Harris Corp. has introduced the Harris VF-40, a new voice transport module for land mobile radio networks.
The VF-40 works with Harris Intraplex Access Server multiplexers for T1 or E1 network applications and with Intraplex NetXpress multiplexers for IP networks. Targeted at state and municipal safety agencies, the VF-40 includes features to improve the efficiency of multichannel land mobile radios and the interconnection of land mobile radio dispatch sites and transmission towers, the company said.
According to the company, one of the major improvements of the VF-40 over older technologies is that it enables unobtrusive sharing of radio channels among multiple user groups by passing Continuous Tone Coded Squelch System tones, or Private Line (PL) tones, ranging in frequency from 67Hz to 254Hz. These low-frequency tones are carried through the four-wire audio channel along with the voice signal.
Chuck Alexander, Intraplex products director at Harris Broadcast Communications, said: Because the VF-40 has been optimized for transmission of low-frequency tones, including PL, Digital Private Line, and other low-frequency signaling techniques, it provides seamless support for the entire range of low-frequency signaling applications. For example, the enhanced low-frequency response enables the distribution of PL tones from a single point to each transmitter site in simulcast mobile radio systems.
