TiN there is "repair per incident" that is "just" 2300 USD so you are not going to spend others 4000 for any repair.
Repair usually does not include calibration, which is in case of A3 board replacement is required. Of course, one can go with regular calibration, which is much cheaper than standards one for ~2.5k, so there are options for any requirements.
Even in business you don't have unlimited budget and all you spend must produce a ROI. This is especially true if you are very small.
Sure, that's why I said cost of ownership meter like 3458A, rather than price of having the box. Just after few years of use and maintenance, cost of calibrations alone will exceed MSRP of meter itself.
HighVoltageThe guy that does my official calibrations claims that the older HP units are much more stable because of those ceramic chips.
May be we should put an older and a newer model next to each other and compare?
This is case which needs a photo first , too see those magical ceramic parts
. Reader's unit I was fixing recently was the oldest I ever saw, 1989-1990 parts with SN 04xxx, and yet it uses all the same plastic opamps as ones made in 00's.
So before we speculate any more, let's get solid info what is different. So far even photo of newest A3 2015 year from KS site shows same ceramic ADC hybrid and plastic opamps around.
Old units are likely more stable just due to aged parts and reference
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CAL?72 test shows only ADC stability. Meter still can have other issues/drifts on other functions/ranges, but show perfect CAL?72 data.