Tom Van Baak wrote: > measure to 1 ppm within ten seconds. > > /tvb > http://www.LeapSecond.com > > p.s. For extra credit, tee your UUT into both channels, do twice > the math, and see if you can measure both differential phase, > and differential phase drift between them. > > > Tom
A better way may be to drive both sound card input channels in phase quadrature with a pair of sinewave signals. One can then any variations in calculated phase (arctan (L/R)) will be due to differences phase variations between the L and R channels and variations in the phase shift between the 2 signals. Since 250us of delay line is somewhat inconvenient, will have high attenuation and will be very expensive some other means of generating the 2 signals in phase quadrature is required. Corrections would need to be made for the effect of amplitude and quadrature phase errors. Bruce _______________________________________________ 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.
