interfacing hih humidity sensor with pic
Hi Ammamon,
I have heard of a method of doing this with a resistor. I haven't had time to try it yet, but I think it will work well, and do plan on trying it.
You scrape the outside layer off of the resistor to expose the carbon to the atmosphere. The resistance will vary with humidity, and you can use this in an op Amp circuit to measure and scale it to a reasonably linear output.
I have used the Humerel sensors, which work fairly well, but also need to be put in circuit with a 555 timer, which will then output a frequency which is dependent on humidity.
Also the sht1x, or sht7x can output both temperature and relative humidity by SPI, without additional circuits, but they tend to cost more. I have seen these for as low as $10 USD, and as high as $29
Best wishes,
Robert