Dear Members, I purchased and received a 3701 line probe. I need your help to learn this probe. I attach its calibration data below for reference. Two types of calibration data, Impedance and Insertion Loss, come with the probe. Question 1: The impedance varies a lot over the frequency range from 9kHz (1,750.095 ohm) to 30MHz (566.456 ohm). Is this variation acceptable? I plan to use this probe to measure disturbance voltage at load terminals per CISPR 15. The second paragraph under Introduction of the 3701 manual (http://www.ets-lindgren.com/manuals/3701.pdf) states "The Model 3701 Line Probe presents a nominal resistance of 1500 ohms to all voltages on the line. The Line Probe also attenuates noise voltage, so a correction factor must be added to the EMI receiver readings to obtain the proper emission levels on the line." To me, 566.456 ohm is too far away from 1,500 ohm. Question 2: Is the insertion loss the correction factor mentioned in the paragraph quoted above? For example, if the EMI receiver reading is 20 dBuV at 9kHz, should I add 36.078 dB to it as my test data/result? Thank you for your time and look forward to hearing from you. Best regards, Grace Freq (MHz),Impedance (Ohms),Insertion Loss (-dB) 0.009,1764.095,-36.078 0.01,1750.831,-35.505 0.02,1539.087,-32.393 0.03,1526.762,-31.143 0.04,1525.608,-30.51 0.05,1524.686,-30.217 0.06,1523.528,-30.043 0.07,1527.384,-29.935 0.08,1522.35,-29.859 0.09,1523.744,-29.81 0.1,1522.031,-29.77 0.2,1521.142,-29.638 0.3,1520.676,-29.606 0.4,1520.399,-29.592 0.5,1518.446,-29.581 0.6,1517.75,-29.575 0.7,1516.088,-29.569 0.8,1515.104,-29.564 0.9,1513.197,-29.556 1,1511.712,-29.554 2,1486.775,-29.524 3,1450.57,-29.499 4,1405.686,-29.477 5,1356.307,-29.46 6,1304.82,-29.443 7,1247.061,-29.428 8,1175.883,-29.413 9,1118.001,-29.398 10,1069.605,-29.389 15,856.509,-29.35 20,708.009,-29.326 25,633.139,-29.297 30,566.456,-29.284 -
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