ESE ES-185U, Operation And Maintenance Manual, Page: 13 / 25

Page 11
11.0 ANTENNA CABLE TESTS & ALTERNATIVES
The antenna supplied with the ES-185U is designed to provide excellent reception under a variety of
conditions. The optimal location of the antenna is such that the antenna has a full view of the sky and is
mounted on a horizontal plane. However, the view of the sky may be through a window and the antenna may
be mounted indoors if the roof or upper floors do not shield the signal. Note: It is advised to test the Antenna at
the location where it is to be mounted prior to mounting (and drilling holes) to verify proper operation.
One of the main concerns when using a GPS receiver (Master Clock) is the distance between the antenna and
the receiver. The ES-185U Antenna is supplied with 16’ 5” of coax cable which can be connected directly to
the clock. If more cable is required an in-line amplifier may be necessary.
When extra cable is required, several options exist. The most simple and least expensive methods are
discussed below. It is, however, the ultimate responsibility of the end-user to decide which option will best
satisfy the specific situation. Please feel free to contact the ESE factory for assistance.
Also... please read section 12 which discusses the tests performed at ESE.
11.1 Method 1 (low loss cable)
Several types of "low loss" coax cable are available including RG-8 and RG-213. Using any of these
types of cable "may" allow up to 300' of additional cable to be added to the 16’ 5” supplied with the
antenna. Both RG-8 and RG-213 are expensive (relative to RG-58) and are cumbersome to work with
due to their larger diameter.
11.2 Method 2 (in-line amplifier)
The use of an in-line amplifier such as the LA-12F (manufactured by Raven and available from ESE) may
be more convenient than low loss cable. Installing one of these amps "may" allow up to 150' of RG-58 (or
300' of RG-8/RG-213) to be added to the 16’ 5” supplied. The LA-12FN has 'N' connectors which allow for
convenient interconnections with RG-8 and RG-213 cable. See Figure 11A.
11.3 Method 3 (in-line amplifiers with power divider)
Due to the power limitations of the ES-185U's receiver and antenna, only one in-line amplifier can be
used. However, if a power divider such as the ES-AB1A is used, up to five (5) in-line amplifiers may be
added. The more amplifiers used, the shorter the cable run between amps. See Figure 11B.
LA-12F
ES-185U
GPS Antenna
16’ 5” 150’ (RG-58)
Figure 11A. Antenna With LA-12F And 150' Of Extra Cable (RG-58)
LA-12FN LA-12FN LA-12FN
LA-12FN LA-12FN
ES-185U
ES-AB1A
GPS Antenna
16’ 5” 100’ 100’ 100’
100’ 100’ 2’
Figure 11B. Antenna With 5) LA-12FN And 500' Of Extra Cable (RG-8) With ES-AB1A