
CS-SRM Short Range Modem Package
The CS-SRM short range modem package is used for direct communication between a
Campbell Scientific datalogger and a computer over distances up to 12km (depending on
baud rate and wire gauge). The package consists of:-
2 off RAD-SRM Asynchronous Short Range Modems
1 off RAD-SP In-line Surge Protector
1 off RAD-SP Station Surge Protector
1 off SC932C Compact RS232 Interface
1 off 9-Pin to 25-Pin Cable.
The standard RAD-SRM ensures integrity of data transmission using unconditioned 4-wire
links at data rates of up to 19,200 baud. The CS-SRM is supplied specifically to connect the
CS I/O part of a Campbell Scientific Datalogger to a RS232 COM port on a PC. The use of
USB-RS232 converters may be possible, if power to the RAD-SRM modem is on continually.
For other connection requirements, please contact Campbell Scientific for advice.
RAD
RAD
SRM-5A
SRM-5A
U L
R
THIS EQUIPMENT COMPLIES WITH THE REQUIREMENTS IN
PART IS OF FCC RULES FOR A CLASS A COMPUTING DEVICE.
E109091
LISTED
46D2
NW
GQ
U L
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1. Description
The CS-SRM can operate without an external supply, the small amount of current
required being drawn from the RS232 circuits. A switch-selectable DCE/DTE
option allows the RAD-SRM modem to operate as a DTE-type device for
connection to another piece of DCE equipment without the need for a cross-over
cable (see Figure 2).
The RAD-SRM has transformer coupling between itself and the 4-wire cable
which, in conjunction with electronic circuitry, protects it from AC or DC
overvoltages up to 1500V RMS and provides isolation for the two ends of the link.
The standard modem is not BABT approved and should therefore not be used in
the UK on leased lines. Please contact Campbell Scientific if you require a BABT
approved modem.
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