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Submitted by: Wilfried Adam (fried19@web.de).

After having inherited a big batch of new old stock single, dual and quad op-amps of unknown condition, I was faced with the task of testing this batch before pressing the op-amps in to service. So I cobbled together the test circuit given in the enclosed schematic. The test circuit has been designed to handle single, dual and quad op-amps in DIL packages. A green LED indicates that the op-amp section is OK. A simple cheap DMM connected to one of the outputs 1 to 4 indicates the offset voltage produced by the connected op-amp section whereby the reading needs to be divided by 100, i.e. 1V on the DMM corresponds to an offset voltage of 10 mV, 0.1 = 1 mV and so on. With an offset over 10 mV, the green LED turns off. 5 V power supply op-amps can be accommodated by adding the orange coloured circuit section and switching to 5 V operation. However, this 5 V mode is currently untested (lack of such op-amps in my junk box).