Assid,

You need to supply 48v to the mic in the balanced mic supply.

You can buy some small pro mixer used from a pro audio store, or a new small pre-amp like http://www.behringer.com/MIC800/index.cfm?lang=ENG

or you can build one like Eric Wallin's at http://mysite.verizon.net/tammie_eric/audio/preamp2/preamp2.html

Even new, some of these mic supplies are like $50.