Allsky1pi aka allskypi
This is part of the new allsky1pi camera system, specifically the ZWO ASI 120mc camera with its included wideangle lens, and a reaspberry pi model 3b. The camera is mounted on a wood piece to hold it up into the dome the the top cap of the housing.
The system was redesigned over the last month, removing 110VAC and having only a 5vdc powr supply for the Raspberry Pi and a variable 3-12vdc power supply for the 10ohm 10 watt resistor in the dome, to prevent condensation and to melt snow).
It was reinstalled on the evening of Wednesday 2002 February 12th and worked once the power was plugged in.
Over the last two nights we need to:
1) rotate the camera so that north is up again
2) increased the voltage on the heater. The last two days were set at 6volts. wattage = volts^2/resistance so that would be 6^2/10=36/10=3.6watts
If we put it up a notch to 9volts we should get
9^2/10=81/10=8.1 watts, or a little more than double. That should melt the snow and ice!
In the summer it can be turned back down again as the absolute temp is much less.
THe new housing, 4″ PVC by 12″ long (the old one was only 9″ long). The old housing was a little tight for space, what with cables, a pi, a pi power source, more cables, camera, etc. Not to mention 5 cm of water! Note for future projects: duct tape does not keep out water infiltration!
The 10ohm resistor is mounted on the top cap. The large centre hole is for the camera, the smaller holes were for air circulation, hoping that the heat of the raspberry pi alone would keep the dome clear.. it was not.
A ring of silicon went around the edge of the top cap, with the dome flange sitting on it. Less gaps for air leakage than in the past. Two screws with fabric washers keep the dome on the top cap.
The power connector is an automotive 12vdc two wire set with protected contacts to avoid shorting.