Astra GAMP-2000, Справочное руководство

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Step 3: Hardware connections
3.1. Introduction.
The NMEA 0183 v2.0 standard and later, use a differential signalling scheme, in order to
ensure better insulation from noise than previous versions that were using 'single-ended' or
RS232 signalling scheme, ie with a single cable for data and a ground terminal (GND).
Connect equipment type 'single ended' with the new equipment of the differential type, can
cause damage or malfunction, as the terminal NMEA - / B is forced to the ground with the
possible consequence of heating and damage to the power supply circuits.
To overcome this problem, since the market still exist many devices 'single-ended', the
GAMP-0183 has two opto-isolated inputs, fully compatible with RS232 signals.
3.2. Connecting to differential NMEA devices
If the device is fully compliant to the NMEA 0183 standard, then simply connect the output
terminals
A/+ and B/- of the talker to the input terminals ( +) and ( -) of GAMP-0183.
3.3. Connecting to a single ended NMEA device
If the talker uses a 'single-ended' signally scheme (in the case of some antennas GPS, AIS systems or
personal computer), you must use the inputs NMEA NMEA In 2 and In 3 of GAMP-0183, connecting
the data
Tx to the input terminal ( +) , and the GND terminal to the input terminal ( -) .
Talker
Talker
GAMP0183
GAMP0183
Out B/-
Out A/+
Tx/Out
In +
In -
GND
In +
In -