Campbell RF232, RF100, RF200, BA1010, BA1012 Instruction Manual

RF FOR RTMS SYSTEMS

INSTRUCTION MANUAL

REVISION: 3

COPYRIGHT (c) 1995 CAMPBELL SCIENTIFIC, INC.

/95

WARRANTY AND ASSISTANCE

The

RF FOR RTMS SYSTEMS

are warranted by CAMPBELL SCIENTIFIC, INC. to be free from defects
in materials and workmanship under normal use and service for twelve (12) months from date of shipment
unless specified otherwise. Batteries have no warranty. CAMPBELL SCIENTIFIC, INC.'s obligation under
this warranty is limited to repairing or replacing (at CAMPBELL SCIENTIFIC, INC.'s option) defective
products. The customer shall assume all costs of removing, reinstalling, and shipping defective products
to CAMPBELL SCIENTIFIC, INC. CAMPBELL SCIENTIFIC, INC. will return such products by surface
carrier prepaid. This warranty shall not apply to any CAMPBELL SCIENTIFIC, INC. products which have
been subjected to modification, misuse, neglect, accidents of nature, or shipping damage. This warranty
is in lieu of all other warranties, expressed or implied, including warranties of merchantability or fitness for
a particular purpose. CAMPBELL SCIENTIFIC, INC. is not liable for special, indirect, incidental, or
consequential damages.

Products may not be returned without prior authorization. To obtain a Returned Materials Authorization
(RMA), contact CAMPBELL SCIENTIFIC, INC., phone [phone]. After an applications engineer
determines the nature of the problem, an RMA number will be issued. Please write this number clearly on
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CAMPBELL SCIENTIFIC, INC.

RMA#_____
815 West 1800 North
Logan, Utah 84321-1784

CAMPBELL SCIENTIFIC, INC. does not accept collect calls.
Non-warranty products returned for repair should be accompanied by a purchase order to cover the repair.

815 W. 1800 N.
Logan, UT 84321-1784
USA
Phone [phone]
FAX [phone]
www.campbellsci.com

Campbell Scientific Canada Corp.
11564 -149th Street
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CANADA
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FAX [phone]

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RF FOR RTMS SYSTEMS

TABLE OF CONTENTS

PAGE

SECTION 1. GENERAL RADIOTELEMETRY NETWORK

1.1 Introduction.............................................................................................................................1-1

1.2 Field Station............................................................................................................................ 1-2

1.3 Base Station...........................................................................................................................1-3

1.4 Repeater.................................................................................................................................1-4

SECTION 2. ASSEMBLING THE RADIOTELEMETRY NETWORK

2.1 Final Layout............................................................................................................................2-1

2.2 Install Base Station.................................................................................................................2-1

2.3 Install Nearest Repeater/Field Station....................................................................................2-2

2.4 Test the Radiotelemetry Link..................................................................................................2-3

2.5 Troubleshooting Unsuccessful Communication Attempts...................................................... 2-3

2.6 Adding Stations to the Net Description...................................................................................2-4

2.7 Radio Test Results.................................................................................................................2-4

SECTION 3. RADIOTELEMETRY NETWORK COMPONENTS

3.1 The RF95T Modem................................................................................................................ 3-1

3.2 RF100/RF200 Radios.............................................................................................................3-4

3.3 Antennas and Cables.............................................................................................................3-5

3.4 Tripods, Towers, Enclosures and Power Supplies.................................................................3-7

3.5 RF232T Base Station.............................................................................................................3-8

SECTION 4. OPERATION OF THE RADIOTELEMETRY NETWORK

4.1 RTMS Notes........................................................................................................................... 4-1

4.2 GraphTerm for DOS Version 2.2 or Newer............................................................................4-3

APPENDICES
APPENDIX A. SETTING THE STATION ID
APPENDIX B. ALTERNATE BASE STATION CONFIGURATIONS
APPENDIX C. POWER CALCULATIONS
APPENDIX D. FUNDAMENTALS OF RADIOTELEMETRY

...........................................................................A-1

..............................B-1

..............................................................................C-1

.............................................D-1

GLOSSARY

i

SECTION 1. GENERAL RADIOTELEMETRY NETWORK

1.1 INTRODUCTION

Data retrieval from a remote site can be difficult.
To accomplish data collection from isolated
sites Campbell Scientific, Inc. utilizes a
radiotelemetry network. Dataloggers can be
accessed by radiotelemetry which requires no
physical connection from the computer to the
datalogger. The radiotelemetry link reduces the
number of visits to a remote site for data
collection.

