You don't. The most likely result is fire and smoke. Most routers include a voltage regulator that will try absorb any over voltage on the DC input line. When it exceeds some voltage or dissipation level, the regulator will blow up. A wireless router is not a CB radio. I suggest you tinker with the antennas instead. The results tend to be less destructive and create less e-waste scrap.
How would you change to voltage of a wireless router to get more range.
From what I know, you need to fiddle with the transmission power through the routers configuration interface; however, chances are that the stock firmware doesn't allow the user to modify it, due to the risk of frying the router.
If you are using a Linksys WRT54G(S), then you could get a third-party firmware which exposes that functionality.
It can't be done.
Barry ===== Home page
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