Hey All,
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I noticed what looked to be a zero issue with my 435B, so I thought I'd run it through the zero carryover test (OSM 4-6) to see what was going on.
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While the meter meets all the ranges given for zero carryover, it occasionally doesn't meet the requirement:
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4. Press the front panel ZERO and wait for the meter indicator's position to stabilize. Verify that the DVM reads 0+/- 0.9 mVdc. Release the ZERO switch.
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My output seemed quite noisy, so I used the statistic function to look at it over 100 samples, and what I saw was:
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- Max 0.533 mVdc
- Min -1.006 mVdc
- Avg -0.150 mVdc
If I had been quick to look at it, then I could have moved on to the next part of the test and never noticed that over some time it exceeds the +/- 0.9 mVdc requirement.
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Should this be less noisy??
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The only fix from the manual is to change the factory selected resistors A4R12 & A4R16 (the A1 assembly is a recommended factory replacement), and it does pass the actual +/- span for each step of the range control so I'm hesitant to make any changes to those.
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Any thoughts or guidance appreciated.
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TonyG
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