Author Topic: Bike mounted USB Charger  (Read 82759 times)

Re: Bike mounted USB Charger
« Reply #100 on: 17 January, 2011, 04:52:51 pm »
On the big (computer side) USB connector, +5V and 0V are the outer pins, the two in the middle are data.

Part of the USB charging spec says that a charger should connect the data pins together (or via a low value resistor, but shorting together is fine) to indicate to the unit that it is being charged rather connected. So, if you build a cable that only connects the power pins, then the 705 goes into "connected" mode. This was a problem with some external battery packs - they only connected the power pins, so you couldn't use them to charge the 705 on the go. I knocked up special cables for a couple of people to allow them to use their old external batteries with the 705.

EDIT: see Re: Garmin 705 Extending Battery life

Re: Bike mounted USB Charger
« Reply #101 on: 17 January, 2011, 05:05:02 pm »
I'm slightly hesitating as that price would buy me another couple of portapower batteries. Three of those would be more than enough for PBP for the phone and GPS, and have neater cabling on the bike. But being fully self-sufficient power-wise also has its attractions.

A £3 ebay power pack that takes 4xAA batteries and pumps out USB 5v would be even cheaper. Indeed, I'll be carrying one as a backup should be SON die during PBP. (The backup light is powered by 4xAA batteries).

Je voudrais beaucoup des piles s'il vous plait...
"Yes please" said Squirrel "biscuits are our favourite things."

Gotte

Re: Bike mounted USB Charger
« Reply #102 on: 17 January, 2011, 05:30:53 pm »
So anyone know if any of these USB chargers will work off a bottle dynamo as opposed to a hub? If not my only option (I think) is to get the Nokia charger and a 2mm to mini USB converter.

Re: Bike mounted USB Charger
« Reply #103 on: 17 January, 2011, 05:33:42 pm »
So anyone know if any of these USB chargers will work off a bottle dynamo as opposed to a hub? If not my only option (I think) is to get the Nokia charger and a 2mm to mini USB converter.

I'm afraid I don't know. The last bottle dynamo I owned was in about 1980 and I seem to remember it created an awful lot of rolling resistance and didn't give out a very steady current. Of course they have no doubt improved since then!

Re: Bike mounted USB Charger
« Reply #104 on: 17 January, 2011, 05:37:12 pm »
A £3 ebay power pack that takes 4xAA batteries and pumps out USB 5v would be even cheaper.

That's what I used on LEL. The thing I disliked about it was the number of sets of part-used AA cells I ended up with; ISTR there was some problem with letting them run completely flat, so I'd always start a ride with fresh ones. But, it does have the advantage of being able to "recharge" from any little shop or garage (or PBP control; I'm sure somebody said that they sell AAs at them).

On Mille Cymru I used a combination of the portapower pack for on-the-bike charging, and a 4 cell 4000mAh LiIon pack (that I use for powering my transmitter when doing SOTA)  with a cigar lighter socket attached so I could use my Garmin car charger. That's got a lot more power in it the portapower pack, as long as it is stepped down using a reasonably efficient switching supply. I did half consider using this on the bike, but it's quite bulky.

Re: Bike mounted USB Charger
« Reply #105 on: 17 January, 2011, 05:40:56 pm »
So anyone know if any of these USB chargers will work off a bottle dynamo as opposed to a hub? If not my only option (I think) is to get the Nokia charger and a 2mm to mini USB converter.

Electrically is should be fine as long as it is a reasonable quality dynamo. They still have the problem of slipping on the tyre when wet and causing bad tyre wear (though some tyres, such as the Marathons, have a dynamo track on them to try to mitigate both of these).

What are you intending using this for? Multi-day touring, or just topping up the phone on a long ride/commute? For the latter, one of the portapower batteries would be cheaper and more reliable.

Gotte

Re: Bike mounted USB Charger
« Reply #106 on: 17 January, 2011, 07:06:09 pm »
I'm interested in it for longer touring when there's no way of charging my Hero via mains. I'm going on a wild camping tour of the highlands of Scotland later this year and we'll be out in the wilds for about ten days. I'd like to be able to charge my phone while riding, not only so I can read (got kindle on it), but also listen to music at the end of the day. GPS would be good, also. My battery last about six hours when I use GPS. I figure that I'd happily trade off some resistance for a charged battery.
Ideally, I'd go with a hum dynamo, but I have a 700c tourer that I'd probably also want to use it on when away in Europe, and two dyno-hub wheels for both bikes just make it too expensive.

Re: Bike mounted USB Charger
« Reply #107 on: 17 January, 2011, 08:53:19 pm »
I'm interested in it for longer touring when there's no way of charging my Hero via mains. I'm going on a wild camping tour of the highlands of Scotland later this year and we'll be out in the wilds for about ten days. I'd like to be able to charge my phone while riding, not only so I can read (got kindle on it), but also listen to music at the end of the day. GPS would be good, also. My battery last about six hours when I use GPS. I figure that I'd happily trade off some resistance for a charged battery.
Ideally, I'd go with a hum dynamo, but I have a 700c tourer that I'd probably also want to use it on when away in Europe, and two dyno-hub wheels for both bikes just make it too expensive.

