Vector Graphics and Tang ended their discussions.

Under an agreement in principle announced in February, Eric Tang, representing a group of companies, would guarantee repayment of $1.7 million of secured debt on which the financially troubled Thousand Oaks-based microcomputer maker is in default. In exchange, the Tang group would have received a major stock and voting position. Vector also reported that it has signed an agreement in principle with Dual Systems Control of Berkeley for the merger of Dual into Vector. Dual Systems is a privately held corporation that manufactures and markets a 16/32 bit, Unix-based multi-user computer system.