ESE ES-102, Руководство по эксплуатации и обслуживанию

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APPLICATION NOTES
Application Note 1
ESE has noticed that the manufacturers' cable length specifications for the Motorola GPS Receiver and the Raven
LA-12F differ from the test results of ESE. Please be aware that Motorola specs the maximum cable distance
between the antenna and the receiver is 16’ 5” (5 meters) without amplification. Also, please be aware that Raven
specs the maximum RG-58 cable that the LA-12F can drive is 50 feet.
ESE's test results may indicate that longer lengths of cable may be used. We are not inferring that the longer cable
lengths should be used. We are only reporting the results of our tests and repeat the caution mentioned earlier.
Caution is recommended:
as the GPS Satellites age, their signal strength may decrease and excessive cable length may cause undesirable
results.
Application Note 2
All ESE tests were conducted using RG-58 coax cable. According to several manufacturers of low loss cable, the
signal loss attributable to cable length can be reduced with the use of "low loss" cable. According to the RG-8 and
RG-213 cable specifications, when compared to RG-58, cable lengths may be doubled or more with "equal to" or
"better than" results.
Application Note 3
Once an ES-102 has "Locked-on", the receiver creates a semi-permanent "Library" of where it expects to "see" a
satellite(s) at a specific point in time. However, if after "Locking-on", the unit is relocated (for instance, from the ESE
factory in California to an end-user's site in Europe), the unit's 1 PPS (and other outputs') accuracy may appear erratic
for up to three hours. When the receiver has created an updated Library, all outputs will then comply with the
specifications discussed in this manual.