cbanning

I've got both a Thunderbolt and Charge, and want to try to root the Charge (looks easier and I just like the phone better). My question is "can I leave the sim card in the Thunderbolt while I try to root the Charge with the Odin? thing).

Kelmar

Yes. You can use ODIN without having an SD card in the phone.

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Typos or odd wording??? I blame Swype for the Swypo's!

In use: (1) Samsung Galaxy S4, (1) Nexus 4, (1) Nexus 7, (1) Galaxy Tab 10.1
Recently retired: (1)Nexus 4, (2) Droid Razr, (2) Droid Charge, (1) Samsung Epic 4G, (1) HTC Evo, (1) HTC Hero

cbanning

Then do I have to put it in before I install a rom?

Kelmar

Most of the ROMs have an ODIN version.

I misread your initial question, but the answer is still the same. You do not need an sd card nor SIM card in to ODIN the phone. In fact, it's advised that you remove your SIM card prior to using ODIN anyways.