WATSON INDUSTRIES SMS-P233 User manual

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STABILIZED MOUNT SYSTEM
OWNER'S MANUAL
PART NUMBER: SMS-P233
WATSON INDUSTRIES, INC.
3035 MELBY STREET
EAU CLAIRE, WI 54703
Phone: [phone]
FAX: [phone]
email: [e-mail]

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Table Of Contents
Introduction................................................................................................................... 3
Product Description...................................................................................................... 3
Start-Up..........................................................................................................................................................................5
Time Constant................................................................................................................................................................5
Pointing Angle...............................................................................................................................................................6
Error Correction.............................................................................................................................................................6
Centrifugal Force:......................................................................................................................................................6
Delta Velocity:...........................................................................................................................................................6
Moment Arm: ............................................................................................................................................................6
Safety Features...............................................................................................................................................................6
Over-current detection shut down:.............................................................................................................................6
Electronic limit stop:..................................................................................................................................................6
Mechanical limit stop:................................................................................................................................................6
Reverse power connection:........................................................................................................................................7
Installation .................................................................................................................... 7
Mounting:.......................................................................................................................................................................7
Servo System: ............................................................................................................................................................7
Sensor Package:.........................................................................................................................................................9
Environment: .................................................................................................................................................................9
Connections: ................................................................................................................................................................10
Power:..........................................................................................................................................................................10
Specifications.............................................................................................................. 10
Specifications.............................................................................................................. 11
RS-232 Output Format ............................................................................................... 12
RS-232 Input Commands ........................................................................................... 13
Warning ...................................................................................................................... 15
Appendix A................................................................................................................. 17
Appendix B................................................................................................................. 20
Activating Command Mode (Double Spacebar Mode)................................................................................................20
Determining Output Channels .....................................................................................................................................20
Setting Output Channels ..............................................................................................................................................21
Adjust Time Constant ..................................................................................................................................................21
Set Baud Rate...............................................................................................................................................................22
Watson Industries prides itself on solving customer problems and serving their needs in a timely fashion. This manual
is intended to facilitate this goal and to provide written information about your product. We ask that you carefully read
this manual. Becoming familiar with the manual will help you understand the product’s capabilities and limitations, as
well as provide you with a basic understanding of its operation. If, after reading the manual, you require further
assistance, do not hesitate to call Watson Industries with your questions and comments.

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CAUTION!
Watson Sensors are rugged devices that have been used successfully in a number of harsh
environments. The components have been qualified to withstand a mechanical shock of 200g 's or
greater, and most enclosures provide an added level of protection. However, dropping a sensor
from waist height onto a hard floor can cause a shock level of 600g's. At this level, damage is
likely to occur.
Introduction
This manual is intended to help in understanding the installation and operation requirements of the
Watson Stabilized Mount System. Details of the operation and adjustments are provided to allow
the owner to obtain optimum performance from this product.
Product Description
Watson Industries has many years of experience developing sensor packages for stabilized
platforms for camera and antenna applications. Now we have taken the next step and are offering a
complete system.
Our gyro-stabilized mount system is built around a rugged pan and tilt mechanism. This is a high-
resolution digital system that uses high quality, wide bandwidth, low noise, and solid-state gyros.
Watson's proprietary rate closure, zero error algorithms takes preset attitude angles from a micro
controller and drives a digital servo controller in the mount. The whole system is user configurable
to adapt to a wide range of payloads and requirements.
Watson Industries also provides custom systems for special requirements. Our system design is
modular and configurable for economical and quick adaptation to a wide variety of hardware
configurations. Of course Watson Industries’ excellent product support and applications
engineering goes along with every product.
This particular model of the Watson product line is intended to hold an up to a 99 pound (45 Kg)
payload aligned to level and horizontal on a moving vessel/vehicle

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Figure 1 Two-axis gyro Stabilized Mount installation
Each axis comprises a servomotor, driving the platform through an anti-backlash gear, a precision
potentiometer for positional measurements, and a pair of limit stops. The anti-backlash gear
minimizes the backlash from platform motions to less than 10 Arc Seconds. Furthermore, Watson
Industries has installed two gyros and a triaxial accelerometer used to calculate corrective
commands to the drive motors.
The two gyros are rugged vibrating-structure gyroscopes, whose angular rate signals are converted
from analog to 16-bit digital form. The effects of temperature variation on the DC bias of the gyros
are digitally corrected.
The micro controller assesses the desired motion of the platform based on preset angles in its
memory. It then compares this desired motion against the real motion of the platform, sensed by
the gyros and accelerometers, developing a rate error value. A servo-control system (P.I.D.
algorithm), uses the current (Proportional), past (Integral), and predicted future (Differential) value
of this error to derive a motor voltage that will drive the error to zero. In other words, the servo-
control system ensures that the motion of the platform exactly matches that of the preset value in
inertial space.
Y

