Switch both the [JOIN] switches to the OFF position Set all 3 level controls to maximum Monitor [AC OUT] on Column 1 Patch a 100Hz 5VAC triangle wave in to [INPUT 1] Adjust P101 for 5Vp-p at the output Monitor [AC OUT] on Column 2 Patch the triangle wave in to [INPUT 2] Adjust P201 for 5Vp-p at the output Monitor [AC OUT] on Column 3 Patch the triangle wave in to [INPUT 3] Adjust P301 for 5Vp-p at the output If you do not have access to an oscilloscope then a multimeter set to AC Volts can be used