[evlatests] crossed-hand delays

[Bryan Butler]

ahh, right, what i was missing was that it's not the fact that the noise 
source 'couples equally' into the two polarizations at the same strength 
that is important.  sorry...

	-bryan


Ken Sowinski wrote, On 11/18/10 13:48 PM:
> On Thu, 18 Nov 2010, Bryan Butler wrote:
>
>>
>> the noise sources are different for each polarization.
>>
>> -bryan
>
> No, Bob is right. I determined the crossed-hand delays by
> looking at the crossed-hand autocorrelations just as he
> suggested. I checked a few crossed-hand cross correlations
> as well, and they agreed.
>
> Long ago, I did this with the Modcomps and was able to verify
> that crossed-hand delays optimized this way gave the correct
> answer with a strongly polarized source (3C286), and conversely
> that this method gave the correct answer when delays were
> optimized in continuum using 3C286.
>
>
>> Bob Sault wrote, On 11/18/10 13:34 PM:
>>> With the switched noise source measurements, presumably the source
>>> couples into both polarizations equally, and so cross-delays and
>>> RL phase could be measured using this mechanism (ie correlating the
>>> R and L of the noise source on one antenna)?