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The servo driver module in the mount enclosure accepts commands from the micro controller in
digital form, converts them to pulse-width modulation using two full-bridge switching motor
drivers and then applies this to the two motors.
The platform is carefully designed to be rugged and reliable. Particular attention has been paid to
minimizing the effects of noise at every point in the system. This ensures that full advantage can
be taken of the low noise performance of the gyroscopes to achieve a highly stable platform.
Operation
Start-Up
The system is automatic. Once power is applied, the stabilized mount system will drive to its
preset attitude angles with errors corrected at a short time constant. The time constant of the
correction will be increased in increments until it reaches the full operational time constant.
Time Constant
The operational time constant of error correction is chosen for the predicted influences on the
accuracy of the system. Chief among the sources of error are the dynamics of the vehicle and the
drift tendencies of the gyroscopes.
Vehicle dynamics are characterized as being violent when they exist for a short time and gentle
when they are sustained over a long period. They are derivative in nature. In contrast, gyroscopes
have little error on the short term, but grow rapidly as the errors accumulate in the system. They
are integral in nature. The time constant must be chosen to match the circumstances such that the
least error is likely as shown in example below:
0.01
0.1
1
10
100
1000
1 10 100 1000 10000
Seconds
Error (Degrees)
Dynamic Disturbances
Sensor Drift
Figure 2 Errors versus Time Constant
The correction time constant for this system is adjustable by the conditions detected by the system.
When increasing errors are detected, the time constant is made longer so that the gyros are in more
control of the attitude. This is done on the assumption that short-term errors are more likely to be
caused by vehicle dynamics.

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The dynamics of an aircraft or a large ship or a small ship or a land vehicle will all have individual
patterns and intensities. Only experience will expose the best time constant setting for lowest error.
The time constants are settable by the user through the RS-232 connections of the unit.
Pointing Angle
The nominal preset attitude angles are set to level and horizontal. Full ranges of offsets to this
starting point (within mechanical limits) are settable by the user through the RS-232 connections of
the unit.
Error Correction
Short-term disturbances will be held off from affecting the stable mount system, but as these errors
become longer term, corrections or preventative actions will be required.
Centrifugal Force:
The centrifugal force from turns at a significant speed will pull the pointing angle into error over
time. There are two ways to limit this effect:
1. Set the system time constant to a higher time interval.
2. Send a “Free Mode” command (essentially an infinite time constant) to inhibit the vertical
reference accelerometers from influencing the pointing angle. This is for short-term use
only on the order of a couple of minutes.
Delta Velocity:
The compensation for forward acceleration is done just as that for centrifugal force.
Moment Arm:
Rotation motions of the vehicle will produce errors that are a function of the distance from the
center of rotation, the moment arm. The compensation for this is to increase the time constant.
Safety Features.
Over-current detection shut down:
There is current sensing for each axis of this system that connects to the micro controller. If
sustained excessive motor current is detected (i.e. greater than one amp on either axis), the system
will shut down. Since the components of the system are balanced, the only regular cause of
sustained over current is driving against resistance such as an obstruction. Such a load on the
system could cause a burn out of the motor and this must be prevented. The power will have to be
turned off, the obstruction must be cleared and the power will then have to be restored in order to
reboot the system.
Electronic limit stop:
The system tracks the orientation of the mount by reading the potentiometer outputs and will
prevent driving past a preset angle value held in the micro controller’s non-volatile memory.
Driving the mount away from this limit is not inhibited.
Mechanical limit stop:
This is a mechanical limit adjusted to keep the mount from colliding with its structure. It uses
micro switches to turn off the ability to drive further into the stop by interrupting one side of the
motor driver. This is a last line of defense from a system failure, as it is fully independent from the
other safety systems. Driving the mount away from this limit is not inhibited.

