In message <013401cf7c46$31ac3cc0$9504b640$@miles.io>, "John Miles" writes:
>(Some >people have even reported similar behavior with cesium standards, although I >don't see how that could happen. There aren't supposed to be any >first-order temperature effects in a CBT, and I'd think that any lower-order >effects would be way beneath the tube's flicker floor...) One important trick in this area: Always locate your DUTs physically orthogonal to each other. Almost none of our DUTs have 3 axis of symmetry, and therefore most environmental effects are not symmetric with respect to orientation. I noticed this by accident comparing three "identical" OCXO's because I had put one of them in a different orientation than the other two: The environmental noise were much larger between that one and the two other, than between the two co-aligned DUTs. I'm not entirely sure this is relevant for Rb/Cs/H, their environmentals should be attenuated enough for it to not matter. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ 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.
