ipod / cellphone power
 

Hi all, first thread here so be gentle with me OK?

I'm planning a solo trip next year from the UK to Nordkapp. I've managed to sort out the difficult logistics such as the lack of ferry services (going to travel freight instead - much cheaper and there's a route from Hull to Kristiansand).

However, I'm looking to make sure I've got power to the essential devices on the trip [ipod and cellphone]. Since my bike doesn't have a cigarette lighter style socket installed, and to be honest I'd rather have hardwired cables fitted under the seat I'm in a little bit of a dilemma - whilst I can still just about wield a soldering iron, my knowledge of electronics per-se kind of petered out after leaving uni some *mumble mumble* years ago.

If I obtain flyleads for my phone and ipod with 12v car connectors on the end which I then hack off - is there anything that I need (aside from the fuse) to wire in? If anyone has a handy circuit which I can work to that would be an even greater bonus :clap:

iPod is a standard G3 iPod with Dock and the phone is a Sony Ericsson K800 if it makes any difference. The iPod will be cabled into my Autocom for the audio and the phone will be hooked up for audio via Bluetooth so only power is required.


Many thanks in advance,
Stumpy.

For the phone, you should find a car charger cable, that will allow you to charge directly from the bikes 12V.
You can also find car usb chargers for the Ipod which charges on 5V.

If you don't want the cigaret lighter socket, you just cannibalise the two mentioned circuits and bulid them into a box with your own plugs or wires on. Just be sure to protect the electronics from humidity and vibrations.

As both chargers are available for very little money, it doesn't really pay, to start making the circuits on your own. The carchargers also have the necessary circuits to protect your mobile and ipod from changing voltages and spikes that are always present in automotive power.

Welcome Stumpy! I'm in the process of trying to find a waterproof 12V accessory socket instead of trying to hard wire my devises. I think most 12V phone chargers are built into the plug. I'm sure you could probably take it apart carefully and hard wire it, although I have never read of anyone doing it. I have no idea about the iPod, I'm hoping to pick one up soon though. Let us know what you come up with.

My little GPS is hard wired to the bike. I bought a 12v adapter then took all the guts out of the plug and soldered on a fused fly lead. Found a little box at Maplin that fitted and filled the box with potting compound. It's been on the bike for four years now without problem.

I'm sure the same method would work with almost anything.

what amp fuse did you use? I want to do pretty much exactly the same thing as the original poster but am unsure

I think it's only a 2amp. I calculated what the expected draw should be then rounded up to the next fuse capacity I had kicking about.

I did worry a little about heat build up with the electronics being potted (the original adaptor had some vent holes) It hasn't been a problem though. I think the potting compound may have some "heat sink" properties.

Although I say "hard wired" my electrical bits connect using the plugs that come with an Optimate type battery tender. They are also the same plugs and sockets that are used for radio controlled car batteries so are easy to get.

I have also made up a lead for giving the battery a boost of another vehicle or helping someone else.

It can be a bit of a struggle finding out-of-the-way places to fit things away from heat, dirt, damage.

BYT

what is the calculation for the output? The battery on my phone is 1050 mAh 3.7V, how do I work this out?

edit: googled it, it's /1000 so I think I need a 10.5 amp fuse?

Stumpy

I would get this ROADKING - Electrical - Plugs&Connectors - Hella Plug and Socket and wire the socket to an accessory circuit. This is known as a Hella type, the same size as on BMW and Triumph bikes.

Mount the socket facing down/rearwards or somewhere dryish yet accessable. BMW ones cost more but have flaps to keep some water out.

Wire the plug to a cigarette lighter size socket (Halfords, Maplins etc). You can get 12v car chargers for phones and i-Pods which have their own safe fuse.

I use a wire of suitable length to keep the cigarette socket, charger and gadget in a pocket to charge up as I ride. It will also reach into a Top Box (locked!) to charge while parked.

1A*3,7V=3,7Watt this is if you charge the battery in one hour

3,7W / 12V= 0,33A. So if you charge in 1 hour you need a 0,5 A fuse

The purpose of the fuse, is to protect the wires in case of shortcircuit, nothing else.

ahh k thanks for that

Clarification
 

First mAh or Ah are Ampre Hours ... so both current and time are involved ..

(m is an SI multiplier in this case m = milli = *1/1000 as in milli metres = metres /1000 )

1 Ah = 1 Amp in 1 hour .. or 10 Amps in 1/10 of an hour ... or 1/10th of an Amp for 10 hours ... all 1 Ah

---------------------
pbekkerh has assumed that the conversion from 12v to 3.7v is 100% effecient .. that assumption can be very wrong.

If the charger you use is a cheap simple series regulator type - then the current going in is a little more than the current going out .. so you'd need a fuse over 1 A... It will depend on the charger you use .. and how 'flat' the battery is .. some chargers when presented with a dead flat battery draw lots of current.. best to look at the charger specification!

hmm I'm gona try this but also buy a solar charger for backup (or when the bike is off), they look pretty good, you can charge the solar battery from usb too

Well, I also assumed that the charger would charge in 1 hour, but most would use 4-5 hours, so the current would be 1/5. There will not be any higher start current, as all charger nowadays are current limited.
I also raised the calculated value from 0,33 to ,5A so it will probably be correct.

1A for charging an Ipod or mobile is over the top, especially because both can be charged from a USB connection, that can't deliver more than 0,5A at 5V so thats max. 2,5W!

Of course my first calculation is an example, as I don't know the actual values for his chargers.

you can buy a small charger, that charges the mobile from a single AA battery. I am looking for one for the Ipod too, meanwhile, I use a MP3 player with 1 exchangeable AAA battery.

I prefer this method, as I can charge in the tent, on a plane etc.
example:
New AA Battery Travel Mobile Charger for Motorola Phone - eBay (item 170265732062 end time Oct-01-08 04:32:02 PDT)

Hey thats awesome, thanks.