Expresscard Power Supply Options

[simmac]

Help Please

I have the new macbook pro and I've got an expresscard with 2 FW 400 and 1 Usb port.
I would like to buy the apogee duet what needs the power from the FW port what the expresscard doesn't have. On my Fw 800 is running my external hard drive.
My question is ,can I use a general power supply what can give 12 V or do I need a special one?

I'm a touring musician and I'm in the UK right now and I didn't find anyone how could give me the answer.
In London in the main Apple store they even didn't know what is the the Oxford Chipset .................... anyway.

Thanks everyone

[FastEddy]

1) No question there is power drain from your hard drive and/or your "bus powered" audio devices ...

2) All modern notebooks with FW ports Will Shut Down Power to the FW ports (and USB ports), whether built in or on a plug in card, when the battery level drops, or even when the battery is fully charged. (This is a feature to make the batteries last longer, MacBook, HP or Dell, no matter.)

3) Without knowing the specific make/model of your FW (express) port card, you can and should obtain the correct 12 volt power supply to assist your laptop with this power dilemma.

My advise: See http://firewirestuff.com/power.html ... Note that there are two choices. I would get them both! The cigar lighter choice cables directly into that "extra" FW port on your hard drive, to give it power and this power will progress upstream to your FW sound equipment as well, if they are all on the same chain (this is a part of what "peer to peer" & bus power means).

Re: http://firewirestuff.com/power.html ... Whether you are totally mobile and just need the cigar lighter type booster, or you go to the studio as well and plug in the wall, the extra external FW power supplies will do the trick for more than 95% of FireWire devices = 12 VDC output, center positive, 0.25" dia. connector = the FireWire Trade Organization standard for FW power ... BUT check your express card to be sure, otherwise plug into your hard drive cable port as ALL name brand hard drives use this FireWire power standard.

Mercenary Announcement: That's My Web Site, I make money from it. You can possibly find these parts from other sources, but we do the "due diligence" to make sure ours are compatible with the http://1394ta.org specs.

This post has been edited by FastEddy: Thu 26 Feb 2009, 06:15