"An audio jack provides no power." http://web.eecs.umich.edu/~prabal/pubs/papers/kuo10hijack.pdf http://web.eecs.umich.edu/~prabal/pubs/papers/kuo10hijack.pd..

"An audio jack provides no power." http://web.eecs.umich.edu/~prabal/pubs/papers/kuo10hijack.pdf http://web.eecs.umich.edu/~prabal/pubs/papers/kuo10hijack.pd... Really? It seems it's inarguably a crappy power supply but these people were able to extract over ten mW continuously from an iPhone 3GS's headphone jack, more than enough to run i.e. a commodity RFID chip.