http://www.amazon.com/Analog-Hygrome...rds=hygrometerQuote:
Originally Posted by martin82531
Accurate robust and can be calibrated using a cheap easy salt test.
http://www.cigarsinternational.com/html/cig101_12st.asp
The salt test is accurate to about 1% RH few digitals are accurate to better than 5% and many are 10% some truly horrible poor quality are 15 or 20%.
The down side of this hygrometer is the metal plate on the back and the magnet. The plate is not well glued (I re glue with hot melt) the magnet is useless I use a rare earth one I actually place the magnet on the outside and hold through the enclosure. I use a strong 1/2 inch by 1/8 one personally.
http://www.ebay.ca/itm/10-Neodymium-...ht_2209wt_1398
martin82531 you need to delete some PMs!
A