G'day, Having been enthused by linux.conf.au, my wife and I set up some more rural range tests of the B-Test-1 units.
- 2007-01-22 A, test from a high point on terrain, failed probably due to terrain obstruction or very high temperature, - 2007-01-22 B, repeat test using 1.3km known-good path, to exclude specific units from failure of 2007-01-22 A, worked fine, extended to 1.4km, - 2007-01-23 A, repeat test using 1.3km known-good path, during midday sun, to exclude solar coverage from failure of 2007-01-22 A, - 2007-01-23 B, test unit in full sun for an hour, monitoring signal and noise level, to exclude battery charge level and temperature from failure of 2007-01-22 A, logged ticket 800. We've restored use of a fantastic diagnostic tool ... an ordinary AM broadcast radio tuned to one of the emission frequency harmonics of the laptop. With experience, one can learn what the laptop is doing as a result of coverage changes. It can also be placed near the antennae to hear the transmission pulses. Sort of like an electronic stethoscope. Detailed test reports: http://quozl.linux.org.au/olpc/2007-01-22-A-radio-range-test.txt http://quozl.linux.org.au/olpc/2007-01-22-B-radio-range-test.txt http://quozl.linux.org.au/olpc/2007-01-23-radio-range-test.txt Photographs: http://quozl.linux.org.au/olpc/2007-01-24/images.html Graph of signal and noise over temperature: http://dev.laptop.org/ticket/800 http://dev.laptop.org/attachment/ticket/800/quozl-2-in-the-sun.png -- James Cameron mailto:[EMAIL PROTECTED] http://quozl.netrek.org/ _______________________________________________ Devel mailing list [email protected] http://mailman.laptop.org/mailman/listinfo/devel
