How to Make a Backpack Wifi Hotspot
• Junxion Box wireless gateway $700; junxionbox.com
• Verizon Wireless EV-DO PCMCIA card $100; verizonwireless.com
• Voltaic Systems solar-charging backpack $230; voltaicsystems.com
• 12-volt battery with spade terminals, 1.2 or higher amp-hour $15
• Male DC power plug, size M $5
• 18-gauge wire, black and red $5
• Female insulated quick-disconnect connectors, crimp-type, sized for battery spade terminals $3
• In-line fuse holder $7
• 20-amp fuse 50 cents
1) Plug in your EV-DO card and set up the Junxion Box to automatically assign TCP/IP addresses using DHCP, and disable the authentication splash page.
2) To build the power-adapter cable, cut a length of red wire and a length of black. Strip one end of each wire and crimp a spade terminal connector onto each.
Strip the other end of the red wire, and solder it to one end of the fuse holder. Wrap the connection in electrical tape. Take apart the male DC power plug. Solder the end of the black wire to the negative terminal of the plug and the red wire to the positive. Wrap the exposed positive connection in electrical tape, and reassemble the power plug. Install a 20-amp fuse.
3) Connect the Junxion Box cigarette-lighter adapter to the backpack “power out” plug.
4) Connect the battery cable to the “battery” plug on the backpack’s charge controller.
5) Take a hike - you're ready to go.