jotron TR-910, Руководство оператора и инструкция по установке, Страница: 37 / 48

4.4 Installa Ɵ on of TR-910
4.4.8 Antenna connec on
The antenna should be of good quality with regards to gain and VSWR to obtain maximum performance.
Make sure that the VSWR on the antenna is low, and that the cable from the transmi er to the antenna is
of good quality to avoid mismatch and unnecessary losses. A cable loss of 1 dB is the same as reducing the
power output of a 10 W transmi er to less than 8.5 W. Similarly, a cable loss of 2 dB is the same as reducing
the output power to less than 7 W. In areas were thunderstorms and lightning are a problem, surge arrestors
should be mounted between the antenna connector and the antenna cable. The arrestors should be good
quality and be capable of handling the output power of the transmi er. The antenna input of the transceiver
is the BNC-type antenna connector on the back of the transceiver unit.
Electrical Safety Earthing:
In case of installa on to external antenna, the antenna ground terminal must
be permanently connected/veri
fi ed with protec ve earthing conductor to
the building earth by a skilled person.
4.4.9 DC supply connec on
If the unit is to be installed in a vehicle, the included fuse kit (103079) in the vehicle variant accessory kit shall
be installed on the posi ve supply wire nearest the vehicle ba ery.
4.4.10 LAN connec on
If the unit is to be connected to a local area network, this can be done by connec ng a standard RJ45 patch
cable from the LAN connector to the network switch or router. Using LAN enables remote monitoring by the
Jotron RCMS system, remote VoIP recording and remote control with VoIP according to ED137.
4.4.11 I/O connec on
Connect to the I/O connector preferably with the radio turned o ff .
The following remote signals are available on the rear I/O connector:
• External speaker (Pin 1 & 2) output line pair is for connec ng an external speaker. This speaker output
has a dedicated ampli fi er and the volume can be regulated independently from the internal speaker.
Note: Ensure that the external speaker signals are not short circuit to ground or to each other.
• Monitor output (Pin 3) is an analog monitor output, 600
Ω
single ended and referenced to ground, pin
8. This output can for instance be used for connec ng an analog recorder. It will contain the received
audio when receiving and the demodulated transmi ed signal when transmi ng.
• TxKey / GPIO (Pin 4) is used to force the transmi er into low power. This is o en used o ff shore to force
the unit into low power during gas alarm condi ons. This pin can also be con fi gured to have other
func ons, e.g. Tx key input.
• Ba ery communica on interface (Pin 5) is the communica on line between TR-910 and the BU-872
ba ery pack. TR-910 uses this interface to read the ba ery status from the ba ery unit and present this
with a ba ery indicator on the front panel.
Doc. No.: 103614 TR-910 Operator Rev. AB
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