I'm thinking I may end up building something like this. I'd like to add a camera to this device that is pin pointed at the focal point of the dish. This way I can locate the source, and actually take a close up photo of it as well.
I think adding something like a BeagleBone Black with a hdtv camera device and the ability to record the audio from the electronics would be a nice addition to a device like this to help preserve what the device was looking at and what the noise sounded like at the time the test was conducted.
I was thinking about buying a device like the one noted in this article, but building one with the additional features I've been talking about here would be a fun and useful side project.