ABD wrote: "By the way, I think I erred when I reported the "operating range" as up to 85% RH, non-condensation. That was referring to the unit itself, not to the probe."
That is correct. All instruments that I've ever dealt with, be it $100K microwave analyzers to simply DMMs and temperature meters, ALL have a spec for operating temperature and humidity FOR THE ELECTRONIC DISPLAY ITSELF, apart from any attachments. For obvious reasons... Any condensation whatsoever inside the device will almost assuredly change the electrical circuit properties and cause erroneous readings. Even though some companies use a 'conformal coating' on the entire circuit assembly to protect it from condensation and other contaminants, it is still likely to cause errors in the measurements... If you open up most any older Hewlett-Packard instrument, you will immediately see that they almost always used a thin gold layer on all copper PCB traces... This was done so that the instrument would maintain its sensitivity and accuracy over time, and in harch environments. -Mark
