mergedK tima 2P, Reference Manual

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A partially obstructed sky view might delay or even prevent the initial GPS fix
ATTENTION
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required to start operation of the master clock.
2.4.2 Antenna Mounting
The antenna has a threaded base that allows it to be mounted through any
hole with a 12 or 13 mm (
1
⁄
2
in) diameter. Maximal thickness of the mounting
base is 4 mm (
1
⁄
6
in).
There is a 50 cm (20 in) long antenna cable routed through the threaded base
with a BNC female connector at its end permanently attached to the antenna.
When mounting the antenna, pay attention that the weather seal is placed
ATTENTION
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close to the antenna base and that the lock washer is placed on the same side
as the nut.
2.4.3 Antenna Cables
The antenna has to be connected to the master clock by using a 50 Ω coaxial
cable with BNC male connectors at both ends.
The antenna cable should be routed through a conduit, shielded from rain
ATTENTION
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and/or solar radiation. The conduit should not be shared with any power ca-
bling.
Total cable attenuation should be less than 45 dB. If using mergedK supplied
cables, following maximum lengths can be achieved:
External Maximum
Cable Attenuation Diameter Length
RG 58 C/U 100 dB/100 m 5 mm 40 m
Aircell 5 39 dB/100 m 5 mm 100 m
Aircell 7 27 dB/100 m 7 mm 150 m
LMR-400 17 dB/100 m 10 mm 250 m
Contact mergedK on any of the addresses provided at the back cover of this
document to order cables cut to length or if you require help selecting an
antenna cable.
2.4.4 Surge Arrester
To avoid lightning damages to the master clock, a Gas Discharge Coaxial Surge
Arrester (SKU 90 02 05 6) should be installed at the building or cabinet en-
trance.
Mount the surge arrester using a ‘L’-shaped bracket (not included) and ground
ATTENTION
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it using a cable with a cross section of, at least, 6 mm 2 (10 AWG). Use the same
ground-point as the master clock to avoid ground-rise-potential damage.
Connect the surge arrester to the master clock using a 50 Ω coaxial cable with
BNC male connectors at both ends.
Contact mergedK at any of the addresses shown in the back cover of this doc-
ument if you need additional coaxial cables to connect the surge arrester to
the master clock.
2.5 Decommissioning and Disposal
There are no batteries inside of the tīma master clocks and all components
are ROHS compliant.
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tīma 2P/2R GPS Master Clocks Reference Manual