Search results
Results from the WOW.Com Content Network
The modular design also reduces the burden on the logistics system to provide repair parts. The SINCGARS can operate in either the single-channel (SC) or frequency hopping (FH) mode, and stores both SC frequencies and FH loadsets. The system is compatible with all current U.S. and allied VHF-frequency modulation (FM) radios in the SC, nonsecure ...
Several hand-held Project 25 radios used around the world. Project 25 (P25 or APCO-25) is a suite of standards for interoperable digital two-way radio products. P25 was developed by public safety professionals in North America and has gained acceptance for public safety, security, public service, and commercial applications worldwide. [1]
The predecessor to the No. 1 Crossbar was the panel system, which was used in many large metropolitan areas beginning in the early 1920s. By the 1930s, there was a growing need for a new type of switching machine that did not have the drawbacks inherent in the panel system. Desirable features of the crossbar system included: [3]
A trunked radio system is a two-way radio system that uses a control channel to automatically assign frequency channels to groups of user radios. In a traditional half-duplex land mobile radio system a group of users (a talkgroup ) with mobile and portable two-way radios communicate over a single shared radio channel, with one user at a time ...
The No. 4 Electronic Switching System (4ESS) is a class 4 telephone electronic switching system that was the first digital electronic toll switch introduced by Western Electric for long-distance switching. It was introduced in Chicago in January 1976, to replace the 4A crossbar switch. [1]
A more practical approach, and one adopted by the majority of WSS manufacturers is shown schematically in Figure 1 (to be uploaded). The various incoming channels of a common port are dispersed continuously onto a switching element which then directs and attenuates each of these channels independently to the N switch ports.
The Switching Control Center System was an operations support system developed by Bell Laboratories and deployed during the early 1970s. This computer system was first based on the PDP-11 product line from Digital Equipment Corporation and used the CB Unix operating system and custom application software and device drivers that were developed and maintained by Bell Labs in Columbus, Ohio USA.
Since the signal routing and signal conditioning needs of a test system differ from design to design, RF/Microwave Switch Matrices may be custom designed by the test system engineer or by a hired contractor for each new test system. The Switch Matrix is made up of discrete electronic components including RF switches and signal conditioners that ...