Bill, I did a two sets of measurements using different methods. In the first, I watched the two waveforms in dual trace mode. The Trimble was on channel 1 (stationary) and the LPRO was on channel 2 (slowly drifting to the left). I started timing when they were phase (Channel 1 and Channel 2 occupied the same trace), watched the LPRO waveform drift through 180 degrees out of phase and then continue until the waveforms were back in phase, at which time, I stopped the clock.
In XY mode, I started timing from a right slanting diagonal (in phase), watched the form become a circle (90 degrees), saw it collapse to a left slanting diagonal (180 degrees out of phase), expand to a circle (270 degrees out) again and finally back to a right slanting diagonal (in phase), at which point I stopped the clock. The progression looked like this: /O\O/ So, my answer to your question is yes and no. Yes, I only counted the time until it returned to the same position. No, I didn't ignore the 180 degree state. Tom VB, Thanks for your calculation (100 / nS / 182 S = 5.5e-10): it feels more descriptive than the method I used. Joe, in the first experiment above, I used your suggestion (triggering on channel 1 and watching channel 2 slide to the right.) I have to think about what the drift direction means (your answer has an intuitive ring to it - moving right because the wavelength of the lower frequency is longer?) Thanks all for all of the replies. I'm afraid I've got the bug... (I found myself looking at a cesium clock on the web this afternoon.) Mark Silly question but I thought I would ask just the same. By in phase to in phase, and to make it clear, you did mean IF you selected the slant figure that went from bottom left to upper right, as the start point, that you only counted the time until it returned to the same position ? In otherwords you ignored the slant from upper left to lower right (the 180 degree position) while counting the rotation ? Bill....WB6BNQ _______________________________________________ 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.
