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East tester ET432 vs Der EE DE-5000 Comparison
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TimFox:
Old-style "carbon composition" high-resistance resistors fall off dramatically in resistance with frequency:  the talc grains mixed with the carbon grains to increase the resistivity "short out" the carbon capacitively at high frequencies.
Resistors that have a helix cut into them to increase the resistive length will have a less dramatic effect due to the capacitance between "turns" of the helix.
Resistors with a "bulk" structure are better, but it is difficult to achieve a high resistance value in a normal-size package.
Many years ago, faced with this problem in TH resistors, I found "carbon ink" resistors from IRC to be the best at frequencies between 2 and 10 MHz, but I don't think they are still available.
My requirement was to achieve the maximum equivalent parallel resistance, since the parallel capacitance was part of the tuned circuit, where the resistor was required for DC bias purposes.
Some thick-film resistors (without helix) are similar.
Def461:

--- Quote from: NoMoreMagicSmoke on June 26, 2023, 04:19:32 pm ---Carbon resistors it is expected behavior that the resistance changes with frequency. You have to test with a precision film resistors that do not change resistance within the 100khz frequency.

--- End quote ---

Thank you :) I mean than manufactirer's EE demonstrates measuring with carbon :)
I guess I will film another video for him, with unpacking Vishay TF resistor and the direct measuring
NoMoreMagicSmoke:

--- Quote from: Def461 on June 26, 2023, 06:08:54 pm ---
--- Quote from: NoMoreMagicSmoke on June 26, 2023, 04:19:32 pm ---Carbon resistors it is expected behavior that the resistance changes with frequency. You have to test with a precision film resistors that do not change resistance within the 100khz frequency.

--- End quote ---

Thank you :) I mean than manufactirer's EE demonstrates measuring with carbon :)
I guess I will film another video for him, with unpacking Vishay TF resistor and the direct measuring

--- End quote ---

You are having the same run around I got. I had to provide them with the exact part number of the resistors I was using, and a demo of a different meter measuring it correctly before they finally admitted they reproduced the issue themselves.
ExaLab:
Below the accuracy graphs of my unit ET432.

They were done using Vishay Ultra High Precision Z-Foil Resistors (0.005%) up to 100kohm and a calibrated 0.1% metal film resistor for 1Mohm.
The instrument I have is well within the manufacturer's specifications almost everywhere. The only critical point, as observed by other users, is at 100kHz on the 1Mohm value where the accuracy is borderline (but still within spec...).
Remember that for resistance values higher than approximately 10k, in order to minimize the error, the most appropriate equivalent representation to select is the parallel circuit.
ExaLab:

--- Quote from: ExaLab on July 10, 2023, 08:55:07 pm ---Below the accuracy graphs of my unit ET432.

--- End quote ---

Just to complete, the accuracy graph for a 10Mohm metal film resistor.
As expected, excellent behavior up to 40kHz and -8% drop at 100kHz (but still within spec.).

What to say more? The instrument is not very performing @ 100kHz for resistance values higher than 1Mohm.
However, in my opinion it remains an excellent LCR analyzer!!
More, the manufacturer provides a very complete user manual, full of information especially in relation to the accuracy of all the parameters measured by the instrument.
This is another plus point that should not be underestimated...
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