DIY dew heater

[jtlandreneau]

I've been swamped with dew lately on my newt, it's been killing all of my imaging sessions. on my little refractor I just have a constant heat applied via some nichrome wire sandwiched in layers of duct tape, and that works well. For the newt though, I didn't want constant heating hurting the mirror or inducing tube currents. Combine that with not wanting to spend a fortune on buying a heater, I set out to make my own.

so, with that in mind, using an arduino, some temperature sensors, and a temperature/humidity sensor, I wrote a little script that kicks a relay whenever the measured temperature is within 3 degrees F of the ambient dewpoint (calculated using the relative humidity and ambient temperature). The relay is fed by a 19V laptop charger that energizes a nichrome heating pad I made.

I'm going to post the build sequence soon after im done testing