Design Guide DesignDesign GuideGuide
Designing a System
5A Cross out the LT-82 transmitters
Cross out the
5B Determine how many radiators will be used
Determine how many radiators will be used on each radiator daisy chain by reviewing the room layout work- sheet. Cross out the unused radiators on the system layout worksheet.
5C Write in the coaxial RF cable lengths for each radiator
Write in the coaxial RF cable lengths for each radiator used in the spaces provided. Review your room layout worksheet for this information.
5D Draw a connecting line from the power supply output
Draw a connecting line from the power supply output of the
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5E Cross out the unused power supplies
Cross out the unused power supplies.
5F Write in the CAT-5 power supply cable lengths
Write in the
5G Determine the delay compensation for each radiator
Now determine the delay compensation for each radiator using the Delay Compensation Calculator located in the back of this design guide. The correct setting of the delay compensation is necessary only in systems where there is overlap in coverage between two or more radiators. Write the delay setting on the System
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1Distance of Furthest Radiator (DFR)
Determine which radiator is the furthest from the transmitter on one of the two daisy chains. Calculate the distance from the furthest radiator to the transmitter and record it in
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2Radiator Distance from Transmitter (RDT)
For each radiator, determine the overall distance from the transmitter to the radiator.
Record the value of each radiator in the RDT column. See example below.
3Cable Delay (CD)
Determine and record the propagation delay of the coaxial cable being used. For Listen coaxial cable the delay is 1.54 ns/ft or 5.05 ns/m. This information can be obtained from
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4Calculate the delay setting for each radiator
Now calculate the delay setting for each radiator using the Delay Compensation
Calculator. The calculator uses the following formula to determine the delay setting of
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Delay Setting = (DFR – RDT) x CD / 25
NOTE: If your calculations suggest a delay setting greater than nine, please contact Listen Technologies tech support for more information.
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