[evlatests] EVLA tests, Dec 15 2005

[Rob Long]

I hope that you meant ant 16 only worked at C-band.  The FE guys found a 
blown fuse (after installing a new distribution box) and replaced it. 
The F320 was then set up and everything appeared to be OK.

Rob

Ken Sowinski wrote:
>                         EVLA Tests, Dec 15, 2005
> 
> We are still recovering from all the HW activity of the last few days.  
> 
> 1.  ea16-l302-2 was in standby and had to be rebooted before it worked
> again.  The Mloop claimed to be out of lock.
> 2.  Antenna 14 worked only at C band.  No backend power perceptible at
> any of the other bands.  It turned out to be a blown fuse.
> 3.  Antenna 14 IF C was not very happy: low SD voltage and low
> correlated signal.  The consensus is that there is a downconverter
> problem.  Running the attenuator up and down in 6 dB steps does not
> give the expected behavior.  No matter how much attenuation in the
> path, the T5 ALC is always pegged in the large signal direction.
> 
> Because of the time spent tracking down these problems and discussing 
> causes,not much else was done except to set delays again for antenna 
> 14, and 16 at C band.
> 
> For the last half hour Walter prepared a file which steps through bands
> in various combinations to see what systematics we can discern in the
> phase jumps previously reported.  When this file begin 16 BD was dead
> and this was traced to the L302 in standby once again.  I rebooted it
> once again.
> 
> I understand that the 14C downconverter will be looked at Monday morning.
> 
> Barry and Hichem spent the afternoon at the VLA working on controlling
> VLA antennas.
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