Is there no way you can share a 700c wheel between the 2 bikes? My dyno hub wheel is soon to be a shared one. I can't ride both bikes at the same time and it is very quick to swap it over when needed. I'm very impressed with how little weight and resistance the Schmidt hub has added to my bike and the light it powers is very powerful. It's such an awesome fit and forget solution.

Re: Bike mounted USB Charger
« Reply #108 on: 18 January, 2011, 09:48:45 am »
I share the dynohub wheel between all of my sporty bikes but I can't use it on the 700c hybrid as the 42mm Marathon Winter tyres are too wide for the Open Pro rim (max recommended 28mm, can risk 32mm).

I don't think there's a sporty 700c rim that will cope with a range of tyre widths of 25mm to 42mm.
"Yes please" said Squirrel "biscuits are our favourite things."

border-rider

Re: Bike mounted USB Charger
« Reply #109 on: 18 January, 2011, 09:58:32 am »
Exal LX17s will.

are they "sporty" ? Dunno.  They're a tad wider than an OP but not that much,   but they're claimed to work with 25-54 mm tyres.   I'm sceptical of the upper end; they aren't that much wider than OPs.

I've used 35 mm tyres on OPs and they were fine. I did once run a 47 mm tyre on one but the profile was a bit odd.

Very nice rims, too.  Dead easy to build with.

Re: Bike mounted USB Charger
« Reply #110 on: 18 January, 2011, 10:09:30 am »
Exal LX17s will.

are they "sporty" ? Dunno.  They're a tad wider than an OP but not that much,   but they're claimed to work with 25-54 mm tyres.   I'm sceptical of the upper end; they aren't that much wider than OPs.

Hmm. 17mm internal width and Sheldon says: 25mm to 37mm. (Note: This chart may err a bit on the side of caution. Many cyclists exceed the recommended widths with no problem.)

I did forget to look at that chart before posting.

19mm internal width would be better, but then it'll be weighing a bit more than the 'sporty' 425g of an Open Pro.
"Yes please" said Squirrel "biscuits are our favourite things."

border-rider

Re: Bike mounted USB Charger
« Reply #111 on: 18 January, 2011, 10:17:59 am »
You might struggle with a 25 mm tyre on a 19 internal width

I've got one on the back of the TinOne and I split the tyre at the start of a 300 last year and scrounged a spare off the organiser.  It was a 25, and though it worked it had a very odd profile.

I'm fairly relaxed about fat tyres on narrow rims (within reason) - it's what a lot of MTBs have - but narrow tyres on wide rims is not so good in my view.


Gotte

Re: Bike mounted USB Charger
« Reply #112 on: 18 January, 2011, 12:19:57 pm »
Is there no way you can share a 700c wheel between the 2 bikes?

Not really - the two bikes in question are 700c and 26 inch. True, the 700c will fit, but I won't have any braking as the v-brakes don't fit the rim, and the wheel is more a road wheel than off road, and I'm looking to take my mountainbike tourer on more inaccessible routes.

Panoramix

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Re: Bike mounted USB Charger
« Reply #113 on: 18 January, 2011, 01:06:11 pm »
A £3 ebay power pack that takes 4xAA batteries and pumps out USB 5v would be even cheaper.

On Mille Cymru I used a combination of the portapower pack for on-the-bike charging, and a 4 cell 4000mAh LiIon pack (that I use for powering my transmitter when doing SOTA)  with a cigar lighter socket attached so I could use my Garmin car charger. That's got a lot more power in it the portapower pack, as long as it is stepped down using a reasonably efficient switching supply. I did half consider using this on the bike, but it's quite bulky.

This SOTA thing is awesome, we should put a motion at the next AGM to allow DIY to be validated by gonio just to see the reaction!
Chief cat entertainer.

Gotte

Re: Bike mounted USB Charger
« Reply #114 on: 18 January, 2011, 02:12:00 pm »
Here's another question, more about dynamos - if i get the Nokia bottle dynamo kit, will I be able to fit it to a dynohub later. What I mean is, I suppose, are the voltage outputs different with bottle and hub dynamos?

Re: Bike mounted USB Charger
« Reply #115 on: 18 January, 2011, 02:25:57 pm »
A normal dynamo - including most common hub dynamos -  is 6V/3W. Occasionally you'll find 12V dynamos, but these are usually very well marked.

You should just be able to use a hub dynamo in place of a bottle - but remember that a hub dynamo is running all the time, so you'll have to figure out some way of disconnecting the load (e.g. dynamo driven lights usually don't have a switch for bottle dynamos, but do have one for hub dynamos).

