Term
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Definition
A unit of information based on two symbols, states, or conditions. |
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Term
| What unit of measurement is normally used in data systems to express signaling speed for equipment? |
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Definition
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Term
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Definition
The unit of modulation rate of the shortest unit interval. |
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Term
| Briefly explain the difference between baud and bit. |
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Definition
Baud is an expression of time (duration) while bit carries no suggestion of time. |
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Term
| What is the difference between "overflow" and "underflow" in relation to bit count integrity? |
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Definition
| Overflow is when more bits are received than expected. Underflow is when fewer bits are received than expected. |
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Term
| What are the three terms we use to describe synchronization methods used in digital signaling? |
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Definition
(1) Synchronous (2) Asynchronous (3) Isochronous |
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Term
| How many synchronous pulses are needed in synchronous operation? |
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Definition
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Term
| Briefly explain the principle of synchronous operation. |
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Definition
In synchronous operation, the receiving device is adjusted automatically to the speed of the transmitting device by comparing the speed of the incoming signal with the time base of the receiving device. |
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Term
| What constitutes an asynchronous signal? |
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Definition
Any signal that contains sychronizing bits within its signal stream. |
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Term
| Briefly explain the principles of asynchronous operation. |
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Definition
In asynchronous operation, a receiving device is started with a start bit and runs only until it receives one character, then a stop bit causes it to stop and wait on the next start bit. |
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Term
| How does asynchronous synchronization affect transmission speed? |
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Definition
| It slows transmission speed. |
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Term
| What is an isochronous signal? |
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Definition
| A signal where all bits are of equal duration. |
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Term
| Of the synchronization terms synchronous, asynchronous, or isochronous, which is normally used with channel-packing systems to indicate the utilization of internal timing? |
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Definition
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Term
| Define the term "clocking." |
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Definition
| The term clocking means "the rate of running" or "to keep approximately standard time." |
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Term
| What is a station clock? What can a station clock minimize? |
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Definition
A station clock is a clock that controls some or all of the equipment in the station that require local time control. Using a station clock can minimize the effect of most of these impairments. |
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Term
| What are two types of station clocks? |
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Definition
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Term
| What is the master station clock? |
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Definition
The master staion clock is a highly stable cesium beam or GPS timing signal, and is going to be tied into the primary communications equipment. |
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Term
| How does a slave clock get its timing? |
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Definition
A "slave" clock locks onto an incoming data stream from a stable source. |
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Term
| How does synchronization distinguish positions in the data bit stream? |
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Definition
Since only 1s and 0s are transmitted, the equipment uses patterns of frame bits to distinguish positions to the data bit stream. These patterns we call framing formats. |
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Term
| Name two factors that determine when a digital transition should occur. |
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Definition
(1) The bit rate of the signal (2) Its format |
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Term
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Definition
| Information is contained in the level. One level is transmitted for a mark and another for a space. |
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Term
| What is a bipolar violation? |
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Definition
When two consecutive mark (1) signals occure with the same polarity. |
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Term
| How does the B8ZS signal format correct ones density problems? |
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Definition
By intentionally insterting BPVs into the signal to break up long strings of zeros. |
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Term
| What are the three types of communication signals that are the functions to control and process analog calls? |
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Definition
(1) Control Signals (2) Information Signals (3) Supervisory Signals |
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Term
| What are the two methods of address signaling? |
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Definition
(1) Pulse dialing (2) Tone dialing |
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Term
| Call waiting is what type of communication signal? |
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Definition
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Term
| What is the purpose of supervisory signaling? |
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Definition
Monitor the status of a line or circuit to determine its state. |
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Term
| What are the two signaling methods to transmit supervisory signaling? |
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Definition
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Term
| How does CAS signaling convey signaling information? |
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Definition
| This is known as bit robbing. |
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Term
| How does CCS convey signaling information? |
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Definition
It uses a separate network channel to transfer supervisory signaling information in an out-of-band fashion and multiplexed with the digitized voice signals. |
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Term
| What are the three CCS signaling modes? |
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Definition
(1) Associated mode (2) Nonassociated mode (3) Quasi-associated mode |
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