Tektronix AM503 The AM503 Current Probe Amplifier a

The AM503 Current Probe Amplifier allows display of current on any oscilloscope having 10 mV/div sensitivity, 50 ohm or 1 Mohm input, and (for performance to full bandwidth) at least 100MHz when using the A6302 (sold separately) or 50MHz when using the A6303 (sold separately). The amplifier attenuator has 12 calibrated steps in a 1-2-5 sequence, and the knob-skirt is illuminated to indicate current per division.