Unlocked Cell Phone HELP NEEDED!

[koolmoecraig]

So I took the fat pay check that I received from iFilm and treated myself to a Sony Ericsson K790A phone.  Details can be seen here:

http://reviews.cnet.com/Sony_Ericsson_K790a/4505-6454_7-31762056.html

Anyway, when I go to get service on the phone(Cingular or T-Mobile), do I have to commit to a contract?  Can I just do month to month since I'm not getting their free phone?  If I do have to be on contract and they give me one of those free phones, can I sell it on Ebay as "unlocked"?  Also, I'm not grasping the whole SIM card thing.

Any help would be appreciated.  The phone is just so badass that I dove in without figuring out the details.

Thanks!

[NightGod]

Yes, No (unless you want to pay per minute, rather than getting a monthly minute plan), Yes

SIM card is what "locks" the phone (and what connects you to the service provider). It's a little plastic memory chip that goes into your phone (usually underneath the battery). Until the SIM card is put in the phone, it's unlocked and can be used on any network. Once you put the SIM card in, the phone can't be switched to a different network (phone number can be changed by the provider)-there are ways to unlock some phones, but it's a twitchy process and doen't always work, sometimes it ends up frying the phone.

[shardian]

Yes, No (unless you want to pay per minute, rather than getting a monthly minute plan), Yes

SIM card is what "locks" the phone (and what connects you to the service provider). It's a little plastic memory chip that goes into your phone (usually underneath the battery). Until the SIM card is put in the phone, it's unlocked and can be used on any network. Once you put the SIM card in, the phone can't be switched to a different network (phone number can be changed by the provider)-there are ways to unlock some phones, but it's a twitchy process and doen't always work, sometimes it ends up frying the phone.

I understood that the phones were locked by the phone manufacturer on a per order basis for the provider.
Nokia phones are super easy to unlock. Other phones...not so easy. I was given an LG phone from a friend, and I had to send it off to get it unlocked.

[Lewis Black]

SIM card is what "locks" the phone (and what connects you to the service provider).

I am a pretty experienced Motorola cellphone tinkerer ('hacker' is a bit strong to describe myself) and this is actually untrue, the phone is locked in the firmware.   That is why 'unlocked phones' go for more than carrier-locked ones on ebay. 

A quick search at http://www.howardforums.com/forumdisplay.php?f=37 will get you all you need to know.

[Lewis Black]

[ChadTower]

My wife fully and thoroughly bought the "must hack it" mentality back in about 1998 when it turned a 35 DirecTV subscription into a 1000 channel DirecTV subscription.   

[shardian]

My wife thoroughly bought into the hack it/diy mentality........it's the time I have to invest that is the problem.
 

[ChadTower]

I don't even have that issue... if I'm working on something in the basement I'm not out drinking or screwing around.  That's a positive thing.

[shardian]

I don't even have that issue... if I'm working on something in the basement I'm not out drinking or screwing around.  That's a positive thing.

Well, we all wish you would hide out in the basement too, so I see where she is coming from. 

[shmokes]

Yeah, I thought the sim card is just your identity and phone number, etc.  My understanding is that if you and your wife both have unlocked phones, you can switch the sim cards back and forth as often as you like.  The phones don't become locked, they just take on the personality of whatever sim card is in it and only for as long as the sim card is in it.

I could be wrong, but why would people spend an arm and a leg for an unlocked phone if it had to be locked before they ever used it anyway.  May as well just buy it locked to begin with and spend half as much money.

[shardian]

Yeah, I thought the sim card is just your identity and phone number, etc.  My understanding is that if you and your wife both have unlocked phones, you can switch the sim cards back and forth as often as you like.  The phones don't become locked, they just take on the personality of whatever sim card is in it and only for as long as the sim card is in it.

I could be wrong, but why would people spend an arm and a leg for an unlocked phone if it had to be locked before they ever used it anyway.  May as well just buy it locked to begin with and spend half as much money.

I have an unlocked back-up, and I can swap out the sim card to each at will. The sim card holds all of the provider info and your account info.

[vader]

I work for TMobile, Cingular....and various other providers.

Sim Card = subscriber information and phone book
Phone     = if locked by the factory, you must unlock before using on any other system
                  it was not intended for

Unlocked Phone =  put your sim card in and ride, some features such as mobile web
                              or wap access may not work until phone is configured properly

Most phone can be unlocked, but it is a tricky process and can disable the phone

[ChadTower]

My wife lost the charger to her cell phone.  We haven't found a replacement yet.  That annoys me.

[koolmoecraig]

So Vader, I do need to purchase a plan though right?  It'll just be married to my sim card and not my phone?

[Lewis Black]

I'll respond to that... That is correct.