Available at www.getcellranger.com for $129, the device has an external antenna and a 15-foot cable.
The Sony and RCA models are equipped to use an external antenna.
Some of those issues can be addressed with a $300 optional external antenna, but that adds more bulk.
The feature will also connect to an external antenna claimed to increase signal strength by one or two extra bars.
(You can also use Wi-Fire, an external antenna from hField Technologies that increases the signal strength).
Because of the way the device rebroadcasts the signal, the external antenna must be about five feet away from the base station.
But they do issue one caveat: in some situations, like airplane travel, the unit will function better with an external antenna.
The receiver, which sells for $99 and is available at www.plextor.com, has an external antenna and software that scans for over-the-air HD signals.
Once the connection to the external antenna is made, though, listeners may catch strong radio signals coming from all over Asia.
Incoming calls mute the car's audio system, and an external antenna improves signal strength and reduces the problem of dropped calls.
When it launched, a furore erupted suggesting the external antenna made it was hard to make calls if you held it wrong.
