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When encountering a problem with a modem installation, follow these steps in
order. What follows is a list, starting with the most common, of problems
which are often encountered in modem installation.
14.1
Power
Check whether the PWR LED on the modem has turned on. Fully on indicates
the modem is powering up, flashing indicates successful network registration.
14.1.1
SW12
If using SW12 and the modem does not appear powered up, temporarily wire
the modem to the logger’s 12V terminal. If the modem then powers up, the
program in the datalogger used to control the SW12 port may be at fault.
14.1.2
SIM Card
The SIM card should be inserted into the modem as shown in section 6. Note
the picture above the SIM slot on the modem that indicates correct orientation
of the SIM card.
14.1.3
Antenna
Ensure that the antenna (and surge suppressor, if applicable) is connected to the
modem. Inspect cables and connections for damage or loose wires.
14.1.4
SC932A/SC105 Orientiation
When using the CS I/O kit, it is possible to connect the modem and logger to
the incorrect inputs on the device. Please check wiring against the figure 4.1 in
section 9.
14.1.5
Network Coverage
This can be easily tested if you have a mobile phone on the Telstra network. If
not, you can check using the LEDs on the modem as described in section 7.
For a more accuarate measurement of signal strength, this can be determined
by connecting to the modem with a terminal program (See section 7.2.1) and
sending AT+CSQ followed by the Enter key. The modem will return two
numbers in the form +CSQ: x,y where x is your signal strength (0-31, 31 is
best) and y is your bit error rate - you can normally disregard this second
number. If your signal strength is lower than 9, you may experience
disconnections and low data rates.
14.1.6
Baud Rate
The default for the modem is to communicate at 115200 to any device. For
some Campbell Scientific data loggers, such as the Array-Based data loggers,
the maximum baud rate is 9600. Please check the data logger manual for
maximum baud rate and program the modem accordingly.