| 摘要 |
Portable frame generator for digital communications from 2 Mbit/s up to 140 Mbit/s, consisting of a lightweight, compact case within which there is a bus card at the lower part of the chassis, on which, arranged vertically in side guides, are the following cards: inputs, outputs and frequency meter, 2 Mbit/s generators, MUX for 8 to 2 Mbit/s, MUX for 34 to 8 Mbit/s, MUX for 140 to 34 Mbit/s FAST, MUX for 140 to 34 Mbit/s FL, CPU, peripherals, front panel and secondary power supply; other cards exist which are not connected directly to the BUS but to any of the plug-in cards, such as a front-panel card and primary power-supply unit, all for the purpose of checking the operation of the high-capacity digital systems in their various hierarchies, by simulation of the complete high- speed signal, by means of a portable instrument according to the CCITT standards. <IMAGE>
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