We've been getting a lot of questions about how a new wireless USB adapter from a company called Gsky stacks up to the Alfa AWUS036H 500mw USB adapter that we sell (we ran a head to head test which we will discuss further down, but if you want to get right to the test results, click here).
The Gsky adapter looks a lot like the Alfa model, it also boasts the same maximum output of 500mw. We went ahead and got one of the Gsky adapters online, after all if there is an adapter out there that can perform as well as the much heralded Alfa long range adapter, it is certainly something we would want to inventory.
The first thing we noticed when we hooked it up and looked at some of the documentation was that claims on some web sites that it is a clone of the Alfa AWUS036H 500 mw adapter are not true. The Alfa adapter has a Realtek 8187L chipset, while the Gsky has the 8187B chipset, also from Realtek but with lower receive sensitivity. We should note for Linux users that the Alfa 500mw adapter is plug and play in Backtrack 3, while the Gsky with the 8187b chipset is not- it was not recognized by Backtrack 3. We also found out that with the Gsky you can only transmit at high output when using 802.11b throughput or lower. If you want to have an 802.11g connection (54 mbps), the output drops to just 30mw (yes, that's thirty, not 300).
The biggest difference though was the actual receive sensitivity. Here is a look at what you get with the Alfa (the numbers recorded are negative, so in this case the lower the better, as such, -90 means greater sensitivity than -80):
11 mbps -91 dBm at 8% packet size
54 mbps -76 dBm at 10%
Here are the numbers for the Gsky:
11 mbps -82 dBm at 8%
54 mbps -65 dBm at 10%
Seems like a pretty big difference, especially at the 802.11g/54 mbps level.
Okay, but numbers aren't everything, so we decided to pit both adapters head to head using an indentical 8 dBi antenna to see how the above differences manifested in actual usage. The adapters were positioned in the same place, one after the other, with the same 8 dBi antenna connected to each one. The tests were run 2 minutes apart. For comparison purposes, we also tested the Alfa 50mw (fifty mw) AWUS036E model. We have put the results into this PDF file here.
The final conclusion?
Alfa 500mw AWUS036H- detected 16 APs, 3.2/5 bars average signal strength
Gsky 500mw- detected 9 APs, 1.5/5 bars average signal strength
Alfa 50mw AWUS036E- detected 8 APs, 2.9/5 bars average signal strength
As the test demonstrates, the Alfa 500mw adapter gets the best range, and the best signal strength compared to the Gsky. The Gsky gets a slightly better range than the AWUS036E model from Alfa, which we have priced at $24.97 at the time of this blog post. But the AWUS036E model is more sensitive.