nwhitfield
Member

Registered: Feb 2000
Location: London, UK
Posts: 92 |
Frequency confusion
The FAQ for the VisorPhone states that
> with Visor Solo, Visor, or Visor Deluxe, it operates in a frequency band used only in North America.
which suggests it's using the 1900MHz frequency band. It implies that future Visor products may allow it to be used on other bands, and that there will be a separate version for the European/Asian market, where GSM is run on 900MHz and 1800MHz.
The Handspring newsletter that arrived in my mailbox says that if you buy the phone with a Prism or Platinum
> you'll be able to use your VisorPhone to make calls outside the U.S., too.
> In fact, you'll be able to roam in any country that has a GSM network.
Now, if that's true, then it means that the module must work on at least GSM 900MHz, which was the original GSM frequency band, and very probably on 1800MHz too.
So, what is it that's stopping the module from working on all those bands with a current Visor model? I really can't think of a logical explanation - it's just a frequency change, and surely all the RF circuitry is in the module. Maybe present Visor models are too susceptible to interference from GSM 900/1800?
Either the comment in the newletter is misleading - since you can't roam outside the US/Canada without a module that uses standard GSM frequencies - or there's something odd in VisorPhone.
Does anyone have any idea what's going on here?
Nigel.
|