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> I'm completely out of my depths here but hear me out: could pulsars be observed with such a thing? That would definitely be the icing on the cake.

In principle, yes. But I think in practice it would be difficult at best. Pulsars become fainter at higher frequencies, and this dish looks relatively small. So I suspect that combination of factors would mean that there aren't many (if any) pulsars that one could detect with this setup.

> expected rotational frequency of the targeted pulsar and then shifting the phase until the signal is maximized?

A technique like this is one way to search for pulsars. Though you don't use trigger signals since you don't a priori know the pulsar's spin period. So you record data for a period of time, then try many timesteps over which to fold the data and see if there's a pulse at that period. I'm sure there's better ways now, for it to be done.

PRESTO is one of the major pieces of software used to search for pulsars: https://www.cv.nrao.edu/~sransom/presto/

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Yes, ONE telescope may not be able to adequately resolve a pulsar at that frequency.

But a /network of/ these telescopes, appropriately coordinated, that's a different story. And seems like a logical next step. You could use GPS conditioned timekeeping and standardized directional setup to coordinate data from multiple telescopes. We do that in some distributed physics projects like cosmic ray studies.

I'm not sure what you mean by "resolve"; are you referring to resolving the pulsar's pulse in time?

I was speaking more about the flux detection limit of such a dish (implicitly assuming the receiver could make sufficiently short measurements to enable folding of the data to detect pulses in the time-folded dataset). One could try to coherently sum the measurements from a number of telescopes to increase the signal to noise.

Alternately, one could also try to detect the pulsar by averaging over the pulse profile, but that still requires that the telescope+receiver sensitivity is better than the period-averaged flux density. But then you're risking confusion of other, continuum, radio sources in the beam.

It's still the case that most pulsars are much fainter few GHz frequencies than they are 1 GHz (e.g., https://arxiv.org/abs/1302.2053). Though there are likely selection effects (discussed in the linked paper), most of the pulsars we know about can be expected to be ~40x fainter at 10 GHz than they are at 1 GHz. The linked paper cites a 6.5 GHz survey that identified 18 pulsars (compared to > 1000 detected in the ~1.4 GHz survey).

I suppose it depends on what one's aims are, though. Someone wanting to only detect pulsars in general, it'd be easier to do at lower frequencies. But there's certainly some science to be done by observing them at higher frequencies.

If you want to do that at 140MHz, sure. But at 11GHz interferometry is -- despite being conceptually the same -- quite hard.