Nifty little gizmo powers gadgets from audio jacks!

[NatCh]

Does music really charge you up? Now music can charge up your gear!

I ran across this little dilly in the Continental Airlines in-flight magazine (hey, I have to do something during the take-off/landing electronics moratorium ). An outfit called Inflight Power has developed a little do-hickey to charge up batteries from any audio jack.

Their target application is obviously charging things on airplanes, but the principle should work with anything that has an audio jack: boom-boxes, televisions, even your computer or those cheap clock-radios hotels tend to like to provide.

How does it work? Well in their words:

Simply by plugging in the cable to the passenger seat headset jack, the cable converts the audio output into regulated USB power. Our new version adds an optional battery BOOST to increase the power supplied and offer continuous power.

So, reading between the lines, this thing takes an audio output signal (which is just low-power AC when you come right down to it) and converts it to USB grade DC to charge up whatever you plug into it.

It does seem a bit pricey, starting at $35 with no adapters (and of course they have bundles), but not all that pricey.

I can't find any size specs on it, but it looks like it's a bit bigger than four AA batteries would be.

It caught my attention, partly because it's just such a clever notion, but also because I can see it as a good potential solution to lots of travel-charging needs, particularly when traveling abroad: less need to worry about adapters when anything with an audio jack will do.

What do y'all think? Dandy Do-dad? Or a solution in search of a problem?

[solitarywolf]

I don't know about this. If you read between the lines in their FAQ page I get the feeling that this is "snake oil". I love the louder the songs, the faster the charge FAQ. Not to mention they recommend the installed battery version over the "radio/headphone charge.

Here is a copy from their site:

Frequently Asked Questions

Does the cable charge my device continuously?

With the optional battery boost feature, the device will output power continuously, in the non-battery boost mode the Inflight Power cable uses an internal trickle charger that takes 3-5 min to fully charge, then outputs power to the attached device (phone, music player etc). It does this repeatedly; batterires are recommended for better perfomance.

Does the charger work better with certain seat music channels or audio selections?

The Inflight Power cable works well on loud forms of audio (Marachi), music channles do better than talk channels, and be sure the volume is adjusted to maximum. Not all audio channels will provide sufficient power. Ask your flight attendant if they provide a "Charging Tone" audio channel, this is a saturated audio recording provided by Inflight Power to the airlines to ensure good performance.

Can I plug-in and use the cable before takeoff and after landing?

Yes, the Inflight Power cable is FCC certified and does not emit radio noise. You can use it anytime. Note: some flights do not turn on the seat audio system or reset the volume of the audio after take-off; so for optimal performance check the audio levels after take-off to ensure they are set to maximum.

Can I plug-in to other audio sources to get a charge?

Yes, the Inflight Power cable can operate using battery power and no audio input, or can operate on headset output signal from a laptop, an iPod or other audio source.

How do I know the Inflight Power Cable is working?

A led/light within the cable's plastic case will glow when the cable is ready to charge the attached device.

CABLE TEST PROCEDURE - To test the device with no battery boost
You can test the product using just an IPOD,
1) simply download our power tone Right Click to download Power Tone Clip
2) download this file to your IPOD, using ITunes etc.
3) select Setting>Repeat = One from the main IPOD menu, this will loop or repeat the song played.
4) plug the Inflight Power Cable audio plug into the IPOD’s headset jack.
5) select Music>Songs>500HzPowerTone from the song list, play this song (really a tone not a song)
6) after 90 seconds of playing the power tone above, the Inflight Power Cable LED light will glow and you can plug the USB IPOD attachment into the IPOD bottom connector or plug-in a Blackberry USB cable and charge.
Can I use the USB cable that is included with my mobile device?
You can if the USB cable is a charging cable, this can be determined by plugging the USB cable into a PC or laptop USB port (computer turned on), and attaching the associated mobile device. If the mobile device indicates that it is charging then the cable can be used with the Inflight Power cable. Note: some USB cables require software drivers to operate and require the attached device to first sync before allowing the cable to be used for charging, these will likely not work with the Inflight Power cable. See our product section to purchase a charging USB cable or tip for best results. Not all USB devices can charge using the Inflight Power cable, see the products section for more information on tested devices.

-Seth Williams
San Francisco, CA

[NatCh]

It's actually a (pardon the pun) sound electronic principle. An audio signal is essentially an AC electrical signal. The louder it is, the greater its amplitude. The more sound there is a signal (by that I mean sound to silence ratio), the more electricity is coming out of the signal.

Based on my recollections of my electronics classes, this is probably a very refined rectifier and voltage regulator set up. Nothing special, just a clever application.

The added batteries would "fill in" the silent bits of the audio signal, so yeah, it would definitely work better with them.

I expect that at its root, this is like one of those battery operated "boost your cell phone" things that are becoming ubiquitous, but with the added twist of being able to also draw power from an outside power source: an audio jack.

[arit]

Yay, neverending source of power for our eBook readers with mp3 support. They found it, the perpetual motion!

At least it is not ugly, and you might be able to charge devices a bit in trains e.g. when no real power source is near.

[DaleDe]

Originally Posted by arit

Yay, neverending source of power for our eBook readers with mp3 support. They found it, the perpetual motion!

At least it is not ugly, and you might be able to charge devices a bit in trains e.g. when no real power source is near.

Hey you could use your iPOD to charge your eBook Reader

Dale

[Nightwing]

Yes it will generate voltage.. But catch is how much current... I saw this a while back and the catch was output current...

Assume they added the battery since its a weak source of power without it.

Take the RMS of that "AC" signal and you can see why its good on paper but not in practices. Its probably a simple Full bridge rectifier AC to DC with some type of regulator possible a non switching one...

[DaleDe]

Originally Posted by Nightwing

Yes it will generate voltage.. But catch is how much current... I saw this a while back and the catch was output current...

Assume they added the battery since its a weak source of power without it.

Take the RMS of that "AC" signal and you can see why its good on paper but not in practices. Its probably a simple Full bridge rectifier AC to DC with some type of regulator possible a non switching one...

Probably from the description they store up energy in a capacitor and then charge the device momentarily then recharge the capacitor. If you read between the words in the description that it what they are saying. It would take forever to actually charge anything this way.

Dale

[Nightwing]

Originally Posted by DaleDe

Probably from the description they store up energy in a capacitor and then charge the device momentarily then recharge the capacitor. If you read between the words in the description that it what they are saying. It would take forever to actually charge anything this way.

Dale

Yep.. Its a charge then dump.... Interesting on paper but odds are not in the wild.

[grimo1re]

Right. Any volunteers willing to blow 35 bucks on this & review it?