Vswr Alarm Troubleshooting; Data Conflicts And Data Loops; Led Status Indicator - Raymarine AIS700 Installation Instructions Manual

• Using a non-wideband VHF antenna optimized only for VHF radio frequencies may cause
transmissions from the AIS transceiver to be reflected back into the AIS700, due to the poor
impedance match of the antenna and AIS transceiver frequencies. Although this will not damage
the AIS700 (because AIS class B transmissions are of substantially lower power than VHF
transmissions), it could result in the AIS700 triggering a system VSWR alarm.
• New VHF antennas are sold with a fixed cable length. The cable length partly determines the
antenna performance, and therefore cutting the cable of an antenna can affect its performance
and result in a high VSWR ratio and limited reception.
Recommended specifications for a VHF antenna suitable for connecting to the AIS unit:
Frequency band
VSWR (Voltage Standing Wave Ratio)
Impedance
Gain
Connector type

6.3 VSWR Alarm troubleshooting

If you experience regular VSWR alarms try the troubleshooting guidance below.
Possible causes
Incorrect antenna in use.
Antenna short or open circuit.
Product running an older version of software

6.4 Data conflicts and data loops

To avoid potential data conflicts and data loops, products should not be connected to the same
device using more than one network protocol.
Important:
• Do NOT connect to an MFD or VHF radio using NMEA 0183 and SeaTalkng ® / NMEA 2000
connections at the same time.
• Do NOT connect to a PC using NMEA 0183 and USB connections at the same time.
• If you are connecting to a VHF Radio that has built-in AIS, you must first disable the VHF Radio's
AIS function, before connecting it to the AIS unit (or the same data network). Refer to your
Radio's documentation for details on disabling the VHF Radio's AIS function.

6.5 LED Status indicator

The LED status indicator on the transceiver provides an indication of product status.
LED Color
Green
Amber
48
156.025 MHz to 162.025 MHz
should not exceed 2:1, across the entire
frequency range
50 Ohm wideband
3dBi Max
PL-259
Possible solutions
Check that your antenna meets the required
VHF antenna specification that can be found in
the product documentation.
Check antenna for short or open circuit, repair
or replace as necessary.
Software version 1.09 included Improvements to
Antenna fault detection (VSWR alarm).
Status
Transceiver is powered up and operating normally.
Transceiver is not transmitting.
• Wait at least 30 minutes to check that a 'Quiet time' has
not been requested by the local authority.