The radiotelemetry network is designed for
complete computer control. One computer can
establish communication with up to 254 remote
sites (150 per RF232T). The RTMS allows data
collection from the datalogger, transmitting
datalogger programs, and displaying current
readings from the datalogger.

The requirements specific to a radiotelemetry
network include:

• The distance between radio stations should
not be greater than approximately 25 miles.

• The stations should not have major
obstacles between them, therefore, they
should be within line-of-sight of each other.

The stations communicate over a radio
frequency which is specified in Megahertz
(MHz). A data communication network must
have its own specific frequency to prevent
interference from other sources. Typical radio
frequencies are either VHF (Very High
Frequency) ranging from approximately 130 to
174 MHz or UHF (Ultra High Frequency)
ranging from approximately 403 to 512 MHz. A
typical RF system is shown in Figure 1-1.

Telemetry network’s three basic components
are:

• Field Station

• Base Station

• Repeater Station

FIGURE 1-1. A Basic Radiotelemetry Network

1-1

SECTION 1. GENERAL RADIOTELEMETRY NETWORK

1.2 FIELD STATION

Purpose: The field station is where the

measurements are made. The
Campbell Scientific datalogger
resides at this station taking the
desired measurements. Any field
station can also operate as a
repeater. The only requirement is
that the station’s antenna must be
able to communicate in all desired
directions. This may require an
omnidirectional antenna.

ANTENNA

Equipment Required:

• Radio

• RF Modem

• Antenna and antenna cable

• Datalogger

• Power supply, enclosure, sensors, and

mounting needs

1-2

FIGURE 1-2. CR10 Field Station

1.3 BASE STATION

Purpose: A base station utilizes a computer

to collect data from the field
station(s). Normally, all
communication to the field stations
originate at the base station. Data
retrieval, remote programming, and
system analysis can all be done
from the base station.

SECTION 1. GENERAL RADIOTELEMETRY NETWORK

Equipment Required:

• Radio

• RF Base Station

• OS/2 Computer with RTMS software

• Antenna and antenna cable

• AC power

FIGURE 1-3. Base Station

1-3

SECTION 1. GENERAL RADIOTELEMETRY NETWORK

1.4 REPEATER

Purpose: To act as relay between two

communicating stations separated
by too long of a distance or an
obstacle which impedes direct
communication. A repeater is not
always required in a radiotelemetry
network. A field station can also
function as a repeater.

Equipment Required:

• Radio

• RF Modem

• Antenna and antenna cable

• 12V and 5V power supply (PS512M)

• Enclosure and other mounting needs

1-4

FIGURE 1-4. Repeater

SECTION 2. ASSEMBLING THE RADIOTELEMETRY NETWORK

This section provides a logical order for RF network assembly and deployment. Details of specific
components in the system are described in Section 3 “Radiotelemetry Network Components.” This
component section is cross-referenced throughout this assembly section.

2.1 FINAL LAYOUT

The initial locations of the base, field, and
repeater stations have likely been determined
already. Locate RF stations on an area map,
preferably a topographic map. Draw a line
along every communication path. Each field
station must have a path connecting it back to
the base station. No path can be going through
a mountain or large obstacle; this would negate
the line-of-sight requirement. A station may
need to be moved or a repeater station may
need to be added if this requirement is not met.

At each station there is an RF modem. Each
modem requires a unique ID number (Station
ID). The number may range from 1 to 254. On
the map, label the base station as 1. Label the
remaining stations with different ID numbers.
Later, each modem will be set with the
corresponding ID number. The Station ID,
similar to a phone number, allows the base
station to call many different field stations.

