At 02:35 PM 9/6/2011, Rocket J Squirrel wrote:
>Does anyone have a suggestion for a two or three outlet USB power
>"strip" that can be mounted to a surface, such as behind the
>driver's seat, and which operates off 12 VDC?

The plug-in adapters are the best choice.  They're inexpensive, and
they consume essentially no power when idle.

I installed two extra cigarette lighters in the back so I'd have both
USB and 12V available.

http://mira.sbw.org/photos/20110808/P1000387/

For most USB devices, I prefer this Griffin dual adapter that gives a
completely flush look:

http://www.amazon.com/exec/obidos/ASIN/B0042B9U8Q/sbw/

But I also carry this Kensington dual adapter, with one 2-amp socket
to keep my visitors with iPads happy:

http://www.amazon.com/exec/obidos/ASIN/B003PU01M4/sbw/

The trouble with the USB "strips" (hubs) I tried is that they don't
reliably charge devices unless the hub is plugged into a
computer.  That's just stupid, in my opinion.  I'm still thinking
about fabricating a passive USB hub with several 2-amp outputs, buck
converters for efficiency, and proper idle power management.

https://twitter.com/sbw/statuses/2522118294

Originally, I fabricated a 7805 adapter and buried it in the dash,
with a cable coming out to hook up USB devices.  But it consumed more
power when idle than I liked, so I took it out.

>... it's an annoyance to find the stupid 12VDC > 5 VDC USB converter
>to plug into the socket.

I leave mine plugged in all the time so they don't get lost.  I
installed extra cigarette lighters so 12V is still available.

In fact, I have two cigarette lighters buried in the dash, one with a
Griffin USB adapter and one with the Garmin power adapter/traffic
receiver.  I bring those cables out through slots I cut at the edge
of the ash tray, to power the dash-mounted devices:

http://mira.sbw.org/photos/20091122/SN852283/

>Everything I do is switchable. I like managing my power. I have an
>ammeter mounted in the cabin and I'm not afraid to use it.

The best switch is one you can't forget to turn off.

But I like my ammeter, too:

http://mira.sbw.org/photos/20110809/P1000402/