Liberty
Radio Extender System User’s Installation Guide 5
STEP 1: A RADIO COVERAGE SITE SURVEY ....................................................
THIS WILL REQUIRE 2 PEOPLE AND 2 CHARGED RADIOS.
BEFORE permanently installing the antenna for the LibertyRepeater we recommend that you do a “radio
coverage site survey” to insure optimal radio range and coverage
PREPARING FOR THE RADIO COVERAGE SITE SURVEY:
1. Charge the radio batteries for at least 12 hours.
2. When charged, make sure both radios are set to Channel 2.
Note: Since the antenna and the Libertyrepeater are not yet installed, you will need to use channel 2 of
the portable radios to communicate. Channel 2 is programmed for direct radio-to-radio
communication, NOT through the repeater.
CONDUCTING THE RADIO COVERAGE SITE SURVEY:
Every application is different, and therefore, no “single” rule applies when it comes to where to install the
antenna for optimal coverage. In general, the antenna for the LibertyRepeater is the “pivot” point for all
communication for radios operating on channel 1. You will need to try to optimize the location of the Liberty
antenna in order to reduce obstructions and the distance the radio signal must travel in order to get from any
point in the desired coverage area to the Libertyantenna. We recommend that you start by first attempting
to install the Liberty ANTENNA (NOT the repeater) “in the center” of the desired coverage area, this reduces
the distance the radio signal must travel by ½. If you’re attempting to cover a high rise building (e.g. 15
floors), go to a location half way up (e.g. 7th floor), and in the center of the building. As noted below, you may
have to try several locations before finding the best location for the Liberty antenna.
3. Person #1 will take one portable radio and go to the location you would “most likely” install the antenna for
the LibertyRepeater (see FIG-1 and FIG-2). This person will “simulate” the type of coverage you can
expect, IF, the antenna for the repeater were installed in this location. If necessary, position this person on a
ladder to more accurately mimic the height you intend to mount the antenna.
BE ADVISED – you may have to try several heights and/or locations before settling on the location
you like best.
4. While person #1 remains stationary, person #2 will take the second radio and “walk the site”. While “walking
the site” you must attempt to maintain radio contact periodically with person #1. This survey process will
reveal whether or not radio coverage is acceptable IF you install the antenna at the person #1 location.
Generally speaking, coverage will be slightly better when the repeater and the included antenna are
permanently installed.
If coverage is inadequate, Person #1 will need to relocate to a new location and repeat the process until
range and coverage are optimized.
5. For sites where coverage is desired in multiple buildings, such as an office complex, external mounting of the
antenna may be required. Before considering an external installation of the antenna, a site survey should be
attempted with person #1 positioned inside a centrally located building at the highest possible elevation (see
FIG-3). Person #2 will “walk the site”, communicating with person #1 from inside all buildings and at all
outside areas where radio coverage is desired.
CONSIDERATIONS:
•Don’t forget that the antenna cable is only 10 ft. long. You will need to run power to and mount the Liberty
repeater within at least 10 ft. of the antenna location you select.
•Typically, the higher the antenna the better but, NOT always.
•Every site is different. Thick, reinforced concrete, steel walls and vertical fire panels in ceilings can work to
block the penetration of radio signals creating dead spots.
•You may want to gradually lower the height of the antenna and/or its location and repeat your site survey to
see if coverage improves.
•It is best to only change one variable at a time e.g. antenna height or location, then repeat the survey process
and compare results.
