Product Reviews

Although USB (universal serial bus) has been a reality for the past three years, uptake hasn't been as fast as initially expected. However, USB devices are now finally appearing with increasing frequency and the majority of higher end monitors are also coming equipped with built-in USB hubs. With a well-established range of Gold Card PC Cards, Psion Dacom is now making a strong move into the USB market with the introduction of three new products. The Gold Port range consists of an external four-port hub along with a 10BaseT Ethernet adaptor and ISDN TA (terminal adaptor).

The Gold Port hub is a compact, palm-sized unit with one downstream and four upstream USB ports at the rear. It's a full-speed hub that supports connections over 12Mbits/sec and the slower rate of 1.5Mbits/sec. It comes with an external power supply but this is only required if the devices you're using need more power than the PC's USB port can supply. Most USB keyboards or mice, for example, run at 1.5Mbits/sec and can be powered directly from the host PC, whereas the Psion ISDN TA and Ethernet adaptor are both 12Mbits/sec devices that draw enough juice to require the transformer to be connected. However, the hub has a useful LED display on the front panel, confirming that each port is receiving power, and also has another row that shows whether a device is attempting to draw more power than the host PC can supply. For greater expansion you can daisy chain up to five hubs together, but these will all be using high-speed connections so each hub will require its own power source.

Hub installation is simple enough as you just plug the unit into a spare USB port, and Windows 98 does the rest. No drivers need to be loaded and the hub appears in the Device Manager as a general-purpose USB hub. Windows 95 users need not apply as none of the Psion USB products support this operating system. The Gold Port hub already supports Windows 2000 and Psion has assured us

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that drivers for the other products will be available on its Web site by the time you read this.

Installing the Gold Port Ethernet adaptor is straightforward as the test PC automatically detected the USB device on connection and just required the drivers to be loaded from the supplied CD-ROM. There's plenty of help in the on-line documentation for setting up a network connection and some useful troubleshooting tips as well. The adaptor has a couple of LEDs on the top panel showing link status and activity, which are handy for diagnosing network-related problems. Due to USB port limitations, the fastest network connection is the basic 10Mbits/sec. There's no point in supporting full-duplex modes or 100BaseTX as speeds of 20Mbits/sec and 100Mbits/sec respectively are well beyond current USB capabilities.

For performance testing, Novell's PERFORM3 was used with the PC logged into a NetWare 5 server. This handy little DOS utility transmits different-sized packets from the server to the PC over the network and logs the maximum transfer rate achieved. The best figure reported was 6.2Mbits/sec - a reasonable performance although around 22 per cent slower than a good-quality PCI network card.

The Gold Port ISDN TA is around the same size as the hub and packs in some useful features as it supports ML-PPP (Multi-link point-to-point protocol) so both B-channels can be combined for a 128Kbits/sec pipeline. According to Psion's Web site, the Gold Port TA also supports the BACP (bandwidth allocation protocol), which allows it to add or remove the second B-channel as demand fluctuates, although we could find no reference to this feature in the documentation. Using our test rig at Pavilion Internet, performance was no surprise, with transfer rates very similar to the majority of TAs we've looked at before. Using channel bundling, five test files totalling 11Mb were retrieved from our dedicated FTP server in 808 seconds at an average speed of 112Kbits/sec. Psion also bundles RVS-COM Lite, which installs six virtual modems, allowing users to send and receive faxes, carry out Eurofile file transfers and, providing a suitable sound card is installed, make voice calls and receive voice mail over the ISDN line.

Overall, the Psion Gold Port USB products look good value. The weakest member of the team is the Ethernet adaptor, but the hub offers users a simple means of expansion without eating up valuable hardware resources, and the ISDN adaptor delivers good performance and comes with a comprehensive software bundle.