Advantech AWMA - C250 User manual

INSTALLATION AND OPERATING MANUAL
REDUNDANT 250W C-BAND HUB-MOUNT
SOLID STATE POWER AMPLIFIER
AWMA – C250
PM 100-415550-220, REV. 3

AWMA-C250
Page 1
WARRANTY
This ADVANTECH Advanced Microwave Technologies, Inc. product is warranted against
defects in material and workmanship for a period of 2 years from date of shipment. During the
warranty period, ADVANTECH Advanced Microwave Technologies, Inc. will, at its option,
either repair or replace products that will prove to be defective.
To return a product for warranty or repair service, you must first request a Return Material
Authorization (RMA) number by contacting ADVANTECH at:
Phone: [phone] or Fax: [phone]
Website:
www.AdvantechAMT.com or e-mail: [email protected]
The unit should be shipped to the following address, in original shipping container (box), with
shipping charges prepaid.
ADVANTECH Advanced Microwave Technologies, Inc.
657 Orly Avenue
Dorval, Quebec
H9P 1G1
CANADA
Please indicate the RMA number on all shipping documentation.
Units shipped without prior issued RMA, or shipped not in original packing, may be subject of
rejection and returned at sender’s own expense.
LIMITATIONS OF WARRANTY
ADVANTECH Advanced Microwave Technologies, Inc. warrants this product to be free of
materials and workmanship defects.
The foregoing warranty shall not apply to defects resulting from improper handling or abuse by
the Buyer, unauthorized modification, operation outside of the environmental specifications for
the product, or improper installation or maintenance.
ADVANTECH Advanced Microwave Technologies, Inc. shall not be liable for any direct,
indirect, special, incidental or consequential damages.

AWMA-C250
Page 2
CONTENTS
1. SAFETY ...............................................................................................................................................................6
2. GENERAL INFORMATION.............................................................................................................................9
3. MAJOR SUBSYSTEMS AND THEIR FUNCTIONS ...................................................................................13
3.1 RF SUB-SYSTEM...........................................................................................................................................13
3.1.1 RF High Power Module...............................................................................................................13
3.1.2 RF Driver Module..........................................................................................................................13
3.1.3 Waveguide Arm Assembly ...........................................................................................................14
3.1.4 RF Input Isolation Circuit...........................................................................................................14
3.2 THE REDUNDANT WAVEGUIDE SWITCH ASSEMBLY .....................................................................................14
3.3 THE REDUNDANT FRAME ASSEMBLY ...........................................................................................................14
3.4 POWER SUPPLY SUBSYSTEM.........................................................................................................................17
3.5 MONITOR AND CONTROL BOARD ................................................................................................................17
3.6 THE COOLING SUBSYSTEM...........................................................................................................................18
3.7 LRU PHILOSOPHY........................................................................................................................................18
4. UNPACKING AND INSTALLATION............................................................................................................19
4.1 INITIAL INSPECTION......................................................................................................................................19
4.2 UNPACKING..................................................................................................................................................19
4.3 INSTALLATION..............................................................................................................................................19
4.3.1 Mechanical Installation................................................................................................................19
4.3.2 Electrical Connections.................................................................................................................21
4.3.3 RF Connections..............................................................................................................................23
4.3.4 Cooling Considerations ...............................................................................................................23
5. INTERFACES ...................................................................................................................................................25
5.1 SERIAL INTERFACE (1:1 REDUNDANT SYSTEM) ...........................................................................................26
5.2 DISCRETE INTERFACE...................................................................................................................................27
5.3 RF OUTPUT MONITOR PORT ........................................................................................................................29
6. INITIAL POWER ON AND CHECKOUT.....................................................................................................30
6.1 PRE-POWER PROCEDURES ............................................................................................................................30
6.1.1 Verifying the Operational Settings............................................................................................30
7. OPERATION.....................................................................................................................................................31
7.1 INTRODUCTION.............................................................................................................................................31
7.2 ESSENTIAL OPERATING PROCEDURES ..........................................................................................................31
7.3 PREPARING THE SERIAL INTERFACE .............................................................................................................32
7.3.1 Software Installation and Set-up...............................................................................................32
7.3.2 Wiring Instructions........................................................................................................................32
7.3.3 Software Configuration...............................................................................................................33
7.4 RF CONFIGURATION.....................................................................................................................................34

