Topic: Ipod power questions

[ts]

Ok. I tried to ask this question in playback http://taperssection.com/index.php?topic=70234.0, but maybe I'm not asking it the right way.

I have a Creative Playdock which was sold as an accessory to the JB3. It provides power to the JB3 via it's internal 12V SLA, which makes the unit a really nice completely portable playback device. Both Creative and Cambridge state that the Playdock CANNOT power an ipod.

My question is why not? If it can use the internal 12V to power a JB3 and other MP3 devices, it must have a converter knocking 12 down to correct voltage for the JB3 and other MP3 players, but not the ipod, so all I would need to know is what does the ipod require for power and can I use the internal 12V with a different power converter or maybe the same one to a hacked ipod USB cable to get this playdock to power my ipod.

Does this make sense?

[dnsacks]

I believe usb devices are powered by 5 volts.  If your Ipod will charge off of a usb connection (some older ones will only charge via firewire), it should be possible to put together an interface that would feed the ipod power via the creative's 5volt output via an ipod>usb cable.

[ts]

Thats what I was thinking. If the ipod will handle 5 volts, I could try hacking an ipod USB cable to connect to the 5 volt output that is on the playdock. I wonder how many wires are inside the ipod cable I think the output cable on the playdock is 3 wire. For some reason Cambridge is saying it's not possible.

[beathydrolysis]

USB delivers delivers a maximum of 5 volts.  If your Ipod charges via USB then it should in theory be able to take up to 5 volts.  JB3's run on approximately 5v as well (even though they do not charge via USB).  However you can get away with running the JB3's on less, I do 4.5v in the field.  I don't know if the same can be said for the Ipod.  Regardless it is very likely that you would be able to hack a cable to deliver 5 v from the playdock to the Ipod since the output on the playdock is 5 v.  Please be warned about getting the right polartiy though.  You can really mess up hard drive players by giving them the wrong polarity.  The first power mod I ever did was for an external battery pack for my iriver H320 and I messed it up hardcore.  Other than that, I'd say go for it.