This thing changed my life

http://olcayonder.awardspace.com/www.yahoo.com.cool.things.byyourfriends41.php?kefu

Lesson learned

Well, despite the fact that my slider dolly is effectively complete (still need to permanently attach the follow focus servo), I still feel the need to improve upon various parts. Such as the home built 5v regulator circuit. I know that the 7805 chip is only meant to only handle a max of 1A, and that many times you are best attaching a heat sink. Ok, I attached a heat sink, but i may have been pulling more than a single amp into my servos. I realized that the heat sink got hot weeks ago. I only realized just how hot today. While feeding wires through right after playing with the slider dolly, my right ring finger barely touched the heat sink. And I now have a second degree burn on said finger. I added a second heat sink to the first, and measured the temperature with a small kitchen temperature probe: well I stopped measuring after it passed 250 degrees. Keep in mind I burnt myself when there was less heat dissipation. So I took off both heat sinks, and bolted the chip directly to the frame with the original heat sink on the other side of the frame. So now heat is moving through the aluminum frame in addition to the heat sink. I didn't bother testing that, instead I added a powered 12v heat sink/fan combo (40mm) onto he frame above where the regulator is mounted. While it's not directly on top of the chip like the frame/heat sink combo is, i figured this would help deal with the heat dissipated into the frame itself. I measured the temperature again, moving every servo as much as I could, and barely made it to 102 degrees. As soon as I stopped, it began dropping back to about 97 or so (ambient temp is about 85 right now in the house). I even touched the chip when it was at its new warmest temp, and barely noticed it. Lesson learned :D

Sean Watkins
Apokalypsis: (Greek) to unveil, to make known.