Breaking News
Comments
Newest First | Oldest First | Threaded View
<<   <   Page 2 / 2
Tom Murphy
User Rank
Blogger
Re: Shady Business
Tom Murphy   7/23/2013 6:22:00 PM
NO RATINGS
I know that's what he meant, Caleb, but I was confused by this part:

The MBED reads voltage from two small photovoltaic cells placed at right angles to each other. It rotates until the voltages on the two panels match. However, Davis found that this did not work in the Arizona sun as well as it did on his Florida workbench. The sun was too bright, and the difference between the panels was too minimal at any angle.

 

That made me wonder, if the Arizona sun was too bright, then why not make it less bright with a filtering lens? Wouldn't an opaque shade cast a longer and longer shadow as it tilts, thereby throwing off the direction more and more?  I'm not getting that part.

Caleb Kraft
User Rank
Blogger
Re: Shady Business
Caleb Kraft   7/23/2013 6:15:44 PM
NO RATINGS
The entire point was to make them uneven so that the array would shift to put them back in an even state. Without the shade, both panels reached saturation at all times. The shade gives a mechanical means of increasing the disparity between the two. 

Tom Murphy
User Rank
Blogger
Shady Business
Tom Murphy   7/23/2013 6:06:43 PM
NO RATINGS
I wonder, instead of using the shade, wouldn't it have been better to simple put a light-absorbing filter over the photovoltaic cells?  The shade would shift in angle, exposing more of one cell than the other, while a filter would keep them even -- replicating Florida in Arizona. 

<<   <   Page 2 / 2


Flash Poll
EE Life
Frankenstein's Fix, Teardowns, Sideshows, Design Contests, Reader Content & More
Rishabh N. Mahajani, High School Senior and Future Engineer

Future Engineers: Don’t 'Trip Up' on Your College Road Trip
Rishabh N. Mahajani, High School Senior and Future Engineer
3 comments
A future engineer shares his impressions of a recent tour of top schools and offers advice on making the most of the time-honored tradition of the college road trip.

Max Maxfield

Juggling a Cornucopia of Projects
Max Maxfield
19 comments
I feel like I'm juggling a lot of hobby projects at the moment. The problem is that I can't juggle. Actually, that's not strictly true -- I can juggle ten fine china dinner plates, but ...

Larry Desjardin

Engineers Should Study Finance: 5 Reasons Why
Larry Desjardin
39 comments
I'm a big proponent of engineers learning financial basics. Why? Because engineers are making decisions all the time, in multiple ways. Having a good financial understanding guides these ...

Karen Field

July Cartoon Caption Contest: Let's Talk Some Trash
Karen Field
144 comments
Steve Jobs allegedly got his start by dumpster diving with the Computer Club at Homestead High in the early 1970s.

Top Comments of the Week
Like Us on Facebook
EE Times on Twitter
EE Times Twitter Feed

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)