uwezi

Nice project - what your project is missing but was present in the "real" projectors is a blanking of the light source during the transitions. You could probably add this feature by directly switching on/off your flashlight...

There is one thing which your (or any) calibration will not be able to correct and that is the apparent zero-offset of the ADC. All parts of the input signal below about 0.1 V to 0.2 V is lost - that is almost 5-10% of the full measurement range!

no, criss-crossing the wires would not help - just take a square post-it note and draw the connections and the magnet polarities for yourself and you will see. The problem is that the cubes are supposed to be mounted together on either side - you never know which side ends up as top and which as bottom - only diodes will solve this problem...

Thanks for the work - I just dissasembled my owm bulb...However, one small correction: "The copper is the antenna." - no it's not. The antenna is on the circuit board under the white paint, just outside the metal can. The copper strip provides a grounding between the can and the case of the bulb.

no, it wouldn't work, because the electrical polarity as compared to the magnetic would have to be reversed on either side and then the cubes could not be rotated upside down - see the attached sketch

I just recently learned fro0m somewhere else about the salt and the glue. All the tips are great and I will immediately follow up on organizing my sandpaper!

Very nice tutorial!I still prefer to use OpenSCAD for most things, this is how it could be done there:edge = 25;spacing = 1;sphere_r = 28/2;$fn = 120;union(){ difference() { cube([edge,edge,edge]); translate([edge,edge,edge]/2) sphere(r=sphere_r+spacing); } translate([0,0,sphere_r-edge/2]) translate([edge,edge,edge]/2) sphere(r=sphere_r); translate([0, edge/2, 0]) cube([edge/2, 0.1, 0.1]);}

even though he has not described it, but it appears that he has built a bridge rectifier from discrete diodes - you can see it among the images in Step 5. With this design you will have to use a bridge rectifier because you will have to use opposing magnetic poles on either side of the cubes otherwise...

If you have your own 3D printer you can create a relief of this kind without signing up using the free software OpenSCAD...

while being more flexible for the task at hand even the cheapest Arduino-clone is about 100x more expensive than a 4017...

I like your idea and project, I have done something similar some years ago - the wall wart is on the other side of the dry wall in a closet.I am not concerned about the electrical safety of your project, but rather concerned about a fire hazard, keeping the wallwart in a small hidden volume inside the wall. I see a risk of overheating and smoldering which could go quite some time unnoticed...

Thank you for this documentations, however it's not a L293D chip on these boards: the pinout does not match! But the manufacturer of these boards has been very careful to strip down the chip markings... but the L293D would not contain MOSFETs either... I found an image with complete chip code on Alibaba, it's either an MX130B or MX1308.

if - only if! - this wind turbine would be anywhere close to producing 2-3 W of electric power (which could charge a smartphone in a mere 3 hours) it would produce at least a comparable drag on the bicycle. Just imagine it dangling on one side of the handle as in the photos ;)

He will not be able to destroy (or charge) any lithium battery with this reverse fan. You might get a certain open-circuit voltage out of a "generator" like this, but there is no way it will deliver any significant amount of power (current times voltage).You have just to compare a high quality hub dynamo which delivers 2.4 W with this fan - you cannot turn a wheel attached to such a dynamo by just blowing, yet riding along you don't notice the extra resistance. What happens with the fan if you actually try to extract power is that it will simply not rotate anymore...