Digital thermohygrometer

I wish to buy a digital thermohygrometer. The instrument will be
used by students of a school for book conservators for climate
surveys, and to calibrate the old fashioned thermohygrographs we
still use for long-term recordings, and for didactic purposes. The
qualities needed are: easy to use, reliable, and that will last for
several years; it should be possible to re-calibrate it in an easy
way. It should not be too expensive. If you already use one of those
instruments, I would appreciate your suggestions.


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                  Conservation DistList Instance 15:35
                 Distributed: Monday, October 29, 2001
                       Message Id: cdl-15-35-024
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