2.2 INSTALL BASE STATION

2.2.1 BASE STATION HARDWARE

The major component of the base station is the
RF232T Base Station. Refer to Section 3.5 for
locational drawings and a description of the
RF232T Base Station.

1. Remove the top of the RF232T by
unscrewing the four screws on the sides.

4. Mount the base station antenna in a
location that is higher than any surrounding
buildings or obstacles. Refer to Section 3.3
for more information on mounting the
antenna.

5. After the antenna is mounted, connect the
coax cable between the antenna and the
BNC connector mounted in Step 2.

6. Replace the cover of the RF232T.

7. Connect a large gauge (approximately 8
AWG) copper wire from the antenna to a
good earth ground. This is for lightning
protection. This is required for any
antenna, especially if the coax cable from
the antenna goes inside a building.

8. Connect a 25-pin RS232 cable from the
computer serial port to the RF232T.

9. After verifying that the RF232T power
switch is off, plug in the RF232T's wall
transformer.

2.2.2 REAL TIME MONITORING SOFTWARE (RTMS)

With the base station hardware installed, RTMS
must be setup if it is not already. Refer to the
RTMS manual for specific information on
installing RTMS and for specific information on
the programs described here.

The major components of RTMS are:

2. Remove the radio and its cable from its
mounting bracket. Mount the radio directly
onto the bottom of the RF232T. Secure the
BNC connector from the radio's cable to its
hole on the back of the RF232T. See
Figure 3-7 for assistance.

3. Connect the radio to 12 V, ground, and the
RF Modem. The RF modem is located
behind the front panel above the "POWER
ON" light. See Figure 3-8 for assistance.

CAUTION: Radio transmission without an
antenna connected can damage the radio.

• NetAdmin − Network administration and
health

• RTM − Real Time Monitor for graphical
display of real-time data.

• DBSelect − Data collection and routing.

• DLSMGR − Provides the actual

communication with dataloggers.

2.2.3 NET DESCRIPTION

Ultimately, NetAdmin will be used to describe
the entire network for ongoing communication
with dataloggers in the RF network. However

2-1

SECTION 2. ASSEMBLING THE RADIOTELEMETRY NETWORK

when a valid network description containing
remote sites is “made active” attempts to
communication with the various remote sites
will begin. It is often convenient to test the
individual field/repeater first and add them to the
network description after proper RF
communication is confirmed. This is the
process described in this section.

2.2.4 ADDING THE RF BASE TO THE NET DESCRIPTION

If the RF base is not already part of the network
description, it is necessary to add it. Start the
NetAdmin program and select NET
DESCRIPTION from VIEW on the main menu.
Add RF232T as a child of the computer (PC1).
While all of the parameters will eventually need
to be set, for now alter only the parameters
described here:

• Change the station name (STN NAME box) to

a name meaningful to users of the system.
The default name (RF2) will work but some­thing more recognizable is suggested (i.e.,
RFBase or Office). Names must start with a
letter, contain only letters, numbers, or the ‘_’
character. Names should be unique and be
no longer than eight characters.

• Check the PORT NAME parameter in the

VIA COM PORT box, changing the COM
port if necessary.

• Set the baud rate to 9600.

blue than a warning or fault message has
occurred. If the site is green, successful
communication has occurred. Select
STATUS/WARNING/FAULT under VIEW on
the main menu to see the messages. If “Serline
Timeout Retry On COM?” or a “Link Failed”
fault message has occurred there maybe a
communication problem. See Section 2.2.6.

To verify communication with the RF base
select RF LINK TEST found under VIEW on the
NetAdmin main menu. Select the RF base
station named in the box in the upper left area
of the view. Move the cursor to the
[REPEATER] SWITCH SETTING box. Enter
the ID as set with switches for the RF232T
base. RF232T bases are normally shipped
from the factory with an ID of 1. Select the
BEGIN button. If communication between the
computer and the RF232T is successful the
TEST STATUS/RESULTS box will show the
PROM signature for the RF232T. If the test is
successful, remote sites can be set up.

