[evlatests] EVLA Hardware

[Jim Jackson]

This is a long shot but I'll bring it up just in case.  Is there any chance 
the spectral inversion in the D351 is being set wrong.  In the eventual 
configuration, there is a mixer in the BD path of the UX converter that 
will cause a spectral inversion when it is switched in. Is it possible 
something in the software is setting this bit in the D351 to compensate for 
this even though the converter is currently hardwired to bypass this mixer?

Jim

At 06:13 PM 5/3/2006, Rob Long wrote:
>The L302 with the latest software revision has been installed in Ant 13, 
>L302-1 slot and appears to be working.
>
>We spent the afternoon looking into the U/X converter cabling and the 
>L302-2 performance on Ant 13 to try and understand why we can not fringe 
>at K and Q bands, IFs B and D.  All cables were correct and 
>bandshapes/power looked good at the output of the T304's using a spectrum 
>analyzer.  We used several frequencies to determine any offset  in the 
>test equipment and then verified that the L302-2 was locking properly 
>every time.  We commanded up and down in large and small steps and the 
>L302 appeared to lock properly every time.  Total power and switched power 
>at the T5 seem to be reasonable for IFs B and D and if the L302 is off 
>frequency, it would have to be a small value that I may have trouble 
>resolving on the spec an.  After talking with Ken, I'm unsure of what to 
>look at next. ??
>
>Due to some other work and testing that I needed to finish on the fire 
>alarm/shunt trip system, I did not get the L302-2 (from ant 13) installed 
>into ant 18.  I have everything else ready to provide 4 IFs, so I will 
>head out early in the morning to install the L302 into ant 18 and bring up 
>IFs B and D.  I hope to have this complete before 10:00.
>
>Rob
>
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