The test set described in this paper allows complete quantitative characterization of all dc operational amplifier parameters quickly and with a minimum of additional equipment. The method used is accurate and is equally suitable for laboratory or production testDfor quantitative readout or for limit testing. As embodied here， the test set is conditioned for testing the LM709 and LM101 amplifiers; however， simple changes discussed in the text will allow testing of any of the generally available operational amplifiers. Amplifier parameters are tested over the full range of common mode and power supply voltages with either of two output loads. Test set sensitivity and stability are adequate for testing all presently available integrated amplifiers. The paper will be divided into two sections， i.e.， a functional description， and a discussion of circuit operation. Complete construction information will be given including a layout for the tester circuit boards