Convert fake Unicode to real UTF-8

I've been searching for quite some time now and tried several functions, but didn't find a solution. I hope somebody can point me in the right direction. The problem: Russian text is entered through a web form. It's a rather badly administrated external webserver with old versions of everything, so I can not set the table to UTF-8. In the MySQL-Table the text gets converted to something like "Га" as an ASCII text. Using PHP I need to get the text out into a plain text file, as a real UTF-8 string. How can I convert this? All the conversion methods from PHP that I tried failed, as the text seems to really consist of the individual ASCII chars like "&", "#". Therefore, a normal to-unicode-conversion doesn't change anything. Thanks in advance, Andreas Jakl