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Reverse power connection:
Power is diode protected from voltage polarity reversal. Recovery is immediate and without
damage.
Installation
The servo system is mounted to the post with
careful alignment and bolted together.
Additionally, the payload (supplied separately)
must be attached to the SMS. The steps for this
process are described below and should be read
and understood before any installation or
assembly begins.
WARNING – Do not apply power until the
installation is complete!
Mounting:
Servo System:
The servo system is the part of the SMS that will hold the payload level and horizontal. The servo
system consists of the main servo housing and the sensor package mounting arm. The main servo
housing has a circular plate with M6 threaded holes. Four M6 bolts and four M6 washers are
provided to mount the servo system to its mounting place. Several steps should be followed for a
proper installation of the servo system:
1. The servo system is heavy and must be supported
during installation to its mounting place.
2. Adjust the position of the mounting ring of the servo
system so that the paint mark on the mounting ring
will line up with the center position of the intended
field of view.
Stop Pin
Paint Mark

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3. Loosely attach the servo system to the mounting position using four mounting
bolts, washers and possibly nuts. Use bolts that do not protrude beyond the
mounting ring.
4. Adjust the position of the servo system so that the paint
marks on the mounting position and mounting ring are in
line with the stop pin.
5. Using a level, adjust the position of the servo system so that it is reasonably level.
6. Once the servo system is completely level, secure the four M6mounting bolts.

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Sensor Package:
Once the servo system is correctly installed, a payload may be installed on the mounting arm of the
servo system. The SMS has no counterweight and is limited by this load imbalance to 99 lb (45
Kg) payload. WARNING – Do not apply power until the installation is complete!
Environment:
This product has been surface treated for resistance to salt air and precipitation. As always, this
resistance is limited and the system should be kept clean and should be inspected for signs of
corrosion damage regularly.
As in all moving mechanisms there is concern about ice interfering with operation. The system has
internal protection against damage from stalling the motors, but performance may be reduced.
The system should be considered fragile. DO NOT APPLY LOADS OR FORCES TO THE
PAYLOAD.

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Connections:
This product has one connector for all system connections. The user mating connector is
Amphenol part number MS3106A-20-7S (included with the system). The connections are:
Pin Function
A Power Return
B +28 Volt Power
C No Connection
D RS-232 Transmit from SMS-P233
E Signal Ground (connected internally to Power Return)
F RS-232 Receive to SMS-P233
G No Connection
H Case Ground
Power:
This unit has an internal regulator to allow operation over a moderate voltage input range. Best
operation is obtained at 28 VDC level, although operation is fully satisfactory down to 18 VDC and
up to 30 VDC. Current draw of the unit is about 3 amperes peak. Internal capacitors are provided
to remove a reasonable level of power line noise, however, capacitors should be added for long
power line wiring or if noise is induced from other loads on the circuit.

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Specifications
Platform
Range: Bank, Elevation ±30° (Electronic) ±45° (Mechanical)
Slew Rate: Bank, Elevation ±45°/sec
Attitude Accuracy: Static ±1.5°
Attitude Accuracy: Dynamic ±3.0°
Noise: 0.1° rms
Stability: ±1.5° Over 20 minutes
Environmental
Temperature: Operating -20°C to +50°C
Temperature: Storage -50°C to +80°C
Vibration: Operating 0.2 g rms 100 Hz to 1 KHz
Vibration: Survival 0.5 g rms 100 Hz to 1 KHz
Electrical
Startup Time: Operational 5 seconds
Startup Time: Full Performance 90 seconds
Input Power: 18 to 30 VDC
Input Current: 2A @ 28VDC 6A Peak
Physical
Size: Including Mounting Flanges 8.9"W x 15.8"L x 7.3"H 22.6 x 40.1 x 18.5 (cm)
Weight: 28lb (12.7Kg) Not including payload
Connection: MS3102A-20-7P Mating connector included
Base Mounting Holes: Qty 8 (4 x M6 threaded; 4 x #12
M6 clearance) 4" dia. bolt circle
Payload Mounting Holes: Qty 8 #12 (M6) clearance 4" dia. bolt circle
• Specifications are subject to change without notice.
• This product may be subject to export restrictions. Export Classification ECCN EAR99.

