Listen Technologies LR-500 - Manual (Page 36)

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Channel Selection
It is important to choose channels that are free from interference to
achieve proper operation of your Listen equipment. This process is trial
and error. Before turning on the transmitter, listen to the wide band
channels on the receivers (channels 1-6). Listen to the audio through
the headphone or via the speaker and choose a channel with the
least amount of interference. Unless you are interfacing with an
existing narrowband transmission system, always use a wide band
channel.
If you are using multiple channels follow this process:
1.
Same Space:
If you are using multiple transmitters in the same space,
the most number of channels that will work simultaneously is six at
150 MHz. With all of the transmitters off, listen for interference on
all the wide band channels via the headphone jack on a Listen
receiver. Using the frequency chart on page 35, eliminate any
channels that have noticeable interference. Now choose the
channels with the widest channel spacing. It is
recommended that adjacent channels be spaced at least 300kHz.
2.
Distributed Spacing:
If you are using transmitters that are spread out
over space, you can achieve more simultaneous broadcast
channels. However, it is critical that your receiver(s) be located as
close to its transmitter as possible. You can use adjacent
channels (see frequency chart on page 35) in this case as long as
the adjacent channel transmitter is at least 50% further away from
the receiver as its transmitter.
It is highly recommended that after channel selection has been
achieved, you lock the channel so that it cannot be changed by the
user. To accomplish LOCK on the LT-800, press the “UP” button for 3
seconds. Repeat the process to unlock.
Wide Band Recommendation
Listen recommends that you always
use a wide band channel unless you
need to be compatible with existing
narrow band receivers from other
manufacturers. Wide band channels
have lower noise than their narrow
band counterparts.
150 MHz
The LT-800-150 MHz operates on 6
wide band channels and 26 narrow
band channels.
• 1 - 6 = Wide Band Channels
• 7 - 32 = Narrow Band Channels