GPS PC-board 6038
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Elektronik
version 03.01
page 7
3.2 Coaxial Cable Installation
The antenna is connected to the base device by means of a coaxial cable included in the deliv-
ery. The cable is connected to the antenna with a coaxial coupling at the plate foot of the an-
tenna. This coupling can be disconnected for cable laying purposes. Loosen the screw at the
antenna foot plate and lift the antenna plate (see drawing in the appendix).
Please note :
Do not lay the cable next to other HF-, control- or power cables.
The leakage from these cables could disturb the reception because of the very small reception
power.
The cable is connected to the clock device at the BNC connector of the unit. The standard
length of the antenna cable is max. 25 m (
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special cable up to 70 m). If the cable is longer
(up to 150 m) a GPS power amplifier must be looped into the antenna cable.
Please note :
Utmost care is required when laying the antenna cable.
Please make sure that :
•
the bending diameter must not be less than 10 cm in any place
•
the casing of the cable must not be damaged
•
the cable must not be crimped
Previously mounted BNC connectors are also a problem. Please do not remove the protection
until the cable has been laid.
3.3 Reception Frequencies
The satellites broadcast two frequencies:
L1 at 1.575,42 MHz
and
L2 at 1.227,60 MHz
The frequency L1 has been assigned for civil use.
The received power is about -160 dB. The antenna contains a pre-amplifier which boosts the re-
ceived satellite frequency by +20 dB.
