Joined:
May 2003
Posts: 4389
Location: Capital District, NY, USA Minor Outlying Islands | Fun science test for hygrometer accuracy:
If you really want to know if your hygrometer is right do this:
Gather these Matierials-
Large zip lock baggie
1/4 cup salt
1/16 to 1/12 cup water
juice glass
hyrgometer
Follow this procedure:
Mix salt and water in the glass
Put into zip lock bag with the hygrometer
Seal it
Wait 8-12 hours
In a closed system with damp salt the RH is ALWAYS 75%
Adjust your hygrometer reading accordingly.
I bought 2 hygrometers
http://www.musiciansfriend.com/srs7/g=home/search/detail/base_pid/420981/
and
http://www.stringsbymail.com/catalog/accessories/default.asp#hygro
The second one is the same as the humicase hygrometer sold on musicf'ers and cost $15.
I found the P3/Humicase to be more accurate @ only being off 1%
The planet waves one was off by 3%
Not a problem though, just remember how far off the reading is. |
Testing a hygrometer