[evlatests] Preliminary Wobble Report

[Brent Carlson]

Ken,

>
>> There's also the question as to whether the correlator chip integration
>> time, for this test, was set to some odd ball number, or the standard
>> 200 or 250 usec.
>
> 250 usec was used.  Bob believes that that would be less
> important than the choice of LO offset and wanted to test
> that hypothesis.  We should have also taken some data
> with both the improved Lo offset algorithm and an odd
> CC dump interval, but neglected to do so.

This effect can be quite large, as it limits anti-aliasing to ~-25 dB 
(~1%).  As the natural fringe rate changes, it can beat with this dump 
interval and cause oscillations on some baselines.  I'd say no further 
searching for causes be done until the complete algorithm is in place.

Brent

-- 
Brent R. Carlson
Brent.Carlson at nrc-cnrc.gc.ca
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