Hallo, C. Scott Ananian wrote: <snip>
> A last resort would be hooking up a MOSFET as a simple amplifier -- > again, you're not worried about linearity or any such niceties, but > you'd still need a good match for your MOSFET's threshold voltage... > some real measurements to replace the WAGes would go a long way. > --scott > measured on a B1 XO1 laptop (where the leds and the series resistor are wired in parallel it seam) : almost dark: 0mv ~3meter away from a 8w PL; bare led: ~2mv ~50 cm below ~25W halogen desk lamp; bare led: ~40mv bright white led directly on bare led ~200mv bright white led directly on light guide of the bat.led (lcd side) ~50mv ~50 cm below ~25w halogen desk lamp (~75* angle to the axis of the light guide) ~5mv i measure this between GND of the laptop the led side of the series resistor. all leds seam to be about the same.. i did not compare the different light guides. the main battery and DC power where removed, the RTC baterry was still in place. the meter i measured this with was fixed in the 2000mv range and was abou 10Mohm when i connected it to another meter in resistance mode; the (volt) meter read 250mv at that time. adding a 10Mohm resistor across the meter halved the ~50 cm below ~25W halogen desk lamp; bare led: ~40mv reading to ~20mv strangely enough when i add that resistor in series the meter said ~60mv so voltage on the leds must have been ~120mv? i will have to investigate this at a later time... if you want more measurement doen feel free to ask.. i also have a XO1 (production model ?C1?) that i could measure. i dont have a lux meter :-( Greetings, Reinder _______________________________________________ Devel mailing list [email protected] http://lists.laptop.org/listinfo/devel
