Step 8: Building The Interactive Box - Basic Parts 1
3 10k Ohm Resistors
2 100k Ohm Resistors
1 10k Ohm Potentiometer
2 Transistors NPN BC 548
1 Transistor PNP BC 558
1 ceramic Capacitor 100nF
1 electrolytic Capacitor 10uF
switch and wires
Each number refers to one picture:
1. This is the simple and ordinary lunch box, which serves as the container for our future interactive target.
2. One centimeter away from the bottom of that box (which will be our top) we need to place a plywood to fix the phototransistors and the technology to make them work. Measuring is tricky because of the round corners – use another box and copy the square for placing equally the transistors.
3. Here I placed a printout of my „helper“ on a 8mm plywood, drilling holes using a 1mm thin drill bit. Make sure to go straight down – this small drill is balanced, so that one can let gravity lead the way.
4. 72 holes later, the first job is done.
5. Now you can re-use this printout, cut away the center square to mark where the 1cm spacer (and protector for the phototransistors) will be glued to. Use a dimensional lumber to get an equal result.
6. The 1cm² lumber I cut into two outside and two inside pieces. I drilled them too, to support the glueing with pin nails (without heads). Just to avoid the thin wood the crack. Later cut off enough of these pins, so they wont show on the other side when driven down.
7. The ready frame, the 72 holes visible, this side already nicely colored (to increase the sensitivity of the transistors).The transistors have endings, that have unequal length, plus being the shorter. I fixed them with Super Glue, making sure they are all aligned /adjusted in the same direction.