Well I bought a US PS Vita (Locked to AT&T) knowing that I couldn't use it with another data provider. Well here (in my country) there's no AT&T so the first thing I did was: remove the SIM card of a 3G Modem, then put it on the PS Vita.. (With the false hope that magically worked)
This picture is with the AT&T SIM card

This picture is with my 3G Modem SIM

Well the message with any SIM but AT&T was "Invalid SIM" so I thought: "and.. if I put one of these "turbo sim" things?" (I googled it but didn't find someone that tested it)
So I bought this: hxxp://www.focalprice.com/MX192X/Univer ... _Card.html (the cheapest one that I found and that seems like a good one..)
So I inserted the 3G Modem SIM (with the "turbosim") and it worked, it shows that is registered with the local carrier (ENTEL) with 3G connection:

(If you look closely there's the AT&T data connection activity on the live area)
But there's a catch.. when I tried to open a web page using the browser the first time it told me that I need an "AT&T data access plan or something like that" so I pressed the button "get a plan (I don't remember the exact text)" and it opened the "AT&T data provider" activity (actually is a web page).. well inside there appeared a red text that tells "INVALID SIM" I clicked the link "Privacy policy" (just to test something) and then the X to close the web page, and then appeared a message that says "You need to wait a few minutes to start using the data connection (I don't remember the exact text)" I closed the activity, and went back to the web browser, this time I entered http://www.google.com in the address bar and it started loading the page.. well after like 10 second it showed me the "C4-3619-9" error.
Well, i didn't had another SIM to test, searching on google I found that some data providers don't work with the PS Vita (even the "legal" unlocked ones), so It'll be interesting if someone can test other data providers using the same method.
PD:
- I had to cut a little bit my 3G Sim to use it with the "turbosim" so be warned.
- Sorry for my english (not my native language)
- Thanks to all the people that makes this community so great.
This is a picture of all of the ingredients used:

Hope this help someone and thank you for reading!









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