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Table of Contents Preface ........................... 7 Description ........................7 Safety .......................... 7 Purpose of this Manual ....................7 Warranty ........................7 Important Safety Information .................... 8 Contact Details ......................9 How to Use this Manual ....................10 Chapter 1. TestWizard ....................13 Getting Started ......................
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Normal Working Range ................... 27 Time and Date ......................27 Product Information ....................28 Chapter 4. Testing a Cable ..................... 31 Connection ........................ 31 Cable Type ........................ 32 Testing ........................32 Auto TDR Mode ...................... 32 Automatic Event Detection ..................33 Manual TDR Mode ....................
At higher frequencies: = √ ⁄ With some re-arranging: 59.9Ω √ ≈ 2 √ Foam Dielectrics When working with “foam” dielectrics the proportion of “air” to “dielectric” determines the effective relative permittivity.
When then reflection is zero. When is less than then the co-efficient is = negative and with greater than then the co-efficient is positive. This is sometimes expressed as a percentage “loss”: Γ...
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Percentage Return Loss Some people like the simplicity of expressing the return loss as a percentage. When simply working with the reflection co-efficient in this way, rather than in decibel form allows for simpler “fault arithmetic” (adding up of reflections). The following table shows the calculated reflection co-efficient based upon the mismatch between source and load impedance.
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Decibel Return Loss Remember that when working in decibels, the “log” function returns an “indeterminate” result for zero. Therefore, where the impedances match, the “ERL” is a “big number”. Faults need repair when return loss is less than about 40 dB or so (you company’s threshold may differ). Adding event losses in decibels is tricky;...
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BLANK PAGE TV220E Instruction 30 January 2023...
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TV220E Instruction Manual USA Headquarters Tempo Communications Inc. 1390 Aspen Way, Vista, 92081 California USA +1 800 642 2155 e- support@tempocom.com EMEA Sales Office Tempo Europe Limited, Suite 8, Brecon House, William Brown Close, Cwmbran, NP44 3AB +44 1633 927 050 e-...