"WW" == W Watson writes:

WW Joseph Lazio wrote:

WW ... 1. Select source as Wide Double, two point objects appear in
WW the IP

First, what do you expect from selecting a wide double? Hint:
What's the Fourier transform of two delta functions located at (-x,
0) and (x, 0).

WW One for a single dirac. Dunno for two off hand*. It's been a long
WW time since I needed to know. Nevertheless, what is used in
WW unimportant to understanding the operation. Getting a decent
WW working example is what I'm after. That's what I'm after.

GIGO. I'm trying to ask you to understand what the possible answers
might be. If you understand what the possible answers might be,
you'll have a better sense of what's being displayed and when the
answer might be correct.

WW 2. Set the Lat to 45.0. Press Enter to make sure it's set. Use
WW the slider bars at the bottom to set the Dec to 0.0 and the HAs to
WW -5.1 (top slider) and +5.1. You may not get +/- 5.1, so do what
WW you can to be close.

Note that the default telescope is the ATCA, a southern hemisphere
telescope. Setting the latitude to +45 deg. means that you are
trying to observe a source below the horizon. I suggest leaving it
set at ATCA or choosing WSRT, another east-west array.

WW Well, yes, but I specified Custom. Presumably, when I say 45
WW degrees I'm specifying the location of the antenna, a Custom
WW antenna. I specified the source at a + declination. I would thin
WW it would be visible.

Yes. I still think sticking to an east-west array (ATCA or WSRT)
would be a good idea until you understand what's being shown.

WW Yes, seems fine, but it was also suggested that I should use an HA
WW from +/- 12 hours. I posted a response to that. It doesn't seem
WW possible (...) with the setup I used in the example. It would be
WW good to understand why I cannot get +/- 12. Object position?
WW Antenna E-W spread?

I suspect that you misread what somebody else suggested. Without
checking, my recollection is that the suggestion was to look for a
full track, so a total hour angle duration of 12 hour or +/- 6h.

Stop and think about it for a minute: A duration of +/- 12h doesn't
make much sense. An hour angle of -12h occurs when the source is on
the other side of the Earth. Not until the source reaches an hour
angle of roughly -6h does it even begin to rise. Same for positive
hour angles: At roughly +6h, the source begins to set.

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