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RS-232 Output Format
The “as shipped” default setting for serial communications is to inhibit the text header initialization
message and to inhibit serial data. That is to say no data would come out of the system. The user
as described below can change this default setting.
The nominal RS-232 output consists of a string of decimal ASCII characters sent asynchronously at
regular intervals at about 10 strings per second when not inhibited. The string is set to be sent at
9600 baud with eight data bits, one stop bit and no parity. The factory set for the contents of the
string is formed as follows:
1. A seven character string representing the bank angle starting with a “+” or a “-“, followed
by three digits, a decimal point, one digit and a space for up to ±179.9 degrees.
2. A six character string representing the elevation angle starting with a “+” or a “-“, followed
by two digits, a decimal point, one digit and a space for up to ±89.9 degrees.
3. A six character string representing the X axis accelerometer starting with a space, then a
“+” or a “-“, followed by one digit, a decimal point and two digits for up to ±9.99 g.
4. A six character string representing the Y axis accelerometer starting with a space, then a
“+” or a “-“, followed by one digit, a decimal point and two digits for up to ±9.99 g.
5. A six character string representing the Z axis accelerometer starting with a space, then a “+”
or a “-“, followed by one digit, a decimal point and two digits for up to ±9.99 g.
6. A six character string representing the X axis angular rate starting with a “+” or a “-“,
followed by two digits, a decimal point, one digit and a space for up to ±99.9
degrees/second.
7. A six character string representing the Y axis angular rate starting with a “+” or a “-“,
followed by two digits, a decimal point, one digit and a space for up to ±99.9
degrees/second.
8. The string is terminated by a carriage return. There will then be a short interval with no
data transmission before the next string begins.
Example:
+002.5 -01.5 -0.01 -0.04 -1.00 +02.5 -05.0 <CR>
Bank
Angle
(1)
Elev.
Angle
(2)
X Axis
Accel
(3
Y Axis
Accel
(4)
Z Axis
Accel
(5)
X Axis
Rate
(6)
Y axis
Rate (7)
(8)
↑ ↑ ↑ ↑ ↑ ↑
space space space space space space
This may be reduced to more basic information to improve the update rate to compensate for lower
baud rate by using special commands to modify the EEPROM of the unit.

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The system is protected from inadvertent write-over of the EEPROM by requiring two spacebar
commands during the initialization interval to access the EEPROM or related functions.
The baud rate may be changed from the nominal value of 9.6K baud by modifying the default value
in the EEPROM of the unit to 38.4K, 19.2K, or 4.8K baud.
A text header is sent by the SMS during initializations that identifies the unit by part number and
by serial number and gives the date of last calibration. Additionally, a line of text characters that
identifies the data channel columns is sent if the serial output is set to ASCII decimal. This whole
message can be suppressed or restored by a “*” command from the interfacing computer. Such a
change in setting can be made the default setting.
Data transmission sent by the SMS-P233 can also be suppressed or restored by a “+” command
from the interfacing computer. This change can be made the default setting.
The error over range condition occurs when error exceeds the ranges preset in the system
EEPROM. When this happens, the system will continue to operate in an extended time constant
mode with a low level of error accumulation until the condition is cleared. Occasional blips of this
condition are expected with little detectable affect on the resulting data.
RS-232 Input Commands
The RS-232 input commands are provided for the purpose of unit test and installation set-up. Use
the same parameters that are used for the RS-232 output (9600 baud ASCII nominal, or as reset in
the units EEPROM).
Note: Many commands require command or “Double spacebar mode” in order to access them. For
more information on how to activate Command Mode, see the instructions in Appendix B.
These commands are available to the user (others are used at the factory for alignment and
calibration).
1. An “F” will disconnect the references from the attitude system and is the Free Mode
Command. This coast mode is used to make the system ignore the references during highly
dynamic maneuvers and brief disturbances. This mode is not intended for use except in
brief intervals of a minute or two, since errors will grow geometrically.
2. A “K” will clear the Free Mode Command.
3. An “!” will reinitialize the unit. Further, the access to initialization is inhibited such that a
spacebar command must be sent within 2.5 seconds of the “!” command for initialization to
be engaged.
There are several interface commands: “:” will toggle the output to send a frame of data upon
receiving any non-command character and “+” will toggle the output for no output data. These
and other changes are made non-volatile (default) in the unit on EEPROM by keying in the quote
(“) character. Double spacebar at initialization is required for access to these commands. Note that
the “:” setting will cause the mechanical brake to be engaged between frames. This is not intended
to be an operational mode.

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The “&” command calls up the main menu which allows any of several parameters to be set.
These are system time constants, selection of data channels for serial output, listing current serial
channels and baud rate. Double spacebar at initialization is required for access to this command.
The commands “~”, “@”, “#”, “$”, “(“, “)”, “{“, “}”, “|”, “<”, “>” and “?” are used by the Watson
factory to calibrate the unit and should be used only with the assistance of the factory. If an
undesired function is called, a “Q”, and sometimes Escape or a Delete will interrupt the command
and return to operation with the least disturbance to the system. All other unspecified characters
such as carriage return, line feed and space are ignored by the system.

