This may be something where talking to the HAM community will be more productive than talking to the hacker community, the first step would be to reliably track it using an antenna suitable for the frequency range and checking if it is emitting anything at all before attempts to contact it would make much sense (once you have a signal to home in on it is a lot easier to prod it rather than to prod blindly until something responds).
Keep in mind that this frequency band is not exactly unlicensed territory, you're smack in the mobile aeronautical band according to ofcom. So listening is likely ok but you may need a permit to transmit at that frequency and it is not necessarily the same frequency at which the satellite will receive it's input (typically it is some other frequency to enable full-duplex).
http://www.g3pho.free-online.co.uk/microwaves/history.htm
Doing a 1/4 wave trackable parabolic dish for something a little under 3m wavelength is very much achievable (and is not even close to microwave frequencies, 3m is huge!). If you want better efficiency you could use a larger dish but I think that it would be easier to up the power on the transmitter than it would be to make a dish 4 times that surface that rigidly tracks an object in LEO. That's quite the little bit of hardware engineering you'd have to do there. Even a few degrees 'off' would likely ruin the signal so precision is key and a large dish catches a lot of wind.
The amateur radio bands go all the way to 1mm:
http://en.wikipedia.org/wiki/Amateur_radio_frequency_allocat...
According to the wiki page a team at UCL was planning to try, but the link to Roger Duthie's blog is dead. Any idea if they achieved anything?
Update:
Missing blog post content is at [1], courtesy of archive.org. Looks like they built some comms hardware. The full series of posts relating to Prospero is at [2]. Interesting read.
[1] http://web.archive.org/web/20121026003633/http://blogs.ucl.a...
[2] http://web.archive.org/web/20121026003618/http://blogs.ucl.a...
Yes, but have not found anyone who is also serious and also need some funds to pay for necessary equipment.
The National Archives has lots of good stuff about Prospero, including:
"Operational control of Prospero": http://discovery.nationalarchives.gov.uk/SearchUI/Details?ur...
Consider just raising some prize money and then announcing a race for the first group to have confirmed contact with the satellite, and get out of the way?
Also, I would prefer not to do the race as the real motivator for me is the thrill of doing it and the fun of learning about how it was done.
It probably could be done as a Kickstarter and I'm guessing for the low £1,000s (radio, antenna, probably some interesting pre-amp/filter stuff).
I'm really really rusty on VHF, do not have any required licenses and all my HAM contacts have dried up due to old age so that's pretty much all I think I can help with. The most I did in hardware terms in the last 6 months was to make an old Unitra grammophone work again, not quite in the right league :).
http://upload.wikimedia.org/wikipedia/commons/7/7b/Parabolic...
And a suitable radio set for 'stage 1' (find the thing), and then a suitable transmitter and some modem (probably doable using a SDR or even an audio card connected to the transceiver) to actually talk to it.
http://cargocollective.com/ORBIT-OFFSITE_DOWLATSHAHI/Prosper...
I love the design of the Black Arrow rocket. It looks like something out of a 1950's sci-fi movie.
Also, looks like someone beat you to the punch back in 2011:
http://upload.wikimedia.org/wikipedia/commons/f/f9/Black_Kni...
Now, who wants to join me in trying to talk to Britain's only self-launched (i.e. launched with our own rocket) satellite: http://en.wikipedia.org/wiki/Prospero_(satellite)? Most of the documentation is in the National Archive (I have copies).