The hybrid computer system can be used for investigation of offline digital control techniques for any modeled system. System model can be patched on the analog computer and different digital control techniques as PID, optimal state, fuzzy logic, etc. can be tested using the associated digital computer. Such system is very useful for development of control programs for critical systems. A typical system consists of a PC, an I/O card, an anlog computer and number of tests and control programs. Provided flexible software minimizes the need for external test equipment. Introductory manual provides information about the system and how to use the system for number of test cases.