Hi Biketool,

What a timing! I just returned full of questions from a 3weeks bike trip around Iceland testing my self powered n900 system and here you posted this at the same time. Maybe you can enlighten me ...

I have a SON dynamo hub with the E-werk. I bought it because it's the only device currently that can deliver 12V from a bike, and I'm planning to use that for charging a netbook. So far I only tried with the N900 and standalone chargers, and I'm quite happy of the 100€ investment (and the starbike.com service).

I don't have the additional cache battery sold with the Ewerk (52€ for 1400 mAh), because I had a small solar charger of 2200mAh (Vaude LP2200, http://www.rucksack.de/rubriken/arti...aign=ide/vaude) with cable input up to 7V/1000mA and USB output 5V which is even more functional. But the solar panel is so ridiculously "slow" that I'll have a look at others like Long March.

My setup idea charging was: dynamo -> E-werk on 7V/1000mA -> Vaude cache battery -> N900, that would receive a neat current, charge and play music to me while recording my GPX track with Mappero and display my speed and location.

However, the N900 refused to charge that way, whether I use the Nokia-provided USB charging cable from the cache battery or another cable. I tried powering the N900 directly from the Ewerk (this time set up on 4.9V/500mA, but I also tried 5.6V, and current up to 1000mA to simulate a wall socket charge) on an easy road where i could maintain a 20km/h speed (i.e. enough for the E-werk to deliver a neat current). In the best of the cases, the N900 would do this: the N900 would recognize the power (i.e. switch on if off, or have the battery icon pumping) and the lamp blink. But the lamp blinks green instead of orange, I had never seen that. After 2 green blinks, it stops. the N900 doesn't charge.

If i stop the power input and restart (i.e. I disconnect the cache battery or stop cycling), the same pattern will happen: 2 green blinks, then nothing.

Have you noticed this pattern? Or any other reader who tried to charge his N900 without the Nokia tools? Even though I always tried as well with the Nokia-provided USB cable at the end of the chain. Is the Long March working perfectly with the N900, switched on and off? And able to charge
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I ended up charging spares NB-5L battery (I have 3) with a universal battery charger (http://www.me2solar.com/pixo-c-usb-u...y-charger.html). I can recommend it, as it can take USB3 current (900mA) and even deliver 7.4V (for dSLR batteries) while having an input at 5V. The drawback of this was that I had to swap batteries every day, and the setup is fragile (the battery is kind of loose in that universal charger, but it's the point as it's supposed to accomodate any battery) on bumpy roads.
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For the handlebar case, I picked up the only model at the nearby DIY shop, a chinese 12€ case made for iphones, the N900 fits tightly, is waterproofed, the touchscreen works well and it hold toght to my handlebar even when the rocky roads made my back and butt sore for hours.
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It feels so good to have the comfort of the N900 tools (phone, gps, music, wifi) without getting off the saddle and without paying attention to the power (well, provided one cycle a decent amount of KMs every day). I hope I can solve that N900 not wanting to charge directly.
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Cheers,

jb