[evlatests] X-band subband ordering

[Bryan Butler]

i agree.  with v2, and all the OPT, VCI, CM, etc., changes i think we 
should wait until that dust settles before doing anything serious on 
this.  there are other tests that can be done of course...

	-bryan


Michael Rupen wrote, On 2/20/10 08:44:
> There is clearly something wrong with the X-band labelling.  I would
> prefer to defer further & deeper tests until we've switched completely
> to the new "automated" approach to getting metadata through to the SDM,
> next week.  There are many tests to do but we will just have to re-do
> them when the new system is in place giving (for instance) both baseband
> pairs at the same time.
> 
> On the VCI side there are many possible confusions.  Note for instance that
> we auto-magically change the filter sideband flippers so that the CBE
> *always* receives USB data, at every band.  We confirmed yesterday that
> this does indeed work.  There is a great deal of development going on at
> the moment with the VCI and the Configuration Mapper.  Again it would
> seem wise to let the dust settle before checking the details of such
> messages.
> 
>                      Michael
> 
>> Looking at some VCI documents with Adam earlier today we were surprised to
>> see LSB used for all bands where I would have thought X-band to need the
>> opposite sideband sense...
>>
>> -W
>>
>> On Fri, 19 Feb 2010, Rick Perley wrote:
>>
>>>    A quick perusal of X-band data shows that the ordering of the
>>> subbands is reversed:
>>>
>>>    The correct spectral features (and continuity of phase) are
>>> recovered if the subbands are ordered {4,3,2,1}, rather than their
>>> current ordering {1,2,3,4}.  Note that this is not the same as simply
>>> reversing the frequency axis.  It appears the frequency ordering within
>>> each subband is correct (and runs 'backward').
>>>
>>>    Data quality looks good, but a closer inspection is needed.
>>> _______________________________________________
>>> evlatests mailing list
>>> evlatests at listmgr.cv.nrao.edu
>>> http://listmgr.cv.nrao.edu/mailman/listinfo/evlatests
>>>
>> _______________________________________________
>> evlatests mailing list
>> evlatests at listmgr.cv.nrao.edu
>> http://listmgr.cv.nrao.edu/mailman/listinfo/evlatests
>>
> _______________________________________________
> evlatests mailing list
> evlatests at listmgr.cv.nrao.edu
> http://listmgr.cv.nrao.edu/mailman/listinfo/evlatests