Go to page of
A good user manual
The rules should oblige the seller to give the purchaser an operating instrucion of Polycom OMNIVS500, along with an item. The lack of an instruction or false information given to customer shall constitute grounds to apply for a complaint because of nonconformity of goods with the contract. In accordance with the law, a customer can receive an instruction in non-paper form; lately graphic and electronic forms of the manuals, as well as instructional videos have been majorly used. A necessary precondition for this is the unmistakable, legible character of an instruction.
What is an instruction?
The term originates from the Latin word „instructio”, which means organizing. Therefore, in an instruction of Polycom OMNIVS500 one could find a process description. An instruction's purpose is to teach, to ease the start-up and an item's use or performance of certain activities. An instruction is a compilation of information about an item/a service, it is a clue.
Unfortunately, only a few customers devote their time to read an instruction of Polycom OMNIVS500. A good user manual introduces us to a number of additional functionalities of the purchased item, and also helps us to avoid the formation of most of the defects.
What should a perfect user manual contain?
First and foremost, an user manual of Polycom OMNIVS500 should contain:
- informations concerning technical data of Polycom OMNIVS500
- name of the manufacturer and a year of construction of the Polycom OMNIVS500 item
- rules of operation, control and maintenance of the Polycom OMNIVS500 item
- safety signs and mark certificates which confirm compatibility with appropriate standards
Why don't we read the manuals?
Usually it results from the lack of time and certainty about functionalities of purchased items. Unfortunately, networking and start-up of Polycom OMNIVS500 alone are not enough. An instruction contains a number of clues concerning respective functionalities, safety rules, maintenance methods (what means should be used), eventual defects of Polycom OMNIVS500, and methods of problem resolution. Eventually, when one still can't find the answer to his problems, he will be directed to the Polycom service. Lately animated manuals and instructional videos are quite popular among customers. These kinds of user manuals are effective; they assure that a customer will familiarize himself with the whole material, and won't skip complicated, technical information of Polycom OMNIVS500.
Why one should read the manuals?
It is mostly in the manuals where we will find the details concerning construction and possibility of the Polycom OMNIVS500 item, and its use of respective accessory, as well as information concerning all the functions and facilities.
After a successful purchase of an item one should find a moment and get to know with every part of an instruction. Currently the manuals are carefully prearranged and translated, so they could be fully understood by its users. The manuals will serve as an informational aid.
Table of contents for the manual
-
Page 1
How to Choose an Acoustic Echo Canceller Application Note Polycom Installed Voice Business Group September 2004[...]
-
Page 2
Introduction Acoustic echo cancellers (AEC) greatly enhance the audio quality of a multipoint hands-free communications system. They allow conferences to progress more smoothly and naturally, keep the participants more comfortable, and prevent listener fati gue. An AEC solution that is poorly designed or inappropriate for the location will not prov[...]
-
Page 3
AEC Nonlinear Processing Mic Speaker Echoes Near speech Far speech Far speech Near speech + echoes + distortion Far End Near End XMT RCV Distortion Figure 1: Illustration of the effects of AEC operation and room acoustics on the transmitted speech. The far speech that trav els through the receive path is not modified as it passes through the AEC. I[...]
-
Page 4
frequently, if at all. With acoustic echo cancellation, the echo path is very complex (dozens or hundreds of reflections), lasts 100-200 ms, and can vary conti nuously during a conversation as people move around the room. Acoustic echo cancellers are therefore much more complicated devices. While line echo cancellers may have smaller price tags, th[...]
-
Page 5
Form Factor The form factor of the solution is very important because it determines how useful it is in an application. The performance of the product may not matter if its fo rm factor makes it inconvenient or impossible to use in the desired application. Of course, there can usua lly be some flexibility in choosing a form factor. Licensing an alg[...]
-
Page 6
Step 2: Eliminate the products that don’t meet G.167 or the tail length needs of the application. It is relatively easy to determine how well an AEC cancels echoes. Most AEC products are based on the same algorithm: the adaptive LMS digital filter. This is a very well-defined algorithm that has been used for years. Since this process is well esta[...]
-
Page 7
Room Acoustics G.167 testing is performed in real rooms. If the product meets the requirements in these rooms, it is compliant. A device that is G.167 compliant in one room, however, might not be compliant in another. This is because the acoustics of all rooms are different. This flexibility allows manufacturers to test their products in the types [...]
-
Page 8
The equation assumes that both the microphone and the speaker are mounted on the same wall (which is the worst case in terms of the number of reflections that will be cancelled). In that case, N must be an odd integer because the even reflections travel away from the microphone. For example, consider a 10x20x30 foot conference room wit h very refle[...]
-
Page 9
Step 3: Judge audio quality and state machine performance by comparative listening. Ideally, the AEC will let speech signals pass through it unharmed. This is actually the most difficult task in both designing and measuring the performance of an acoustic echo canceller. The real difficulty is in determining how the AEC sounds during double-talk, an[...]
-
Page 10
The two most critical states of the echo canceller are receive and double-talk. The receive state is the only opportunity for the echo canceller to converge correctly. It is also the time when the echoes are most noticeable because they are not masked by speech from the other side. During the receive state, the echo canceller must converge rapidly [...]
-
Page 11
acoustics have such a large impact. If this cannot be a rranged, at least consider the operating environment differences in each case in the final decision. If possible, listen to the room acoustics with the echo canceller disabled so the effects of the different rooms can be compared. Seven Things to Listen For • Residual Echo. If there is exces[...]
-
Page 12
A Short Glossary of AEC Related Terms Near end The end of the connection where the echo canceller is located. This is where the echoes take place. Also, see far end . Far end The end of the connection opposite the echo canceller. The user on this end could be using a handset or another hands-free system. This is where the performance of the echo ca[...]
-
Page 13
Technical Support For support on the Vortex product line, call toll-free (USA/Canada) 888-248-4143, then select option 1, then option 3. For exclusive Integrator and Consultant focused suppo rt (through our PASS program), dial 1.408.474.2048; this number will get you help on video and Vortex products. For general technical support, dial 1.800.POLYC[...]