Hi all, As I have mentioned previously, I am designing a temperature and humidity control system for my university lab that I am working in. Several dsPIC controlled remote terminal units (RTUs) will be placed in self contained chambers. These RTUs will provide a means to log and control temperature and humidity. Within the chambers are special fungi that require a high relative humidity (RH) level to grow effectively - sometimes even close to 100% RH. I am concerned that water from the air may condense on the PCBs and cause problems (such as undesirably conducting electricity, and so on). Should I be worried about this? If so, what can I do about it? Also, are there any other potential problems that I should be aware of for running home-made electronic equipment in a high humidity environment? Will a crystal/crystal oscillator deviate enough from it's desirable frequency in a high humidity environment to cause serial communication issues? --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .