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In Tuesday's SSS meeting i promised i would ask some questions of a
wider audience. This is the 3rd of 3 emails.<br>
<br>
We are trying to make the OSRO user interface in the OPT look as
similar as possible to both the existing VLA correlator setup already
in the OPT and the PST's presentation of the OSRO modes. Scientists
who attend SSS mtgs are helping us craft this; see latest mock-up at: <a
href="http://www.aoc.nrao.edu/%7Edlyons/osro-mockup3.html">http://www.aoc.nrao.edu/~dlyons/osro-mockup3.html</a><br>
<br>
On the <a href="http://www.aoc.nrao.edu/evla/astro/osro.shtml">OSRO</a>
page Table 1 is used for full polarization setups in which there are
two independently tunable subbands. In the mock-up you'll see that for
each subband we're allowing independent Doppler tracking. This is made
possible by placing each subband in a different sampler output pair
(A/C vs B/D).<br>
<br>
This works well except in Ka band. In Ka the A/C IF goes only as low
as about 32GHz. This means w/ the approach of putting each subband in
a different sampler output we cannot support certain requests (eg,
subbands at 28GHz and 29GHz). Of course, we could put such
combinations in the B/D pair, but only one of these can then be Doppler
tracked.<br>
<br>
Since OSRO is pretty restrictive already, will we tell users that some
combinations are not supported?<br>
<br>
David<br>
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