I recently published a series of articles entitled How to Build a Long-Range Wi-Fi System that attracted quite a bit of interest. The series starts at http://rv.dickeastman.com/2012/01/how-to-build-a-long-range-wi-fi-system-part-1.html.
I used a 2.4 GHz High Power Wireless Outdoor CPE Model TH-WA5210G manufactured by TP-Link mounted on a flagpole that attaches to the ladder on my motor home. It connects to any wi-fi "hot spot" within a quarter mile or so and often to hot spots much further away.
I know from comments posted here that several people purchased an identical 2.4 GHz High Power Wireless Outdoor CPE Model TH-WA5210G or TL-WA5210G but had difficulty configuring it and asked me questions about it. To be honest, I did all this about a year ago and encountered little difficulty. I did not experiment with all the available options. It installed within a minute or two and today I couldn't remember enough of the details to answer many questions. I decided to take new screen shots of each significant step in the set-up process and post them here for others to see. Perhaps that will answer most of the questions.
First of all, I would strongly suggest you download the users manual as a PDF file as recommended in the small brochure that came with the router.
I noticed that TP-Link apparently has updated their devices since I purchased mine. My unit is a model TH-WA5210G, according to the label on the back of the unit. However, all I see online now is the model TL-WA5210G (notice the letter "H" has been replaced by an "L.") You want to obtain the online manual that applies to the device you purchased. I believe one manual covers all the devices but you might run into small differences.
The support page for the TL-WA5210G is available at http://www.tp-link.com/en/products/details/?model=TL-WA5210G while the users manual may be downloaded from the same page (click on "DOWNLOAD").
The manual has excellent step-by-step instructions for set-up as well as detailed instructions on the various options available. In case of a conflict between the manual and my screenshots, I'd suggest believing the manual. I am not certain that the way I set up my device is the BEST way, it is simply one way that worked for me. Also, there might be a slight difference amongst optimum settings between the TH-WA5210G and the TL-WA5210G.
First of all, if you plan to use a wi-fi router in addition to the TP-Link TH-WA5210G/TL-WA5210G, leave it in the box for now. You will need it later after you have configured the TH-WA5210G/TL-WA5210G.
For simplicity's sake, I will refer to the TP-Link unit as the TL-WA5210G instead of listing both model numbers. However, to my knowledge, these instructions should apply to both models.
Plug an ethernet cable into the TL-WA5210G's connector and the other end of the cable into the POE (power over ethernet) box that was included with the TL-WA5210G. Connect a second ethernet cable from the POE box to your computer. Next, plug in the power adapter for the POE box to a power outlet and wait a minute or two for the TP-Link unit to power on, boot up, and be ready for configuration.
Set the ethernet (not wi-fi) networking software in your computer to TCP/IP.
NOTE: You can revert back to the old settings after the set-up is completed.
The exact instructions will vary from Windows to Macintosh to Linux. However, a quick Google search should find lots of instructions for the version of the operating system software you are using. In all cases, set the computer to the following:
Set up the TCP/IP Protocol for your computer. Configure the network parameters for fixed I.P. addresses, not for DHCP. The IP address is 192.168.1.xxx ("xxx" is from 1 to 253), I used 192.168.1.22 but that last digit could be anything from 1 to 253 as long as that address is not used by something else on your network). Set the Subnet Mask to 255.255.255.0, and the Gateway address to 192.168.1.254 (The AP's default IP address.)
If you are using Windows, reboot the computer. A Mac will not need a reboot and I am not sure about Linux.
Once the TP-Link router is powered on and plugged in to your computer's ethernet port, launch a web browser. Any web browser will do, I used Chrome. Then tell the web browser to go to http://192.168.1.254 (that is the address of the TP-Link device and you should memorize it or write it down or highlight it in the users manual). You will see a log-in screen, if your device is properly connected to the computer and is powered on and your computer's networking software is properly configured.
When asked, enter a user name of "admin" (without the quotes) and a password of "admin" (without the quotes). You can then change that user name and/or password for security purposes. Click OK or press Enter of your keyboard, and the management page will display.
You will then see this:
(Click on any screenshot to see a larger and more readable image.)
NOTE: This is a screenshot of my TP-Link device AFTER it was configured and shows what you need to get to. Your screen might look slightly different before it is set up.
Click on NEXT.
Select AP (meaning "Access Point.") I think this is the part that confused many people. In my network with a separate wi-fi router, Access Point is the appropriate choice. If you are using a different network configuration, you might need to select something else although I am not sure what is best for your configuration. All I can do is suggest reading the manual.
Click on NEXT.
The SSID shown is the default entry and you can change it to anything you want. To change it, enter a string of up to 32 characters with no spaces or punctuation. The same Name (SSID) must be assigned to all wireless devices in your network. The default SSID is set to be TP-LINK_XXXXXX (XXXXXX indicates the last unique six characters of each device's MAC address), which can ensure your wireless network security. But it is strongly recommended that you change your networks name (SSID) to a different value. This value is case-sensitive. For example, TEST is NOT the same as test.
Select the country where you are located. This is important for legal reasons because different countries use different channels (frequencies) for wi-fi. You don't want the authorities knocking on your door in a few days!
Click on NEXT.
You are (almost) done!
Click on FINISH.
Wait a minute or two for your TP-Link device to re-boot and come up in normal mode. Once that happens, you will see the following screen except for a few minor things:
The MAC address of your device will be different from what is shown above as every device has a unique MAC address. Your SSID may or may not be the same, depending upon what you specified earlier. The channel number might be different.
Now you need to specify the distant wireless network you wish to connect to and share. Select Wireless and then Wireless Mode.
Click on CLIENT and make sure the "radio button" has a dot in it, meaning the selection is active. Now, at the bottom of the screen, click on SURVEY and wait a few seconds. The TP-Link device will scan and find all the wi-fi channels within reach. Pay attention to the signal strength numbers shown, the higher the number the stronger the signal. You probably cannot maintain a reliable connection to a network with a weak signal (showing a low number, such as 30 or less).
Click on the network you wish to access and share. You will see that network's information pop into the appropriate spaces on the screen. Scroll to the bottom of the screen and click on SAVE.
OK, now you are really done!
Surf the web on your computer to make sure everything is working. Once you are happy with the results, unplug the ethernet cable from your computer and plug it into your wi-fi router. I used an Apple Airport Extreme.
Now you need to configure the second router to share the connection being sent over the ethernet cable from the TP-Link device to your wi-fi router. Exact instructions will vary from one model of wi-fi router to another. See your wi-fi router's manual for assistance. The instructions should be very similar to sharing a cable modem or DSL or FIOS Internet connection.
Once completed, you can now share the one TP-Link connection amongst all your Internet-enabled devices, including computers, iPod, iPad, Android tablet computers, "smartphones," Microsoft Surface, Wii, Nintendo, Apple TV, Roku, any other streaming television service, and more.