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7.4.1 Safety Considerations...................................................................................................................34
7.4.2 Setting RF Output ..........................................................................................................................34
7.5 SETTING MINIMUM OUTPUT POWER THRESHOLD ........................................................................................34
7.6 AMPLIFIER SHUTDOWN ................................................................................................................................35
7.7 ALARMS AND FAULTS ..................................................................................................................................35
7.8 RESETTING THE UNIT...................................................................................................................................35
7.8.1 Clearing Faults...............................................................................................................................36
7.9 USING THE SOFTWARE INTERFACE...............................................................................................................36
INITIAL MENU (SCREEN) PAGE...........................................................................................................37
MENU (SCREEN) PAGE #1 ......................................................................................................................38
MENU (SCREEN) PAGE #2 ......................................................................................................................40
MENU (SCREEN) PAGE #3 ......................................................................................................................41
8. MAINTENANCE...............................................................................................................................................42
8.1 PREVENTIVE MAINTENANCE ........................................................................................................................42
8.1.1 Mechanical Preventive Maintenance.......................................................................................42
8.1.2 Checking the Cooling fan............................................................................................................42
8.2 MODULE REPLACEMENT PROCEDURES ........................................................................................................43
8.2.1 Shroud Disassembly......................................................................................................................43
8.2.2 Fan Replacement............................................................................................................................43
8.2.3 Waveguide Arm Replacement.....................................................................................................43
8.2.4 Power Supply Replacement (A1, A2) .......................................................................................43
8.2.5 RF Driver Module Replacement (A4)......................................................................................43
8.2.6 RF Power Module Replacement (A3).......................................................................................44
8.2.7 Monitor and Control Board Replacement (A5).....................................................................44
9. APPENDIX – A: ELECTRICAL SPECIFICATIONS ..................................................................................45
10. APPENDIX – B: PACKING LIST...............................................................................................................46
11. APPENDIX – C: MODULE REPLACEMENT..........................................................................................47
12. APPENDIX - D: SAFETY AND EMC COMPLIANCE............................................................................48

AWMA-C250
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FIGURES
FIGURE 1: PRODUCT OUTLINE ...................................................................................................... 10
FIGURE 2: PRODUCT OUTLINE (EACH UNIT).................................................................................. 11
FIGURE 3: BLOCK DIAGRAM (ONE UNIT)....................................................................................... 12
FIGURE 4: CONNECTORS SIDE OF ONE UNIT................................................................................... 15
FIGURE 5: BLOCK DIAGRAM 1:1 REDUNDANT SYSTEM................................................................ 16
FIGURE 6: MAIN FRAME ASSEMBLY ............................................................................................. 20
FIGURE 7: DISCRETE INTERFACE – PROPOSED MONITOR AND CONTROL CIRCUIT........................ 29
FIGURE 8: INITIAL PAGE OF THE COMMUNICATION PROGRAM...................................................... 37
FIGURE 9: PAGE #1 OF THE COMMUNICATION PROGRAM ............................................................. 38
FIGURE 10: PAGE #2 OF THE COMMUNICATION PROGRAM ........................................................... 40
FIGURE 11: PAGE #3 OF THE COMMUNICATION PROGRAM ........................................................... 41

AWMA-C250
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TABLES
TABLE 1: CONNECTORS (EACH UNIT)..................................................................................... 15
TABLE 2: AC LINE (J5) – PIN ASSIGNMENTS (EACH UNIT)................................................. 17
TABLE 3: MECHANICAL SPECIFICATIONS ........................................................................ 21
TABLE 4: POWER (EACH UNIT)................................................................................................. 22
TABLE 5: ENVIRONMENTAL CONDITIONS........................................................................ 24
TABLE 6: RS-485 INTERFACE................................................................................................. 24
TABLE 7: SERIAL INTERFACE (J2) – PIN ASSIGNMENTS (EACH UNIT)............................ 26
TABLE 8: DISCRETE INTERFACE (J3) – PIN ASSIGNMENTS (EACH UNIT) ...................... 28
TABLE 9: SERIAL INTERFACE (P1) CONNECTION INFORMATION............................... 33
TABLE 10: ELECTRICAL SPECIFICATIONS......................................................................... 45

