In the special it looks like they used two HP5071A standards, an SRS620 counter, and a scope. They first made sure the stds were in sync then took one to the building at the top of the ski lift on New Hampshire's Mount Sunapee at 2726' elevation for 4 days where it would be running a little faster because it would be slightly further from the center of the spinning earth. After bringing the 5071A back from the top of the mountain they checked the difference in the start of square waves displayed on the scope and detected the 5071A at altitude was now 20ns ahead of the 5071A kept at sea level, as predicted, if I understood everything correctly. They explained that the clocks in the GPS satellites traveling at a much higher speed had to correct for the speed difference which also verified Einstein's theory.
My wife and I were on the top of Mt. Sunapee this summer where we enjoyed the views but didn't run any experiments. ;-) -Arthur _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.