Every day between 10am and 11am, I see a drop in the UV/Brightness on my Sky unit. I was thinking it was a shadow from somewhere though I couldn’t think of where. I’ve been meaning to post about this for a while but I never seemed to be home (or, more importantly, remember) to take some pictures of …

If you can figure out which skewer may be shadowing at that time, remove that one and see what happens.

Scary stuff… that’s going to involve climbing up on the hot tile roof during the heat of day. Times like this I wish I had a 30’ ladder.

How large in diameter are the skewers? I just posted pictures of the WF BDA in the announcements post.

Zooming in on the picture and comparing to the one you posted, I’m guessing the skewers are no more than 1.5 times as wide the ones on the WF BDA. [image]

Maybe I can test this with a Sky I have.

When I get home this evening I’ll pull out a spare bamboo skewer and measure it for comparison.

the sensor itself is probably just a very very tiny chip. but there is a diffuser on top of the unit. That window is - just guessing - 20 mm wide. I guess that one of your anti bird spikes is just darkening the window. This pattern matches that of a small shadow passing over a round window. At first…

So my skewers are 2.8mm in diameter so about a 1mm wider than the “official” spikes. :slight_smile:

Odd drop in UV/Brightness measurement

Tempest Owners

gizmoev August 3, 2020, 10:01pm 7

More details about the spikes here.

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Odd drop in UV/Brightness measurement

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