[evlatests] Ka-Band S/N 2 on Antenna 2

[Dan Mertely]

I swapped the LCP/RCP output cables on the ant02 Ka band
FE this morning @ 09:00.  -Mert


Bob Hayward wrote:
> Glad to hear it is alive.
> 
> On the polarizations being swapped, I was a bit puzzled to find that if 
> I disabled the LNA's on the RCP side, the detected output on the LCP 
> channel would drop. And vice versa. I was hoping it was just a mix up in 
> the harness carrying the bias voltages to the amps and not a cross in 
> the RF signals. Looks like it is the latter. My guess is that the 
> phase-shifter might be rotated by 90 degrees from the desired 
> orientation. I think the output path after the amps is OK (since its not 
> easy to cross the WR-28 waveguide runs).
> 
> For the time being, we'll swap the RCP & LCP cables at the outputs of 
> the receiver when we get a chance...
> 
> -Bob
> 
> 
> Ken Sowinski wrote:
>> It works fine even if it is a bit hot.  Focus and pointing
>> are pretty close and there is a respectable fringe amplitude.
>> Delays have been set relative to antenna 4.
>>
>> But...  ea02 has its polarizations swapped compared to ea04.
>> I would argue that ea04 is correct because if has fringed
>> with the other antennas at K and Q bands.
>>
> 
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