The 11683A Range Calibrator is specifically designed for use with the 435B, 436A, 437B, 438A, 70100A, and E1416A power meters. It allows verification of full-scale meter readings on all ranges, as well as meter tracking. Simply connect the cable between the power meter and calibrator. The CAL ADJ control on the power meter is used to set the meter to full scale on the 1 mW range. The calibrator and meter are then stepped through the other ranges verifying accuracy within ±1% plus noise and drift. Has polarity switch which tests the Auto-Zero circuit. Calibration uncertainty: ±0.25% in all ranges. Power: 100, 120, 220, or 240 VAC +5%, -10%, 48-440Hz, less than 10 VA.