Case Study of a Cheap USB WiFi dongle for Noobs

[Jim JKla]

Case Study of a Cheap USB WiFi dongle (Once debugged it will end up in the Wiki) for Noobs

I bought a USB Wi-Fi Dynamode WL-700N-RXS 150Mbps Nano 802.11n Wireless USB Adapter Dongle for £5.95 I flashed a 4Gig Class 4 SD card with the Wheezy 2012-12-16 image. My router is a Netgear DG834G router running DHCP and I am using WPA-PSK+WPA2-PSK security with a decent Alpha Numeric password using upper and lowercase letters. My power supply for the RPi is a Belkin F5U010 USB Hub which has a 4Amp PSU the hub is set up to power the RPi and a USB back link to be the distributed USB for the RPi

I have done some surfing and have drawn a reasonable blank but I now have established a method for setting up this wireless dongle.

Ok first off I need to have the HDMI connected to a TV/Monitor in my case a TV.

I tried with composite connection but there is an issue with my TV is probably addressable by changing the screen resolution but that’s a separate issue.

As I said earlier a USB cable connects the output of the RPi to the Root port of the USB Hub. And one of the output ports connects to the Micro USB supplying the RPi with power.

The Dongle is plugged into one of the spare hub ports.

The keyboard is also connected to the hub.

However due to problems with the mouse freezing it is connected directly to the RPi.

OK I boot the RPi but make no changes when the raspi-config starts selecting finish.

Then use “startx” at the command prompt running the x window.

Double click the WiFi Config icon this should open the wpa_gui window click scan and this opens a Scan results window on the first attempt I did not see my router but clicking the Scan button on that window found the SSID of my router.

A double click on that line brought up A new window in the name of my of my Router.
The first box displayed the SSID Name
The second box displayed the Authentication Type
The third the Encryption Type
The fourth box was Blank this was where it was waiting for the router wireless password.

This is typed in blind well not completely blind it does asterisks the entry so you need to type carefully.

You then click the add button (on composite connection I was unable to scroll down to or even see this button) initially the first time I tried this I had no connection I removed the Nano dongle when I plugged it back in it connected and I had a popup telling me I was connected.

Then I logged out of the x window using the LXDE logout from the icon at the bottom left of the screen this returned me to the login command prompt.

Ok then the usual Login pi Password raspberry and “sudo halt” at the command prompt to achieve a clean shut down.

So I now unplugged everything this included the HDMI and removed the USB Nano dongle from the hub plugging it directly to the Lower RPi USB port (It does not really matter I only mention lower for completeness).

I now re-powered the RPi from my USB Hub so that the only physical connection to the RPi was the Micro USB supplying power.

I now went back to my PC and fired up my browser and connected to my router using the usual IP address 192.168.0.1 admin login and password (changed to protect the innocent) In the admin window for the router I clicked on Attached Devices and have found a new connection with an unknown device with the address 192.168.0.5

I log out of my router and close the browser.

I now fire up Putty (there’s better instruction on this in the Blind Login section for Noobs to be found in the wiki here

http://elinux.org/RPi_A_Method_for_ssh_blind_login

I carefully add 192.168.0.5 as the address in and remotely log into my raspberry once I have passed the obligatory first time warning.

I immediately use sudo halt and use Win32DiskImage to make a backup of this SD card (note at this point raspi-config has not been run and at present the image is still in it’s reduced size state.

Having made the first back up I now replace the SD card into the RPi and re-boot and use putty to re log in to my RPi and after logging in run “sudo raspi-config” only to have my street hit by a power interruption that lasts no more than a second but it’s enough to scramble the SD card fortunately all that was needed was a re image from the backup.

Note if you do reload from the image the new image is the pre raspi-config so you need to re-run raspi-config after raspi-config has been run and you have used the EXPAND-ROOTFS menu option to use all of the available SD card.

You can make an image post this process but it will be a lot larger note that your first reboot after activating EXPAND-ROOTFS will take significantly longer (note just for that first boot).

[Jim JKla]

In all likelyhood this WiFi device may well work out of the packet with no issues if you have no WiFi security on your Router.

However where I live it is reccomended that you password protect your WiFi connection.

This is just one method of doing the job and leaving your password in place.

[Jim JKla]

I have gotten this to work using a composite link to the screen.

The tab key moves you on one field at a time when you are on the screen to add in you pre shared password.

Go to the bottom field you can see (assumming you can't see the add button that IS at the bottom hit the tab key twice and then the space bar if it works then you have found the add button and should have your link.

Look I know it's not elegant but it gets your WiFi.

[cyrano]

Thanks, Jim. This was a badly needed write-up.

Now can we have stickies?

[Jim JKla]

I am going to start a discussion with the Mods to see if we can get an area for posts like my one and like those that deal with broken SD card holders.

An area where the only the mods can add things and by default they are stikies.

By default because if it was MOD only cotrolled that would be the case anyways and locked of course.

However this would be MASSIVLEY OFF TOPIC here if you started a seperate thread I would feel obliged to contribute but at this time I intend to persue this via PM.