HP an 1288-2 free download

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Configuring the HP 4396B for O/E Testing Application Note 1288-2 Introduction The recent trend in cable television (CATV) is the need for more selections, or channels, and the possibility of having interactive TV services such as On-Line-Banking and Movies-on-Demand. These requirements are pushing the limits of the copper cabling already laid out for today's CATV systems and these systems are not able to provide the "500 channels" of TV for the future. The industry is now changing from copper cable to fiber optic cable to carry the signals to the consumer. The fiber optic cable carries the channel information as light signals, but all major TV equipment works upon electrical signals. Hence, tomorrow's CATV systems needs both electrical-to-optical converters (E/O) and optical-to-electrical (O/E) converters. An O/E converter changes light signals to electrical signals, and an E/O converter does the reverse. These converters need to be tested for conversion flatness and efficiency. A converter with too much ripple can cause distortions in the TV channels audio or video signals, which will show on the TV screen. A converter with low efficiency, or gain, can lead to low signal-to-noise ratio, which would cause "snow" on the TV. A converter without flat group delay will affect the quality of the audio and color of the channel. There is a myriad of tests performed on these converters; this paper will concentrate solely on the test system setup for O/E converter test, using the HP 4396B 1.8 GHz Combination Analyzer. The HP 4396B The HP 4396B combines a network analyzer (NA), spectrum analyzer (SA), and impedance analyzer (ZA) into a single instrument. This combination allows for some major advantages: 1. Reduced capital equipment cost -- The HP 4396B costs less than a comparable network analyzer and spectrum analyzer if they were purchased separately. 2. Simplicity -- The HP 4396B is simpler to use. The front panel interface is always the same for every mode of the combination analyzer. Knowing how to operate the HP 4396B means you can operate 3 analyzers without constantly connecting and reconnecting the cables. 3. Accuracy -- The HP 4396B uses the latest digital signal processing (DSP) techniques to enhance its performance. The HP 4396B has digital