The Audio Analyzer UPL16 can be used in system applications in different ways: UPL16 together with Digital Radiocommunication Tester CRTx This application is ideal for type approval and development labs. For CRTx the software package CRTKAUD is required to operate also the speech coder of the CRTx, available for FR (full rate), EFR (enhanced full rate) and HR (half rate) test mode. The test cases are started from the user interface of the CRTx, the UPL16 is controlled via IEEE bus. The results are displayed on the UPL16 and transferred to CRTx. Together with the UPL16, acoustical measurements are now added to the large variety of tests provided by CRTx. UPL16 as part of GSM Simulator TS8916 The combination of UPL16 and CRTx is fully integrated in the TS8916 system. Performance and operation, concerning the control of UPL, activation of test cases and speech coder via CRTKAUD, as well as result handling are practically identical on CRTx and TS8916. UPL16 together with Digital Radio- communication Tester CMD52,55,65 or CMU200 This is the ideal and cost-effective combination for testing the acoustical quality in development, quality assurance, production, etc. The CMD or CMU sets up a call to the mobile via the RF link. Then the test cases are started from the user interface of the UPL16 and the results are displayed on the audio analyzer. For some of the tests, the speech code (FR mode) is needed, which has to be implemented in the CMD or CMU.