Hi everyone,
Not sure if it’s the right category…
Well, as said before, I build a dynamo bike light.
It is based on the circuit n°8 from pilom, whith additional standlight and rear light (that is still being built).
admire the paint skills (note that the switches on pic1 and pic2 are not the same. I did not draw everything).
The main supply wire passes through the front connector (the thin rectangle, before the front light) so that if the light disconnects, the electronics won’t have to suffer the open-circuit over-voltage of the dynamo (100+ V downlight, the legend says)
Resistor values may not be the real ones though.
I won’t explain the left part, pilom did it better than me.
The pilom electronic is in a 3D printed case, nothing special.
The frontlight and standlight capacitor are in a convoy s21 host.
The idea is to charge C4 through D10, with 2 leds voltage.
When the wheels stop, C4 discharge in 1 led through R4 (well, all the time actually, but it is negligible).
At the start, all the current passes through D7, and charges C4 through D10. When C4 voltage rises, it begins to illuminate gradually D9. When C4 is charged enough, D8 kicks in.
It takes less than 1 minute at driving speed.
When I stop, D9 stays lit. The fact that C4 (7.5F) is in the front light host allows me to unplug it from the bike and use to take something in my bag for instance, or to go piss or anything you want. The light stays for hours. I estimate it to be easy to find in a tent even after a whole night. The light can be used for lighting very close for several dozens of minutes. Far enough to be seen at a red light…
For the rear light, C5 is also charged while driving. The whole thing is an astable transistor oscillator, which goal is to blink alternatively 2 rear light that I can put near the wheel axle, and under the saddle for instance. Actually, the flashing pattern is weirder than that, but the idea is the same.
The leds are Nichia 219c 4000k 90+ CRI, that look quite nice, this is my first led light so I can’t really compare.
The optic is a carclo 10510 lens : triple elliptical. The beam is far from flat, almost round. I talk about it in another post.
If I had to do it again, I would use the last circuit of pilom’s page, which uses less parts for similar perf.
I would certainly use Cree XPL HI. They give a much flatter beam pattern, the 219c’s will be a pain in the ass to make road-friendly. Plus, I won’t really need high cri. This is a bike light, not a surgeon headlamp…
I anybody has questions, don’t hesitate. I will put real picture is the next days.
This is mostly useful at night, where power is not the first concern
… but I also want to cycle on the road and have all the dynamo lumens 
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