Testo 760 Series Multimeters - Testo 0590 7601, The Testo 760-1 digital multimeter has ranges for virtually all daily measuring tasks. Function keys replace the traditional dial, which gives easier operation and greater reliability. Measurement parameters are detected automatically via the appropriate use of the measuring sockets and are shown by the illumination of the appropriate function keys. Testo 0590 7601 760-1 Multimeter