[daip] The PC table problem has been understood

[Leonia Kogan]

Hi Enno,

I think I have understood the problem with PC table of your data.
I looked at the calibration file  (BM261CAL.VLBA) which is attached to 
your VLBA data. and found that it
includes only one tone!  exactly as the relevant PC table does. So VLOG, 
PCLOD, PCCOR work correctly.
So the VLBA  create PCALS only for one tone!!!
It happened because there is a maximum for the total number of tones.
AND THIS MAXIMUM is 16.
Your experiment has 8 IFs for LCP and 8 IFs for RCP, totally 16 IFs, 
what requires at least 32 tones.
Those 32 tones were switched to  the maximum 16 (one tone for IF).


Leonia



Enno Middelberg wrote:
> Dear Leonia,
>
>
> so when the PC table does not match the data, is this a problem with 
> the data in 
> http://www.vlba.nrao.edu/astro/VOBS/astronomy/jul07/bm261/bm261cal.vlba.gz? 
>
>
> The PC tables I tried to use were made from that file using VLOG, so 
> either the pulse cal data itself does not match the visibility data, 
> or either VLOG or PCLOD are not doing the right thing.
>
> Who would be the right person to talk to about this?
>
>
> Best regards,
>
> Enno
>
>
>
> Leonia Kogan wrote:
>> As I told, the 8 pairs of frequencies =16 are expected at each row of 
>> the PC table.
>> Your table has total 8 (instead of 16) frequencies at each row.
>>
>> The tones frequencies have to be located: 2 inside of each IF, one 
>> near left edge and another near right edge.
>> It is not a case for your PC table.
>>
>> Derive the left/right edges of each IF and compare them with the 
>> tones frequencies of your PC table.
>> You'll find the total disagreement.
>>
>> So PCCOR can not work with your current PC table.
>>
>> Leonia
>>