@sam 
The Huwawei E155X series of usb modems appear to support STK access.
There are plugins for Mobile Partner that allow to access to STK functionality on these.

My best guess is that the STK on the E155Xs are accessed either by a non standard AT command set or APIs provided by their drivers....tho i would place my money on the former.

Anyhow, a good Google search on these will tell you whether they are best suited to your mission.








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In programming, as in everything else, to be in error is to be reborn. 
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