November 29 (SeeNews) - A Bulgarian consortium controlled by Telcom Engineering and involving Telelink Infra Services, a unit of Telelink Business Services [BUL:TBS], has embarked on a 108.4 million levs ($57.5 million/55.4 million euro) project for the development and overhaul of the interior ministry's TETRA digital system and radio relay network, Telelink Infra said on Tuesday.