Went out to buy a dry cabinet today. Mostly motivated for more storage space than actually needed to keep dry.
Ended up with a Digi-Cabi DB-036 (it's a 30L) from John 3:16 for $118/-.
The relative humidity stayed at 20% after running it for a day, that's even when the door was left opened for a couple of hours. That where to buy valtrex over the counter convinced me that the psychrometer is not working. True enough, took it apart and immediately saw one piece of resistor like part has came out. Made a random guess and "plugged" it back into one of the many set of holes, and viola, it worked! 🙂