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- MINIMUM LINE TESTING REQUIREMENTS
-
- AS SET BY THE FCC
-
- Your local telephone company is required by the FCC to
- provide a minimum level of quality on the lines it maintains
- for your use. Many lines do not meet these standards, and so
- are a source of considerable noise in the transfer of data
- between computers. A noisy line can make it very difficult
- to upload or download messages and files to a BBS.
-
- If a sysop complains to the telephone company about line
- noise, there is usually only one option offered: line condi-
- tioning. This is an extra cost item that they would like to
- sell you. However, if their line to your computer meets the
- minimum standards, there is no reason you cannot have error
- free transfers at 2400 bps and, if an error correcting proto-
- col is used, reliable operation at 9600 bps is the norm.
-
- If the telephone company seems reluctant to test your line
- and assure that it meets the minimum requirements (and they
- will), request that they run the following tests and provide
- you with the results. Let them understand that if they do not
- comply, you will refer the matter to the FCC. They will NOT
- be happy!
-
- The following tests should be run:
-
- 1) Frequency sweep. 300 to 3000 Hz
-
- 2) Roll off. 500 - 2500 Hz, with -2 to +8 range,
- and request 300 - 3000 HZ, -3 to +12 range.
- 1000 Hz tone loss: -16, 1% in either direction
-
- 3) Signal to noise ratio. 24 Db level
-
- 4) White noise C, message Dbrnco
-
- 5) Envelope delay measurement.
-
- 6) Phase jitter. Not to exceed 10%
-
- 7) Impulse noise test. Minimum 15 minute count
-
- Don't worry if you do not understand what all these tests
- mean, the telephone company knows. These standards are all
- available from the FCC upon request. When the lines provided
- to you meet these minimums, you will experience reliable,
- accurate, and noise free data transfers.
-
-
- Lloyd Kautz
- 75340,3326
- ......... . ... ...-.... 1200 N81N