Auto Tuning off Oct 27-28, 2005
The autotuning, or dither, in the Sigma Tau maser
produces sidebands at +/-28 Hz,
which can be a problem for some observers.
During a Lunar radar run Oct 26-27, 2005, the
autotuning was turned off.
This resulted in the frequency changing by
ΔT/T = 3.22x10^-11.
The offset of the site 1 pps vs GPS is plotted
here. The samples are every two minutes.
- A Dithering is turned off at 11:00 UT on Oct 27. Offset=-1180ns
- B Dithering is back on at 14:30 on Oct 28. Offset=-4360ns
- C At 17:00 UT 1pps offset is adjusted to near zero. Offset=+120ns
From "A" to "B", the clock offset runs from about -1200 to -4300 ns.
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