>  It is a Loose/Loose situation for the manfacturer.

Lose/Lose?  :-)

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