The Scosche PassPort HomeDock ($39) adapts older, iPod accessories such as speaker systems and docks, to work with the iPhone and recent iPod models. Specifically, the PassPort steps down the voltage of older accessories from 12 volts to 5 volts, to address the fact that the iPhone and newer iPods models have ceased support for 12 volt charging.
The PassPort HomeDock measures 1 inch by 1.25 inch by 2.75 inches, and is designed to fit snugly into any iPod dock that uses Apple's universal dock standard (for example, docks that accept those little plastic dock inserts that came with your iPod). Docks and speaker systems that use their own proprietary dock design (such as the Harman Kardon Go + Play) aren't going to work with PassPort. The same goes for speaker systems such as the Altec Lansing iM7, which limit the height of the iPod (the PassPort adds an extra half inch to the dock).
Users of the popular Bose SoundDock (first-generation) iPod speaker system should be pleased to know the PassPort HomeDock is available in matching black or white, and comes with an extra bit of plastic that brings the adapter flush with the system dock.
Aside from allowing older accessories to charge newer iPods (or the iPhone), the Scosche PassPort HomeDock doesn't add any new features to your old products. For instance, you can get your old speaker dock to charge your iPhone, but unless it's been iPhone-certified, you'll still get a warning message on the phone and a prompt to switch it into airplane mode for music playback. Because the Scosche PassPort Dock cannot add shielding to your old speaker dock, you should expect to see this message. Similarly, the video output capabilities on older docks (DLO HomeDock Deluxe, Bexy iMirror) still won't work with the iPhone or iPod models made after 2006.
Overall, the value of the Scosche PassPort HomeDock is proportional to the amount of money invested in the iPod accessory you're trying to adapt. In many cases, the cure may be worse than the ailment. The PassPort's $39 price tag and the eyesore of its raised plug design may not be worthwhile for adapting your $80 iPod alarm clock, but it's a relatively painless fix for bringing your $300 first-generation Bose SoundDock up-to-date. However, in future versions of the PassPort Dock, we'd like to see a more low-profile design.
If you're looking for something similar that will adapt your in-car iPod-compatible stereo for the iPhone or recent iPods, be sure to check out the original Scosche PassPort.