Downgrade Baseband for yellowsn0w: 3G Fuzzyband Downgrader
by Nic Elder
May 11, 2009
Did you accidently upgrade your phone to 2.2.1, or worse 3.0 betas, without heading the advice to wait for an official dev-team release? Are you stuck with a phone that can't be unlocked using yellowsn0w now? For some of you there may now be a solution.
3G Fuzzyband Downgrader is now available in cydia on jailbroken phones. Fuzzyband will allow you to downgrade from any baseband (2.30.03 - 4.26.08 as of the time of this writing) back to 2.28.00 the official unlockable version.
Unfortunately this will only work on early adopters phones. It requires bootloader version 5.8 found only in phones sold the first couple of weeks that the 3G was released. If you are unsure of your bootloader version, just download Fuzzyband, install, and run, it will tell you your current version, and whether you can downgrade or not.
For those of you who might be going, "huh?" let me explain a little about what the baseband is, and why you would want to downgrade it.
The iPhone is actually 2 devices, a phone or modem, and a computer. The computer portion of the iPhone has an operating system (OS), the currently released version is 2.2.1, with 3.0 coming out in a few months. The phone/modem portion of the iPhone also has an operating system, the currently released version is 2.30.03, or 4.26.08 if you are using beta 5 of OS3.0.
When you buy your iPhone from the store it's locked to a carrier (AT&T in the United States where I reside). yellowsn0w was released by the dev-team to allow you to use the phone with any carrier (t-mobile, or overseas prepaid cards are an example). yellowsn0w currently only runs on modem version 2.28.00.
You may be saying "But Nic, I'm happy with my carrier, why would I want to unlock?", and I would tell you that in a few months when a new iPhone is released, you may want to sell yours, either on ebay or to a friend. A phone that can be used on any carrier is worth about double the amount of money that a phone locked to say AT&T is. A quick scan of ebay shows unlocked 3G iPhones selling for $500.00 to $700.00 (USD).
