[evlatests] Antennas 26 and 18 ...

[Rick Perley]

    Good news for Antenna 26 -- all is normal now.   The 'square wave' 
effect in phase found by Emmanuel last week has been repaired. 

    However, antenna 18D has the 'multiple amplitude' level problem -- 
also known as 'shredded levels'.  Something in the DCS is not right here. 



   

Rob Long wrote:
> We found numerous problems with frame alignment in all 4 deformatter 
> cards for antenna 26 this morning.  We initially tried adding extra 
> cable to the 128 MHz clock splitter in the antenna which seemed to help 
> IFs B & C.  After checking into the deformatter rack, we discovered that 
> several fan trays had blown fuses and the deformatters for antennas 26 
> and 24 were running especially hot!  We had looked at this issue once 
> before, made some measurements, and upped the fuse rating on all fan 
> trays in the deformatter racks today.
>
> The good news is....once the boards cooled down (and we rebooted the 
> D351-A), the frame alignment errors for all IFs dropped to zero on 
> antenna 26.  We will continue to keep an eye on these fan assemblies to 
> ensure that we now have the correct fuses installed.  If someone could 
> let me know if this cures the "phase jumping around" problem I would be 
> very appreciative.
>
> Rob
>
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