Xylem H-4400 - Manual (Page 6)

1-4 RS-232 Data Radio
H-4400
1.4 Troubleshooting
The radios can be difficult to field test when operating with a data logger due to the intermittent
short bursts of data. The radio system can be more throughly tested with the aid of a lap-top
computer or RS-232 terminal. With the following setup you can transmit ASCII messages or
other test data while adjusting or aligning the antennas. The radio link is tested by connecting a
computer terminal to one radio and connecting a loopback connector to the other. With this
setup, one person can test both up-link and down-link communication paths.
The radios have a standard RS-232C interface which operates at 9600 baud. With a straight-thru
9-pin RS-232 cable, connect one of the radios to a laptop computer or terminal. The radios have
a female DB9 connector, pin-2 is received data output and pin-3 is transmit data input. The other
radio in the link to be tested must be setup for loopback operation. Do this by installing a
loopback test connector or connecting a jumper between pins 2 & 3. Set the power control
jumpers of both radios for “Always On”.
The wireless link is best tested with a test program provided by the radio manufacturer. The test
program “X-CTU” can be downloaded from the www.maxstream.net website. X-CTU
automatically tests the wireless link and provides a success/fail display of each data packet. Make
sure your computer is set for full-duplex, 9600 Baud.
Alternatively, you can use a terminal program such as XTALK or PROCOMM to test the radio
link. Make sure your computer or terminal is set for full-duplex, 9600 Baud. Test the radio link by
typing characters and checking for the proper echoed response. As you type, the characters are
transmitted to the remote station then re-transmitted back to the local station and displayed on
your screen. Both up-link and down-link paths are tested at the same time.