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Glenayre Western Multiplex Lynx.sc
Glenayre Western Multiplex (GWM) developed the original spread-spectrum T1 product, which it first delivered in 1992. Its third-generation offering, the Lynx.sc, performed well during our tests. Although it would be easy to point to its DIP switches as evidence of a dated design, this is the kind of product that, once set up, is likely to run unaltered for years. Units are delivered from the factory preconfigured for specific radio channel-pairs, so the Lynx.sc was very easy to install. We didn't need to adjust a single DIP switch. Still, a lack of software configuration tools makes it impossible to change parameters on a remote unit without physically visiting the site.

Lynx.sc's newest features include a service channel to carry alarm and management traffic without affecting T1 performance; an order-wire interface to allow intercom capabilities between units; and remote monitoring via front-panel controls. Unlike P-Com AirPro's order-wire capabilities, which ring all telephones on a network, Lynx.sc's can be addressed individually.

We tested GWM's single-channel 5.8-GHz offering, but the vendor also offers dual-T1 products at 2.4 and 5.8 GHz, as well as a four-channel product at 5.8 GHz. Unlike Adtran and Wave Wireless, which offer modular units that separate the modem from the RF unit, all the GWM products use a single-unit design. GWM asserts that the use of low-loss cable at 5.8 GHz results in only minimal performance advantage for modular unit designs. And because Lynx.sc has the best receive sensitivity of any unit we tested, GWM can afford to sacrifice a few dBs by sticking with a single-unit design.

Although all the vendors agreed that the vast majority of installations are within 20 miles of each other, Lynx.sc supports a maximum transmission range of 50 miles, the most of any product we tested. If you're like me, you probably attribute this bravado to marketing specsmanship, but GWM claims to have several hundred sites operating at distances greater than 50 miles apart.

GWM's management strategy is based on the TBOS (telemetry byte oriented serial) management standard developed by Bellcore and AT&T. GWM's OpenLynx is a Win32 application that communicates with the Lynx unit via a serial connection. At a hub site, multiple Lynx radios can be interconnected and monitored by daisy-chaining the diagnostic and auxdata ports. OpenLynx is essentially a monitoring tool that allows a technician to view configuration, performance and alarm parameters from up to eight radios.

Lynx.sc, $7,495, Glenayre Western Multiplex, (408) 542-5200; fax (408) 542-5300. www.wirelessinterconnect.com