Quick Take: Want to takeover the FM airwaves with your music? iTrip is the only way to do it.
A month or so ago I reviewed Belkin's TuneCase wireless FM trasmitter for iPod. A wireless FM transmitter plugs into the iPod's headphone jack and broadcasts the audio signal over a chosen FM frequency so you can enjoy the music (or whatever you listen to) through a nearby radio. Transmitters like this are a great idea if you want to listen to your iPod in the car -- while many new stereos have input jacks or CD players that can read .mp3 files, there's nothing quite so nice as being able to queue up your favorite iTunes playlists for the drive home from work.

Or so my car-owning friends tell me.

Well, while I am convinced that FM transmitters are a good idea, the Belkin TuneCast was not a very good product. It suffered from a weak broadcast signal and lack of frequency choices, both of which rendered it nearly useless in New York City, where the FM band is about as crowded a spectrum as you'll find anywhere.

The folks at Griffin Technology caught wind of my transmission troubles and sent one of their iTrip FM Transmitter for Ipods my way. If you're in the market for one of these gadgets, the iTrip is clearly the way to go.

The only real downside to the iTrip is that it's so well designed to fit your iPod that you can't use it with any other audio source. iTrip snaps into iPod's headphone and remote jacks, whereas the TuneCast has a standard mini-stereo plug on a cable, so you can use it with other audio sources (PowerBook, MiniDisc player, etc). Of course, the TuneCast doesn't broadcast very well, so it kind of doesn't matter.

Good Design, Easy to Use
That being said, iTrip is very well designed. The white cylindrical body matches iPod perfectly, and also draws power from the Pod, so you don't need to shell out even more money for batteries. If you keep your iPod plugged into your car's cigarette lighter while the iTrip is in use, you won't even notice the very minimal battery drain it causes.

Installing iTrip is a snap, and the included software (which also works with Windows) adds a new playlist to your iPod: Each of some 100 frequencies (from 88.1 - 107.9 on your FM dial) shows up as a song file. To choose a frequency, you just play the associated song and follow a little two-button tap routine as outlined in the directions. An LED on the iTrip blinks at you to confirm your new selection.

If you've never used an FM transmitter, you might be asking yourself, "Why is he writing about how to switch frequencies?" Good question. The trick with these things is finding some open space on the FM spectrum within which you can turn your iPod loose: iTrip is really cool, but a $30 transmitter is no match for a million-watt commercial radio transmitter. So you have to find an empty slot if you want to hear your iTunes, and in a crowded market like New York -- or if you're driving from market to market -- that means you'll have to switch frequencies sometimes.

Finding a good frequency inside of my Brooklyn apartment was a little tricky, but it could be done. Once I had the signal locked in, the sound was bright and clear, much like the iPod sounds when it's plugged in directly via RCA jacks. The listed frequency range of 50-15,000 Hz is narrower than the iPod's 20-20,000, but the actual difference will be lost on most people most of the time, all the more so if you're listening to compressed (mp3, AAC) files over a car system.

I brought iTrip on a car trip to the Poconos Mountains, and it peformed really well. We had to frequency-hop and point the unit directly at the car stereo within city limits, but once we got out over the bridge into Jersey, iTrip had a little more operating room and performed like a champ. I wondered if I could promote my band by taking over passing cars' radios with our songs. My driving companion calmly dissuaded me, citing a number of practical and ethical reasons...

At home I had to keep iTrip within 5 feet or so of my stereo, whereas once we were up in the mountains I could stretch out near the advertised broadcasting range of 30 feet. Again, the FM spectrum is packed to the hilt where I live (and I've got a whole lot of electronics gear in my tiny apartment, some of it better shielded than others, which may or may not affect iTrip's performance), so if you live/drive in a less crowded area you shouldn't have any problems. And I can't think of too many places more crowded than NYC, unless maybe you live in Tokyo or Hong Kong.

Conclusion: Take iTrip on yourTrip
My old roommate used to have a hand-me-down 1986 Honda Prelude that he let me drive sometimes. That car had a tape deck, and we had one of those fake-cassette adaptors with an 1/8" minijack plug so you could run a CD player through the car speakers. I used it with my iPod and it was great. Well, that car died and I get the feeling most people don't have tape decks in their cars anymore. Unless you do, Griffin's iTrip is probably the easiest way to play your iPod through your car stereo. It's well designed, easy to use, and works very well. At $30 or so, it's more expensive than an RCA patch cable, but a lot less than buying a new car stereo with RCA jacks. Recommended.