lspci |grep -i ralink
which for the A2 should give:
05:03.0 Network controller: Ralink corp. Device 5360
Wikidevi references a patch to the rt2800pci module (part of the rt2x00 driver) but I found no explanation on how to apply this to a Ubuntu 12.04, and it took some time to find out. The patch seems to apply to Kernel 3.4, but Precise uses 3.2. Ubuntuforums has a thread on the topic and one posting explains how to patch a download of compat-wireless for kernel 2.6 manually.
Instead of going that route, I wanted to give the patch for the 3.4. version a try, and on the way document a solution that would be easier to reproduce. The compat-wireless releases can be found at http://wireless.kernel.org/en/users/Download/stable/ , the patch is linked from http://rt2x00.serialmonkey.com/pipermail/users_rt2x00.serialmonkey.com/2012-May/004942.html . Putting that together:
wget http://rt2x00.serialmonkey.com/pipermail/users_rt2x00.serialmonkey.com/attachments/20120507/e2072201/attachment.bin wget http://www.orbit-lab.org/kernel/compat-wireless-3-stable/v3.4/compat-wireless-3.4-rc3-1.tar.bz2 tar -xjf compat-wireless-3.4-rc3-1.tar.bz2 cd compat-wireless-3.4-rc3-1 patch -p1 <../attachment.bin ./scripts/driver-select rt2x00 make sudo make install sudo make unload sudo modprobe rt2800pci
With this, the card should be recognized and start to work. I suspect that the compilation of the module has to be redone each time, the kernel is upgraded.