EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: thewyliestcoyote on February 20, 2016, 10:59:02 pm
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Hello,
I just purchased 2 34401a. One is a Agilent and the other is a HP with the red and black terminals. The HP one is when measuring systems the measurement seems noisy but settings to a reasonable value. The Agilent one measures the final value right away. Is this common or is there something wrong or out in the HP unit. The resistance measurement is where it is most noticeable.
Thanks,
Wylie
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Under the Measurement menu A, there is the option to set the resolution. There are permutations of 4, 5, 6 digits with slow or fast measurements. I have read somewhere that one of the differences between the HP and Agilent units is that they default to different "resolutions" when powered-up. I have the Agilent version and it powers-up in "Slow 5 digit" mode.
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Its interesting that they are different but I had set the resolution to 6 digits fast for both of the units. This was one of the first things that I had checked.
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The older 34401A have been reported to have front/rear switches going bad. It may not be your problem, but you can check it by shorting the inputs on 2W ohms and set it to the lowest range.
Work the switch back and forth to see if it changes.
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ManateeMafia,
Thanks for recommendation,
I can not seem to find evidence of this failure mode.
I would describe the problem like a the charging and discharging of a RC filter with some added noise. For a jumper wire short it starts at 3 ohms and settles to 40 milli-ohms with some noise over the course of 2 to 3 seconds.