Comments

• srinath mallikarjunan August 8, 2012 at 2:06am

  Hi Alan

  If we just went by the difference in uplink and downlink frequency a 3G video call wouldn't be possible. Clearly the cell-phone tower does some stuff in between.(I guess compresses data and changes the frequency)
• Alan August 8, 2012 at 2:00am

  Hi Tommy

  Excellent find. I have just ordered the Pi but of course it is on back order!
• Alan August 8, 2012 at 1:53am

  As far as I can see it would not work as the Tx/Rx are on different frequencies. For example lets take the 1800 band – Uplink MHz 1,710.2-1,784.8       Downlink MHz 1,805.2-1,879.8.

  Your 3G dongles would transmit on the uplink frequency but can only receive on the Downlink frequency therefore dongle two cannot receive a signal from dongle one and vice versa.

  If it was possible you would be breaking the law.
• srinath mallikarjunan August 8, 2012 at 1:49am

  Let's assume the laptops were in 2 different cities. So you couldn't use a wireless lan/wifi.

  A conventional modem would enable point to point data transfer. Can a 3G modem also do this. In which case you should be able to transfer a file from 1 laptop to the other by dialing the sim card number of the other modem.
• 

  Tommy Larsen August 8, 2012 at 1:32am

  You can use a direct wifi connection between the 2 laptops without using the 3g modems. Setup VLC to stream between the laptops.
• srinath mallikarjunan August 8, 2012 at 1:07am

  Suppose you have 2 usb 3G modems, connected to 2 laptops. Can you exchange files/video between the 2 laptops without involving the internet.

  I know a 3G video call is possible between 2 phones, so i guess it should be possible to stream video from 1 laptop and view it on another. The reason i would like to avoid the internet layer is that it seems unnecessary. We just need reliable point to point communication/data links for a uav
• 

  Tommy Larsen August 7, 2012 at 10:30pm

  I think maybe we can find the solution on this link

  http://www.drupaler.co.uk/blog/installing-3g-usb-modems-linux/497
• Alan August 7, 2012 at 3:19pm

  Will

  It may be the Sim Card slot is not functioning but that is not important. Yes they connect to a computer but that is what the Rasberry Pi is. I agree that if you are using Windows then you use the included software, however I see no reason why software cannot be written for the Rasberry Pi computer to access the Dongle as it uses a simple USB interface.
• 

  Will Snodgrass August 7, 2012 at 1:02pm

  I have one of these USB dongles from verizon (3g CDMA) although it does have a sim card slot....but I always thought they just converted a gsm board an it was not functional. 

  Either way I believe it uses your computer (and the included software) to operate....
• Alan August 7, 2012 at 6:13am

  Hi Tommy

  Good work you are halfway there. I was going to put the scope on the dongle but it is probably easier to use a terminal program in the Pi.

  I am about to order a Pi but with a bit of luck you will have it sorted before mine arrives.