[evlatests] Ant 13 UX Converter (and Ant 21)

[Jim Jackson]

Rob and I just looked at this.  The monitor point for the RCP LNA 
voltage in the Antenna 13 UX converter is reading 0.00 which 
indicates there is likely a problem with the RF plate in that UX converter.

While comparing it to other antennas, we also noticed that Antenna 
21's UX converter is dead (missing +17V switched power supply to the 
RF plates). Hopefully that is just a blown fuse.

The appropriate folks have been notified about both of 
these.  Someone should be looking into these problems tomorrow.

Jim


At 04:56 PM 7/26/2007, Rob Long wrote:
>IF-A seems to have some TP, but I just noticed that the T304-A levels
>are set at '0' so we may just be seeing noise.
>
>Rob
>
>Ken Sowinski wrote:
> > On Thu, 26 Jul 2007, Rob Long wrote:
> >
> >> Ant 13 appears to need it's T304-B attenuator values reset for Q-band.
> >> I'm not sure why, but IF-B seems to need much less attenuation (like
> >> input=3 and output=7).  I'm not sure what criteria is used to determine
> >> the proper levels on the B/D downconverters, but B is not working at
> >> Q-band.
> >
> > I think the problem is a little deeper.  I asked Tom
> > to write up antenna 13 because there is no TP for IFs
> > AB at both K and Q bands.
> >
> > At K band there is not enough power to the sampler even
> > with the attenuators wide open.  Q band is hotter and
> > can just be made to work by adjusting the the attenuators.
> > I suspect a problem in the UX converter.
> >
> > Ken
>
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