300Mbps Wireless N USB 2.0 Adapter: TRENDnet TEW-624UB Review

According to the manufacturer, this 300Mbps Wireless N USB 2.0 Adapter seamlessly connects to your wireless network without performance degradation. But is it really so? Let’s find out from our review of this USB adapter supporting 802.11n draft standard.

by Platon Scheblykin
02/26/2008 | 10:43 AM

A new wireless adapter from TRENDnet is going to be the main hero of this review.


The TEW-624UB is a USB adapter supporting Draft N standard. The manufacturer’s website says it supports the first version of the standard although the second version is the most recent one.

Anyway, we’ll test the TEW-624UB and see what it is capable of in real applications.


Specification and Accessories




Wireless standard

- IEEE 802.11b/g
- IEEE 802.11n (draft 1.0)

Encoding standard

- WEP (64/128bit)
- WPA2


- 2 internal antennas

Signal modulation

- 802.11b: CCK (11 and 5.5Mbps), DQPSK (2Mbps), DBPSK (1Mbps)
- 802.11g: OFDM with BPSK, QPSK and 16/64-QAM sub-Carrier modulations
- 801.11n: OFDM, 64-QAM

Operating frequency

- 2.412 - 2.484 GHz

Nominal data 
transfer rate

- 802.11n (draft): up to 300Mbps
- 802.11g: 6, 9, 12, 18, 24, 36, 48, 54Mbps
- 802.11b: 1, 2, 5.5, 11Mbps

Operating channels

11 for North America, 14 Japan,
13 Europe (ETSI), 3 (non-overlapping)


USB 2.0, 1.1 Standard

Other interfaces



From the USB port


During reception: 260mA
During transmission: 420mA


80(L)  x 27(W) x 12(H) mm

Additional features


The box contains:

Design and Functionality

The design of the new wireless adapter from TRENDnet has not gone far from the previous models of such adapters from the same firm. It is in fact the same except for some minor details. The device has a large blue case with straight outline. It looks like an enlarged copy of some flash drive.

There is a small detail near the place where the case meets the protective cap of the USB connector. It looks like some button, but actually it is an indicator of the adapter’s activity. It is black and opaque when inactive. It shines in orange when the adapter is turned on and blinking when the adapter is exchanging data.

Another special feature of the TEW-624UB is that it has vent holes in the sides of the case. This USB adapter gets rather hot at work, so these holes are quite appropriate here.

You can carry the device in your pocket or hang it on your neck. There is a special hole in the case for a neck strap but you have to find the strap separately as it is not included into the kit.

Now that we’ve looked at the TEW-624UB from each side, it’s time to see what’s inside it. Its case can be parted in two along the surrounding seam by means of a knife or something:

The adapter’s PCB is fixed in the case with plastic holders and can be easily taken out of the open case. It has an ordinary size for such class of devices. The component mounting is dense, yet clever and neat. There are elements on both face and reverse sides of the PCB.

The LED of the adapter’s indicator is placed rather far from the opening in the case, and its light is transferred there via a rather long light pipe.

It’s not quite clear where the third antenna mentioned in the specs is. As you can see in photos, there are only two antennas here.


The adapter is based on Marvell’s TopDog chipset consisting of an 88W8362 MAC-controller and an 88W8060 RF-modulator. The latter is covered with a metallic screen.

Bundled Software

An important thing for every wireless adapter (and for other device types as well) is the driver and accompanying software. The latest driver I could find at the TRENDnet website is dated December 2006, which means that the adapter indeed offers support for the first version of Draft N only. I used this driver for my tests.

There is a special tool that replaces Windows Zero Configuration for the TEW-624UB. This tool, called TEW-624UB Manager, appears in the System Tray when you connect the adapter to your PC. The Manager performs such typical functions as showing information about the current connection, searching for access points, establishing a connection, etc. There are five tabs in the Manager window where you can do something or just view adapter-related info. The tabs are in the left part of the program window while the contents of each tab are displayed in the main part of the window.

The Link Info page provides basic information about the current wireless communication session: session SSID, channel number, frequency, encryption, etc. The two graphs on this page, updated in real-time mode, show the data reception and transmission speeds. Although the graphs are not very precise, this feature is a nice addition to the rest of the information provided on the page.

The Configuration page shows those settings of the adapter that are going to be useful if the adapter is used in ad-hoc mode.

The Advanced page offers traffic encryption options.

The Site Survey page displays a list of access points that have been found after scanning through the entire operating frequency range. A list of all connection profiles defined manually by the user or created automatically on the first connection to an access point is shown here, too. The list and the profiles are editable.

On the last page, About, you can find information about the driver and utility and look up the adapter’s MAC address.

Summing everything up, the TEW-624UB seems to have average functionality. Besides the real-time speed graphs, the manager doesn’t offer anything exceptional to you. It doesn’t have serious flaws either, though.


The TEW-624UB is the first and only device based on the TopDog chipset we’ve ever dealt with at our labs, so I cannot test it together with a router based on the same chipset. Anyway, you’ll see how Marvell’s chipset works with chipsets from other manufacturers: I’ll test the TEW-624UB with routers based on chipsets from Atheros, Broadcom and Ralink. These routers have already been tested in our labs, and we know their capabilities well enough. And we’ll check out the TEW-624UB with a router based on the Marvell chipset as soon as we have such an opportunity.

I used the following hardware and software for the tests:

First I tested the speed of router-adapter (LAN-WLAN) and adapter-router (WLAN-LAN) connections using the High_Performance_Throughput scenario of the IxChariot program. The connection was established near the routers with WPA2-PSK encryption using the EAS algorithm. This is the standard encryption for Draft N, and it is going to be such in the official 802.11n specification.

The results do not leave a very nice impression because the TEW-624UB has problems communicating with other manufactures’ chipsets, especially with the Atheros chipset (in the Linksys WRT300N router).

Next I measured the WLAN coverage area using almost all possible combinations of routers and wireless adapters. I measured the signal level of a LAN-WLAN connection in five points:

Point 1: Near the router
Point 2: At a distance of 4 meters without obstacles
Point 3: At a distance of 5 meters + two thin gypsum wallboards
Point 4: At a distance of 6 meters + one brick wall, about 30cm thick
Point 5: At a distance of 17 meters + one thin gypsum wallboard and one 50cm brick wall

The TEW-624UB doesn’t do well in this test, either. Among the chipsets included into this review, it works best with the Intensify chipset (ASUS WL-500W). The most surprising thing in this test was the increase of speed when I moved from the second to the third point with the Edimax router. This effect was repeatable.

So, the difference between the first and second versions of the Draft N standard may be conspicuous sometimes as you could see in today’s tests. Of course, the TEW-624UB might have done better if tested together with a TopDog-based router, yet it would hardly have showed a really high speed then, either.


Summing up this short review, we cannot recommedn TEW-624UB adapter from TRENDnet for use with devices based on different chipsets. This USB adapter is rather stable with the Broadcom chipset, but the speed parameters are not quite good even then. I wouldn’t expect it to run at high speed even if the adapter is used together with devices based on the same chipset (TopDog), particularly because the TEW-624UB has only two antennas.