Kim

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Re: Bike mounted USB Charger
« Reply #116 on: 18 January, 2011, 02:30:17 pm »
The voltage from a lightly-loaded hub dynamo varies so greatly with speed that it's fairly safe to say that any device designed to work with a hub dynamo will be fine on a bottle, and presumably vice-versa.

Gotte

Re: Bike mounted USB Charger
« Reply #117 on: 19 January, 2011, 01:33:23 pm »
Thanks for that info. Much appreciated.

border-rider

Re: Bike mounted USB Charger
« Reply #118 on: 19 January, 2011, 02:42:00 pm »
With one proviso - if you use a Litespin bottle dynamo it has all sorts of weird conditioning electronics that make it look quite unlike a hub dynamo.

Re: Bike mounted USB Charger
« Reply #119 on: 22 January, 2011, 10:42:58 pm »
My Biologic Reecharge hub dynamo charger arrived today. I haven't tried to fit it as yet, but have had a good look at the instructions and all the bits.

It sounds pretty straightforward except for one thing, there is an extra A4 sheet with it with some further instructions contradicting what the manual says. It states that you musn't leave the regulator bit connected to the hub when you are not charging the Reecharge with it or it can be damaged by the current that has nowhere to go.

I am going to need to work out a way of switching the dyno output to either go to the light or to the Reecharge, but not both at the same time. I certainly don't fancy fiddling with spade connectors on the hub every time I want to turn the thing on or off. I was wondering if I ran a cable up the fork from the hub into some kind of switch that can select between light or charging (maybe an 'off' setting as well?). I could then connect the switch to both the IQ Cyo and the regulator unit of the Reecharge. Unfortunately I lack electronics-Fu so I am blissfully ignorant of the ins and outs of 6V switches that are weatherproof available on the market. If anyone has any ideas they would be gratefully received!

Gotte

Re: Bike mounted USB Charger
« Reply #120 on: 25 January, 2011, 05:34:38 pm »
Here's another question.

Would it be possible to simply attach a car mini USB charger or specific phone car charger to a 12v dynamo?

I suppose what I'm asking is, is the output the same from a 12v car output as a 12v dynamo, or does something else have to be added to make it work.

I only ask because I saw this one, which seems just that:

Pedal & Power

Only trouble is, no one stocks it, and the site doesn't sell it, which is not very enrepreneurial (or however you spell it)

Kim

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Re: Bike mounted USB Charger
« Reply #121 on: 25 January, 2011, 07:24:49 pm »
Would it be possible to simply attach a car mini USB charger or specific phone car charger to a 12v dynamo?

I suppose what I'm asking is, is the output the same from a 12v car output as a 12v dynamo, or does something else have to be added to make it work.

AIUI, the 12V dynamos also output unregulated AC, so it'll still need a rectifier and probably some regulation (the definition of '12V' when applied to vehicle electrical systems is fairly loose, but still not as extreme as the range of voltages you can get from a lightly-loaded bicycle dynamo (indeed, the nominal 6V dynamos will easily output 12V at reasonable cycling speeds if not driving a tungsten lamp - modern LED lights make use of this)).  The main advantage to a 12V dynamo would be more voltage available at lower speed.

In other words, no.

Re: Bike mounted USB Charger
« Reply #122 on: 26 January, 2011, 10:00:35 am »
I am going to need to work out a way of switching the dyno output to either go to the light or to the Reecharge, but not both at the same time. I certainly don't fancy fiddling with spade connectors on the hub every time I want to turn the thing on or off. I was wondering if I ran a cable up the fork from the hub into some kind of switch that can select between light or charging (maybe an 'off' setting as well?). I could then connect the switch to both the IQ Cyo and the regulator unit of the Reecharge. Unfortunately I lack electronics-Fu so I am blissfully ignorant of the ins and outs of 6V switches that are weatherproof available on the market. If anyone has any ideas they would be gratefully received!
Multi-position switches are the spawn of the devil. I've used, broken, cursed at and binned several on boats.

There are two main types; 'make before break' and 'break before make'. The difference is that, when switching position, does the switch make the new circuit before breaking the old.


TBH, I think you would be better off using some sort of connectors. More reliable and less likely to make a mistake. The sorts of connectors used for remote control toys are much easier to manage with gloves on and last longer.
These sorts of things:


You don't even need special tools to put them together. Easily bought from ebay, maplins etc.
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andygates

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Re: Bike mounted USB Charger
« Reply #123 on: 26 January, 2011, 10:54:19 am »
I'll take a switch with a nice rubber hat, any day.  That looks easily fumbled, sworn, and connected while full of rainwater.
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Re: Bike mounted USB Charger
« Reply #124 on: 26 January, 2011, 02:50:20 pm »
I'll take a switch with a nice rubber hat, any day.  That looks easily fumbled, sworn, and connected while full of rainwater.

Your Kinder surprise suggestion was genius :)