With concentrators such as troughs or dishes, a blocking shadow can be placed in front. The shadow just covers the two inner leds when aimed at the sun. Similar to the shadow on the chace http://tamilo.info/language/cell-phone/2382.php tracker. I have used a band of metal about.5 in width at about 6 from the led3. If the led3 is used for e-w tracking the band is oriented n-s.
Woodworking Crafts 039 - May 2018 » Hobby Magazines | Free Download Digital Magazines And Books