mcmurdo Smartfind M10, User Manual

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74
6 TROUBLESHOOTING
The transmitting LED (Green colour) is not illuminated
The transmitting interval of a Class B transponder is 3 minutes if the speed
of the vessel is less than 2 knots. If the speed exceeds 2 knots, the
transmitting interval will be 30 seconds. For each transmission, the
Tx/Silent LED will flash Green once quickly. The Tx indication could be
missed if not observed carefully.

For unit to transmit it requires the GPS information from the GPS
antenna. Without the GPS information, the unit will not transmit an AIS
signal. Please check if your GPS antenna is connected and setup
correctly. See section 3.7 for further information.
Smartfind M10 receives AIS signals normally, but no
one in the surrounding can see me, why?

AIS Class B transmission range limitation: an AIS Class B transponder
transmitting range is 5-7 miles in perfect conditions. The AIS receiver in
the transponder will typically see Class A vessels that are 20-30 miles
away or more in good conditions. The reason for this is that all AIS
Class B transmit at 2 watts whereas the Class A transmit at 12.5. This
difference in transmission power impacts on the range of each
transponder type. For this reason, it is quite possible that Class A
vessels can be seen, but Class B vessels might not be seen.

VHF antenna interference: if you are using a dedicated AIS/VHF
antenna for your transponder, be sure that it is placed at least 6 ft (1.83