Listen LR-600, Руководство пользователя

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Listen SQ
TM
& Coaxial Cable
18
We are accustomed to listening to low noise, high fidelity audio (delivered via CD,
DVD, etc.). FM radio systems, such as those made by Listen, have more inherent
noise compared to most sound systems. To reduce noise of our systems, Listen uses
a noise reduction technology called ListenSQ™. Both the transmitter and receiver
must have the SQ feature enabled to achieve the desired results. SQ is available
on new Listen systems, including the system you received in this shipment. If you
are planning to use this product with older Listen systems that do not have Listen
SQ or equipment not manufactured by Listen, you should disable Listen SQ.
Your Listen equipment has been shipped to you with the SQ feature enabled. You
may need to disable the SQ function for one or more of the following reasons:
1. You are using your new Listen system with older version Listen equipment that
does not have the SQ function.
2. You are using your new Listen system with equipment supplied by other manu-
facturers.
3. You expect that end users may bring and use their own receivers that don’t
have the SQ function.
Listen SQ™- Improving Your Listening Experience
SQ Summary
· Improves noise perform-
ance by at least 20dB
· SQ is NOT compatible
with older version Listen
products
· SQ is NOT compatible
with other manufacturers’
products
· SQ is NOT squelch
· To work properly, SQ
must be enabled for both
the transmitter and
receivers
· SQ can be disabled to per-
mit operation with older
Listen products or other
manufacturers’ products
The antenna for the LR-600 can be mounted directly on the unit if desired.
However, you may find that the unit will provide better performance when the
antenna is located elsewhere. If you plan to mount the antenna in a different loca-
tion than on the top of the unit, you must use cable and connectors rated at 50
Ohms. Although cable used for cable TV installations looks similar to this cable, it
won’t work with your Listen system.
If you need to run cable over a greater length than 50 feet for 216MHz applications
or greater than 100 feet for 72MHz applications, we recommend that you use RG-8
cable rather than RG-58. It is a lower loss cable, meaning that more of your signal
will reach the antenna.
Long cable runs can result in signal degradation due to “loss” characteristics of the
cable. At 72MHz, there is an average loss of 2dB per 100 feet of cable and at
216MHz an average* loss of 5 dB per 100 feet of cable. (A 3dB loss means half of
your power has been lost.) However, it is better to suffer coaxial power loss than to
try to shoot your signal through obstacles! Obstacles, especially metal, can create
drop-outs or reflections of your signal that will result in poor listening conditions.
*NOTE: There are many varieties of 50 Ohm, RG58 and RG8 cables. You may
purchase a cable that is better or worse than this value. Please check with the
cable vendor or manufacturer for exact specifications.
Coaxial Cable