The original idea behind PX was to have a small, compact, easy to send ltz1000 reference. Not more. With it in mind someone have the ability to compare/verify his 5.5, maybe 6.5 dmm in the 10 voltage range. This was not, at first, as i understand, to test the ref itself in long sessions, to get the reliability and characteristic curve, except as a side effect. One should test its own dmm better as with this chinese ones. So someone take this test, and ship it to the next interested for same simple thing. Same with this resistors, see if your dmm out and how much. The star shipping methode gives the sender, in this case vindoline, the ability, to check the ref for next shipping. In my oppinion, the ref ist robust enough, for input voltages between 12V and 15V for same output voltage, and protected against polarity reversal. The output should be save for >= 10Mohm impendance and not shortcut protected. These are the only conditions.
In the course of time, however, further requirements arose from participants that the reference behavior of the measurement should be recorded, and without temperature and humidity sensor with timestamp this would not really make any sense. So Jason kindly sat down again and developed an additional kit.
To make long words short, now we are sitting in front of the px, and realize that it is not robust enough for all this, and compare it with tin's reference, which plays in a completely different league. Yes, that's right. But px wasn't meant to be that way in my opinion. Actually, this should also, in its own original compact form, as my suggestion, without all the fuss around, go on its own quick journey.
Ok, i'm not at once in the usa club for now, so consider this as a suggestion on my part, hold it simple.
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