Anyone any experience of charging by hand?
Pros and cons?
Hi Matt!
I have. I've owned a half-dozen variations on the standalone wind-up hand-cranked charger.
The ones I've tried involved a *lot* of crank-winding for not much electricit/run time, and the step-up geartrains were molded from nylon and soon wore out.
There were the ones where I pulled a string repeatedly, much as one would pull the starter rope on a gas-powered lawnmower engine or chainsaw.
There were the ones where I turned a crank till blisters formed on my fingers.
The only one I found to sorta-kinda work had a coil spring a bit like the old Baygen FreePlay radios...and the spring broke near the end, where it was anchored and flexed repeatedly.
I've foresworn these things for now. At most, I got just a few more minutes of talk-time from them for a whole lotta effort.
I have had better luck with external booster-batteries I can pre-charge and carry in a pocket, or a spare (charged) phone battery, or a small solar panel with accumulator battery, the bicycle's charging system, etc.
I haven't given up on the concept, just been plagued by poor executions of it.
I *do* think the wind-up charging mechanisms in small radios seem to be much better made than the standalone hand-cranks, based on my own dissections of several examples. The gear-trains (source of most of the trouble in the standalone models) are generally more robust and the charging circuits more efficient. Do be aware, however, that many of the better charging units of this type don't charge directly. Instead, a number of them charge a storage battery that in turn charges your gadget. This can lose storage capacity over time. he charge cycles aren't very even, and they tend to sit in storage a long while, both of which an compromise battery capacity.
The other issue with these things is it doesn't take much energy to run an AM/FM radio or a couple low-power LEDs. In comparison, smartphones consume a *lot* of power and have battery capacities and chargers to match. Many of the newer models require 2.0A chargers (mine does) to achieve ~2-hour charging times from flat. That charging time doubles at 1.0A and quadruples at 0.5A/500mA. That's a lot of cranking.
I'd really like to see a dedicated, quality clockwork generator or gravity-pull generator made small and light enough for cycle-touring. I commented on such here:
http://www.thorncycles.co.uk/forums/index.php?topic=3918.msg19657#msg19657 Though I haven't used them myself, I see Eton/Grundig have made some charging radios in the past and so have Baygen. Both these were several cuts above the standalone units that gave me such misery. See:
http://www.ukdapper.co.uk/eton-fr350-wind-up-emergency-radio-p-7533.html ...and...
https://www.youtube.com/watch?v=q7ThHkDPAgo...and...
https://www.readymaderesources.com/cart/alternate-energy/baygen-freeplay-flashlights/freeplay-radio-tuf/prod_5438.htmlReviews of more models here:
http://crank-radio-review.toptenreviews.com/ Be sure to check for a USB *output* port.
Here's a hybrid external battery-crank charger that would likely work better than a standalone version:
http://www.amazon.com/ForeverBattery-KA710-Wind-up-Portable-Rechargeable/dp/B00B4H3K50One of my favorite topics. If you find something that works great, please let us know!
All the best,
Dan. (...who has always been interested in such things)
