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current probe calibration
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gogoman:
Hi  I  soldered a 50ohm resistor to the end of a coax and monitored  the voltage and current across the resistor.
Next I stepped the freq and compared the measured current to the calculated, the current probe was off by 20-30%

Is this a validate measurement technique?

thanks
HighVoltage:
How did you measure the voltage and current?
And what are the measured values?

What current probe did you use?
What frequencies are we talking about?
What does the signal look like?

Without the basic information, it is hard to give any feedback or advise.

gogoman:
the probe is  Tektronix P6021
signal Source is a sine wave
The voltage probe is across cross  the resistor, the resistor is encased in the current probe jaw.

The signal from the current probe is a sine wave. At 40mhz there voltage peaking.
the I R Drop  does not is equal the  peak-peak  scope voltage

thanks
David Hess:
That can work and it is how current probes are calibrated but the signal source needs to be leveled and the resistor should be one with low inductance and capacitance.  I think you will have to extend the ground side of the resistor and place the probe there instead of over the resistor to reduce electrostatic coupling at high frequencies.

The Tektronix 067-0559-00 current probe test fixture uses a transmission line environment.  I might try to construct something similar out of double sided copper board and a chassis mount BNC connector.

http://w140.com/tekwiki/wiki/067-0559-00

Read the P6201 calibration instructions to see how it is used.

http://www.produktinfo.conrad.com/datenblaetter/1100000-1199999/001171294-an-01-en-TEKTRONIX_P6021A_AC_STROMTASTKOPF.pdf
tautech:

--- Quote from: gogoman on August 12, 2018, 07:05:26 pm ---the probe is  Tektronix P6021
signal Source is a sine wave
The voltage probe is across cross  the resistor, the resistor is encased in the current probe jaw.

The signal from the current probe is a sine wave. At 40mhz there voltage peaking.
the I R Drop  does not is equal the  peak-peak  scope voltage

thanks

--- End quote ---
Do you have the 6021 termination module #011-0105-00 or type 134 amplifier ?
One or the other must be used in conjunction with a P6021.
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