Section 6. Troubleshooting
6-10
9.
If you don't see characters echoed on the screen then the problem could be with
the RAD modem or the computer's serial port. Unplug the RAD modem from
the back of the computer. The COM port will have either 9 or 25-pins. The
pins are in two rows, with one row having one more pin then the other.
Call the row with the most pins as the top row.
Pin 1 is on the top row on the far left side. Pins are counted from left to right
across the top row.
Get into TERM and go into terminal emulations. Briefly touch the outer metal
shield around the pins to discharge any static electricity in your body. Take a
small screwdriver and short pin 2 to pin 3 on COM port 1. Be very careful not
to accidentally short any of the other pins, or short to the outer metal shield
around the connector.
Start typing. You should see the key presses echoed on the screen. If you don't
then you probably have a bad COM port and will need to replace it.
If you do see characters being typed then the modem could be bad.
Call
Campbell Scientific
.
10. Remove the paper clips from the back of the RAD modem. Reattach all the
wires to the RAD modem according to your wiring diagram. Plug it back into
the computer's COM 1 port.
11. Take your paper, pen, and screwdrivers with you and go out to the weather
station. Disconnect the SC932C from the datalogger and the RAD modem.
Verify the RAD modem is wired as shown in Figure 3.3-3 in this manual.
Keep in mind that the wires should ultimately be attached as follows:
TABLE 6-1. RAD At Computer [Goes To] RAD At Datalogger
+RCV
→
+XMT
-RCV
→
-XMT
+XMT
→
+RCV
-XMT
→
-RCV
12. Disconnect the wires from the RAD modem. Carefully twist the conductors of
the following wires together:
a. Twist the "-RCV" and "-XMT" wires together.
b. Twist the "+RCV" and "+XMT" wires together.
Make sure these wires don't touch anything else.
13. Take the RAD modem out of the enclosure and back to the computer
Test the RAD modem as explained in steps 2 - 11 in this section.
If the modem is bad,
call Campbell Scientific
.
If the modem checks out then continue.