2.2.6 IF TEST FAILS

Make sure the RF232T is plugged in and is
turned on.

When powered, the RF232T Carrier Detect
Light should blink twice to indicate a successful
memory check. If the light is blinking
continuously, there is a hardware problem (see
Section 3.1.4 for more information on the
Carrier Detect Light).

It is not necessary to add any remote stations
(datalogger sites, etc.) to the net description at
this time. They can be added after the radio
links are tested.

2.2.5 TESTING COMMUNICATION WITH THE RF BASE

When the RF base has been properly
described, select MAKE THE OPEN NET
DESCRIPTION ACTIVE under the FILE option
on the main menu. NetAdmin will prompt for a
file name to save the description if it was not
already saved. Normally it is a good idea to
save the description.

Close the Net Description view. Notice the
main NetAdmin screen. The RF base station
should be shown on the display. Its color will
indicate the last type of message about this
station. If the site is black, no communication
has been attempted yet. If the site is red or

2-2

• Check the Net Description and verify the
COM port and baud rate settings. If the
description is changed it must be “made
active” for the changes to take effect.

• Check that the serial cable is properly
attached to the computer and the RF232T.
It should not be a “Null Modem“ cable.

• Check that the SC12 9-pin ribbon cable
inside the RF232T is connected from the
small circuit board to the RF95T modem.

2.3 INSTALL NEAREST REPEATER/ FIELD STATION

The order in which a general RF field station
should be installed, follows. A repeater station
is installed in the same order. For instructions
on installing any particular component, refer to
either Section 3 of this manual or the Weather
Station Manual.

SECTION 2. ASSEMBLING THE RADIOTELEMETRY NETWORK

1. Tripod or tower

2. Enclosure and datalogger - Turn on
datalogger.

3. Antenna - Orient correctly; remember
direction and polarization.

4. Solar Panel

5. Power Supply

6. Sensors

7. RF Modem - Set the Station ID according to
the map.

8. Radio - Make sure to connect to RF Modem
and to power supply. Connect to antenna
before turning on.

2.4 TEST THE RADIOTELEMETRY LINK

With a field station or repeater installed, return
to the base station for initial testing of the
communication link. An RF link can also be
tested at the field site with a portable base
station; hardware requirements for the portable
base station are described in Appendix B.

At the computer site, start NetAdmin. Select RF
LINK TEST found on the VIEW menu. It is not
necessary to add the field station or repeater to
the net description to test the communication
link. As before, select the RF base in the upper
left box. Move the cursor to the [REPEATER]
SWITCH SETTING box. Enter the ID for the
remote site as set with its switches. Select the
BEGIN button. If the test is successful the
signature of the remote RF95T PROM along
with the quality numbers will be displayed. The
test may take several minutes to complete. The
quality numbers should be examined as they
will help indicate potential problems like outside
interference on the frequency or marginal links.
These numbers are explained in Section 2.7.

2.4.2 AN UNSUCCESSFUL TEST

If the base cannot communicate with the
remote, a TEST FAILED message will be
displayed in the TEST STATUS/RESULTS box.
For links not using a repeater, the problem
could be at the base or the remote site. Section

2.5.1 gives some suggestions that can be tried.
For links utilizing repeaters, start by testing the
link between the RF base and the repeater. It is
not necessary to have a datalogger at a
repeater site to test communication with the RF
TEST LINK. As each part of the link is verified,
add the next segment and test again. With this
method it should be possible to determine which
segment is failing.

2.5 TROUBLESHOOTING UNSUCCESS­FUL COMMUNICATION ATTEMPTS

2.5.1 TROUBLESHOOTING PHYSICAL LINK BETWEEN BASE AND REPEATER/FIELD STATION

When communication is not established,
troubleshooting begins with the simplest RF link
in the system, which is usually communication
with the nearest field station. There is NO
substitute for first checking the hardware
connections, Station IDs, and everything listed
in the previous sections. Below are a few
additional items to check:

1. Antenna is used in proximity of metal.

2. Transmission from inside a building.

3. Damaged or shorted cables.

4. Bad or improper connections.

5. Antenna frequency does not match the

radio frequency.