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Warning
Rough handling or dropping of this unit is likely to cause damage.
Over-voltage and/or miswiring of this unit will cause damage.
This unit should be inspected regularly during any prolonged exposure to
high humidity and/or salt air environments.
DISCLAIMER
The information contained in this manual is believed to be accurate and reliable; however, it is the
user’s responsibility to test and to determine whether a Watson Industries’ product is suitable for a
particular use.
Suggestion of uses should not be taken as inducements to infringe upon any patents. This product
is not to be used as a primary instrument for life critical use.
WARRANTY
Watson Industries, Inc. warrants, to the original purchaser, this product to be free from defective
material or workmanship for a period of two full years from the date of purchase. Watson
Industries’ liability under this warranty is limited to repairing or replacing, at Watson Industries’
sole discretion, the defective product when returned to the factory, shipping charges prepaid, within
two full years from the date of purchase. All sensors returned under warranty will be repaired (or
replaced at the sole option of Watson Industries) at no cost to the customer other than shipping
charge from customer to Watson Industries (plus any export and transportation charges outside the
United States). The warranty described in this paragraph shall be in lieu of any other warranty,
express or implied, including but not limited to any implied warranty of merchantability or fitness
for a particular purpose.
Excluded from any warranty given by Watson Industries are products that have been subject to
abuse, misuse, damage or accident; that have been connected, installed or adjusted contrary to the
instructions furnished by seller; or that have been repaired by persons not authorized by Watson
Industries.
Watson Industries reserves the right to discontinue models, to change specifications, price or
design of this product at any time without notice and without incurring any obligation whatsoever.
The purchaser agrees to assume all liabilities for any damages and/or bodily injury, which may
result from the use, or misuse, of this product by the purchaser, his employees or agents. The
purchaser further agrees that seller shall not be liable in any way for consequential damages
resulting from the use of this product.
No agent or representative of Watson Industries is authorized to assume, and Watson Industries
will not be bound by any other obligation or representation made in connection with the sale and/or
purchase of this product.
PRODUCT LIFE
The maximum expected life of this product, other than wear out, is 20 years from the date of
purchase. Watson Industries, Inc. recommends the replacement of any product that has exceeded
the product life expectation.

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Customer Service
All repairs, calibrations and upgrades are performed at the factory. Before returning any product,
please contact Watson Industries to obtain a Returned Material Authorization number (RMA).
Return Address & Contact Information
Watson Industries, Inc.
3035 Melby Street
Eau Claire, WI 54703
ATTN: Service Department
Telephone: [phone] Fax: [phone] email: [e-mail]
Returning the Product
Product shall be packaged making sure there is adequate packing around all sides. Correspondence shall
include:
• Customer’s Name and Address
• Contact Information
• Equipment Model Number
• Equipment Serial Number
• Description of Fault
It is the customer’s responsibility to pay all shipping charges from customer to Watson
Industries, including import and transportation charges.

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Appendix A
The following outputs are available via the RS-232 serial link. Their full-scale ranges are listed for decimal format.
Inertial Output Full Scale Decimal
Time 0 to 999.9 s
Bank Angle ±179.9º
Elevation Angle ±89.9º
X Angular Rate ±99.9 º/s
Y Angular Rate ±99.9 º/s
X Accelerometer ±9.99 g
Y Accelerometer ±9.99 g
Z Accelerometer ±9.99 g
X Potentiometer ±179.9º
Y Potentiometer ±179.9º
X Current 0 to 2.00 Amps
Y Current 0 to 2.00 Amps
Temperature -40º to 88ºC
Status Bits 2 ASCII chars representing
Octal digits
Flag Bits 1 2 ASCII chars representing
Octal digits
Flag Bits 2 3 ASCII chars representing
Octal digits
Status Bits:
The status bits provide operational information that is presented as two ASCII octal digits. The
first digit is made from three bits as follows:
1) Initialization mode equals a value of 1 during start up.
2) Bank error limit equals a value of 2 when large Bank errors occur.
3) Elevation error limit equals a value of 4 when large Elevation errors occur.
First
Digit Elevation Error Limit Exceeded Bank Error Limit Exceeded Initialization
7 Yes Yes Yes 4 + 2 + 1
6 Yes Yes No 4 + 2
5 Yes No Yes 4 + 1
“4” Elev. Limit Exceeded
4 Yes No No 4
“2” Bank Limit Exceeded
3 No Yes Yes
2 + 1 “1” In Initialization
2 No Yes No 2
1 No No Yes 1
0 No No No

