LED Controller – production version 0.1

The time has arrived to move the LED controller circuit from the bread board to a real board. It was to be my first experience with relatively delicate soldering of quite a few connections. I stuck the few components onto the board and started soldering the underside.

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I realised after a short while that I shouldn’t have placed cables on this side at all because the soldering will break if any pressure is applied to them. Also, after some cables were already soldered it because difficult to solder more of them, especially those connections that already lay under other cables. Anyway, most of the cables in the photo above connect the 7-segment controller with the 7-segment display.

On the left side of the photo you can see the two common ground an 5V lines that I connected to the board. This was very convenient.

I passed the rest of the cables on the upper side.

One of the nice features of the board is the old green connector that I salvaged from an old PC board. In this photo I connected LEDs for verification, but when I’ll mount it onto the quadcopter I’ll connect the cables attached to the LEDs. Getting it out of the original board was hard and attaching it to this board was even harder because its pins were wider than the holes in the board. I filed them for a long time and finally decided to hammer the piece (gently) onto the board. This worked.

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And here is the board in operation.

I had to protect the cables running on the bottom side so I prepared a frame from two pieces of this soft plastic material whose Enlish name I don’t know. I cut the frame to be smaller than the board so that it will hold the board in place.

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When I replaced the test LEDs with real high-intensity LEDS I found the following problems:

  1. The high-intensity LEDs are rather dim. I didn’t debug this problem yet but I can think of two possible causes. One is that I used resistors that are too strong (220 Ohm).
  2. I may connected the transistors incorrectly.
  3. The transistors are not sourcing enough current.

I will have to talk to my friend Tomer about this problem.

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