2.4.1 A SUCCESSFUL TEST

After a successful test, set up the next nearest
site and test that telemetry link. If a repeater is
to be utilized to communicate with a site, enter
the ID of the repeater followed by the ID of the
field site in the [REPEATER] SWITCH
SETTING box. Separate the ids with a space.
When the BEGIN button is selected the entire
link will be tested. The signature of the remote
site will still be returned. An additional row of
quality numbers will be returned for each
repeater.

6. Base and field station radios aren't using

same frequency.

7. Datalogger power drops below 9.6 Volts

during RF transmission. Use datalogger
Instruction 10 or volt meter.

If the field station's RF95T Modem's Carrier
Detect light goes on during a test, then at least
a signal is reaching the site. If this occurs,
check the following:

2-3

SECTION 2. ASSEMBLING THE RADIOTELEMETRY NETWORK

1. RF modem's ID matches ID in the RF Path.

2. Field station's radio and datalogger have
sufficient power.

3. Radio is connected to RF modem.

4. RF modem is the only thing connected to
datalogger's 9-pin connector.

2.6 ADDING STATIONS TO THE NET DESCRIPTION

It is possible to deploy the entire RF datalogger
network, testing the RF links as they are
installed, without adding any of the remote site
to the Net Description. Some users find this
technique desirable. On many other networks it
may be desirable to start data collection from
sites as soon as possible and the sites should
be added to the Net Description after their links
have been tested. The testing of RF links can
continue concurrently with data collection and
other RTMS functions. Some functions may be
delayed slightly due to a RF test or the RF test
may have to wait on other operations. These
delays are usually not significant.

Experience has shown that it is desirable to
verify an RF link with the RF TEST LINK before
adding stations to the Net Description that utilize
that link.

Before adding remote stations to the
description, return to the parameter for the RF
base and ensure that they are set correctly.
The Polling Interval needs to be set for correct
operation as it determines the rate at which the
remote dataloggers are checked for data. Add
the remote field sites as children of the RF
base. Repeater only sites are not added as
nodes. To utilize a repeater (either a repeater
only site or another field site) simply precede
the remote’s ID with the repeater's ID in the VIA
RF MODEM box in the remote’s station
parameters. Separate the IDs with a comma.
Section 5.1 of the RTMS manual gives
additional information on creating Net
Descriptions. Be sure to make the current
description active if any changes are made.

2.6.1 NETWORK HEALTH DISPLAY AND ERROR, WARNING, AND STATUS MESSAGES

As remote sites are added to the network
description, they also appear on the network
health display (NetAdmin main screen). The
color of the site indicates the type of the last
message about that station. Red indicates a
fault message, blue indicates a warning
message, green indicates a status message
(usually successful communication), and black
indicates no communication has been
attempted. Selecting STATUS/WARNING/
FAULT under VIEW on the main menu will
display a box displaying these messages. See
Section 5.5 of the RTMS manual. Messages
regarding remote RF sites are:

• Broadcast failure − A remote did not

respond to a broadcast message.

• Poll failure − A remote did not respond to a

broadcast message or retries.

• Bad link − A remote did not respond to a

direct attempt to communicate with it. Link
will be marked bad.

• Communication restored − A link that was

previously marked bad has been restored.

See Section 3.1.5 for more information on how
RF communication takes place.

2.7 RADIO TEST RESULTS

Completed link test results are shown in the "Test
Status/Results" box. If successful, test results
show the PROM signature of the RF modem
whose switch setting is last in the RF path, and a
communication "Quality Report" with a record for
each hop specified in the path. The number of
"Quality Records" reported in the test response
depends on the number of RF modems listed in
the RF path. If one remote node is listed in the
command then there will be two quality records.
The first record shows how well the remote node
was able to receive from the base, the second
shows how well the base was able to receive from
the remote. With two or more modems listed in
the path, the first quality record will indicate how
well the most remote modem received. The rest
of the quality records show how well data was
received with each hop going from the most
remote node back to the base. So, if two RF
modems were listed in the test path, there would
be three quality records in the response. The

2-4