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The second digit represents the current time constant as a power of two:
TC = 2
X
Seconds
The nominal time constant is 16 seconds which would display the octal value of X as “4”.
Second
Digit Time Constant (seconds)
7 128
6 64
5 32
4 16
3 8
2 4
1 2
0 1
Flag Bits 1:
The flag bits present warning information. The first digit is:
1) Bank angle positive stop limit equals a value of 2 when the Bank potentiometer reaches
a preset limit.
2) Bank angle negative stop limit equals a value of 1 when the Bank potentiometer reaches
a preset limit.
Second
Digit Bank Angle Positive Stop Limit Bank Angle Negative Stop Limit
2 Yes No 2
“2” Bank Positive Stop Limit
1 No Yes 1
“1” Bank Negative Stop Limit
0 No No
The second digit is made from three bits as follows:
1) Elevation angle positive stop limit equals a value of 2 when the Elevation potentiometer
reaches a preset limit.
2) Elevation angle negative stop limit equals a value of 1 when the Elevation
potentiometer reaches a preset limit.
Second
Digit Elevation Angle Positive Stop Limit Elevation Angle Negative Stop Limit
2 Yes No 2
“2” Elevation Positive Stop Limit
1 No Yes 1
“1” Elevation Negative Stop Limit
0 No No

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Flag Bits 2:
The flag bits present warning information. Flag Bits 2 is made from three digits as follows:
The first digit is made from two bits as follows:
1) Input Power greater than 30 Volts equals a value of 2.
2) Input Power less than 18 Volts equals a value of 1.
First Digit Input Power
2 Greater than 30 VDC (Over voltage)
1 Less than 18 VDC (Under voltage)
0 Between 18 & 30 VDC (Acceptable)
The second digit is made from two bits as follows:
1) Bank over current limit equals a value of 2 when the Bank motor is overloaded.
2) Elevation over current limit equals a value of 1 when the Elevation motor is overloaded.
Second
Digit Bank Motor Overload Elevation Motor Overload
3 Yes Yes 2 + 1
2 Yes No 2
“2” Bank Motor Overload
1 No Yes 1
“1” Elevation Motor Overload
0 No No
The third digit is made from two bits as follows:
1) X Rate limit equals a value of 2 when the X axis angular rate exceeds 25 degrees per
second.
2) Y Rate limit equals a value of 1 when the Y axis angular rate exceeds 25 degrees per
second.
Third
Digit X Axis Rate Limit Exceeded Y Axis Rate Limit Exceeded
3 Yes Yes 2 + 1
2 Yes No 2
“2” X Rate Limit Exceeded
1 No Yes 1
“1” Y Rate Limit Exceed ed
0 No No

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Appendix B
Activating Command Mode (Double Spacebar Mode)
1) Connect the unit to a DC power source that is off .
2) The viewing computer needs a valid bi-directional RS-232 serial port. Connect the serial
port of the Watson sensor to the computer’s serial port.
3) Open a terminal program (such as HyperTerminal) to interface with the unit. The default
baud rate of the unit is 9600 baud. Make sure the computer’s serial port is open.
4) Power-on the unit. A startup message will be transmitted by the unit and will appear in the
terminal window unless it has been suppressed (See RS-232 Input Commands above).
5) During initialization, hit the space bar twice within close succession.
Note: The sensor initialization time begins after the startup message is transmitted.
Typically, this time period lasts 5 seconds, but could be as long as 127 seconds depending
on your sensor.
6) Wait until after initialization is finished. At this point, command mode will be activated and
the unit will accept keyboard commands.
Note: Most Watson sensors have initialization times that are shorter than 30 sec. Any extra
keystrokes (other than two spacebars) sent during initialization will deactivate command
mode.
**It can often take a few attempts to get the hang of step 5. Repeat steps 4-6 until successful.
Determining Output Channels
1) Activate Command Mode (See above).
2) To determine which channels are present, first type '&'.
This will bring up the main menu:
3) Typing in '3' will show which channels are currently active.
TYPE IN THE NUMBER OF YOUR SELECTION (OR 'Q' TO QUIT):
1 = ADJUST TIME CONSTANTS
2 = SET OUTPUT CHANNELS
3 = LIST CURRENT OUTPUT CHANNEL SELECTION
4 = SET NEW BAUD RATE