We used an Rb magnetometer to measure total charge change due to lightning in 1964 or thereabout- Don Latham
Tom Van Baak > Although we time-nuts prize quartz oscillators that are highly-stable > and well-insulated from environmental effects there is an entire > industry doing the exact opposite -- using quartz as a sensor. > > Some of the best thermometers are based on quartz oscillators > (hp 2804A) cut to maximize, rather than minimize, their tempco. > > And billions of accelerometers (from air bag sensors to Wii game > controllers to the iPod touch and iPhone) have been produced in > the past decade. Google words like MEMS Quartz Accelerometer. > Also for Quartz Rate Sensor QRS. > > I've seen quartz resonators used to measure to impurities in the > making of semiconductor wafers -- they measure the change in > frequency of an exposed quartz resonator as atoms fall on the > exposed crystal and change its frequency. Note that a 1 mm > quartz crystal is only about a million molecules thick. So adding > a layer of only 1 atom will change the frequency in the ppm range. > We can measure a thousand or million times better than that. > > As you feel your heart beat, google for Quartz Pressure Sensor > > Quartz is really quite amazing. It's almost a shame to shield it > from everything so all they have left to do is try to measure time! > > One other note: rubidium vapor frequency standards are much > more sensitive to magnetic fields than cesium beam standards. > I've heard that military sub-hunting sea planes use deliberately > un-shielded rubidium clocks to detect hidden submarines. Google > for words like Rubidium Magnetometer ASW P-3 Zeeman > > As always, one man's error is another man's signal... > > /tvb > http://www.LeapSecond.com > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