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1. SAFETY
In addition to this section, included by reference are the following pertinent sections of the
International Standard IEC-215, ‘Safety requirements for radio transmitting equipment’:
Appendix D, ‘GUIDANCE ON ASSESSING THE COMPETENCE OF PERSONNEL FOR
DESIGNATION AS SKILLED’ and also Sub-clause 3.1 of the Standard.
Appendix E, ‘GUIDANCE ON SAFETY PRECAUTIONS TO BE OBSERVED BY
PERSONNEL WORKING ON RADIO TRANSMITTING EQUIPMENT’, also Sub-clauses 3.2,
3.7 and 22.1 of the Standard.
To prevent the risk of personal injury or loss related to equipment malfunction Advantech uses
the following symbols for safety related information. For your own safety, please read the
information carefully BEFORE operating the equipment.
Symbols used in manual:
WARNING: This indicates a hazardous procedure that could result in serious injury or death if
not performed properly.
CAUTION: This indicates a hazardous and danger procedure that could result in light-
to-severe injury or loss related to equipment malfunction, if proper precautions
are not taken.

AWMA-C250
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----------------------------------------------- WARNING -----------------------------------------------------
When supplying power to this equipment, use the 3-pin connector provided to connect to a
grounded power outlet; also use a ground strap between the station’s ground bus and the
ground screw located on the SSPA frame and redundancy frame. If power is supplied without
grounding to the equipment, there is a risk of receiving a severe or fatal electric shock.
In the context of this document any voltage that is lethal is viewed as ‘High Voltage’. Therefore,
even prime power (180 to 268 VAC) is dangerous because prime power potentials have been
known to cause death or injury.
----------------------------------------------- WARNING ----------------------------------------------------
This equipment can not be repaired by the operator. DO NOT attempt to remove the
equipment cover or to disassemble internal components. Only qualified service technicians
should service this equipment. There are high-voltage parts in this equipment presenting a risk of
severe injury to untrained personnel. In addition, there is a risk of damage to precision
components.
----------------------------------------------- WARNING ----------------------------------------------------
ALWAYS TERMINATE THE OUTPUT WAVEGUIDE OF THE AMPLIFIER WITH AN
RF LOAD CAPABLE OF DISSIPATING FULL CW RF POWER. SIMILARLY
TERMINATE THE INPUT TO AVOID THE POSSIBILITY OF THE AMPLIFIER
BEING DRIVEN BY STRAY LEAKAGE SIGNALS. Incorporate the termination prior to
applying prime power to the amplifier. This procedure prevents self-oscillation and irradiation of
the local environment. Even if a source is not connected to the amplifier you are working with,
there are situations where the amplifier can go into a self-induced mode and generate high levels
of RF energy. Destruction caused under excessive load voltage standing wave ratio (VSWR) will
void the warranty. Although the equipment has internal protection for VSWR higher than 3:1
and will automatically go in shutdown (with a delay of 1 second), still it is a safe procedure to
avoid unwanted effects.

AWMA-C250
Page 8
----------------------------------------------- WARNING ----------------------------------------------------
DO NOT LOOK INTO THE OUTPUT PORT OF THE POWERED RF AMPLIFIER.
Treat the powered amplifier with extreme care. Keep in mind that levels of microwave radiation
that do not induce immediate physical discomfort in most individuals can be sufficiently high to
induce longer term effects. Your eyes are particularly vulnerable parts of your body.
The permissible levels of exposure are quite low in comparison to the power levels of the
amplifiers built by Advantech (e.g. less than 10 mW versus 20 to 1000 W delivered by different
units). The permissible levels are currently being studied by a number of organizations. In the
past the U.S. safety Code established a dosage rate of 10 mW/cm2. Currently there is
consideration being given to reducing the permissible level to 1 mW/cm2in the United States, as
has been the case for several European countries.
----------------------------------------------- CAUTION -----------------------------------------------------
TWO OR MORE PEOPLE SHOULD BE LIFTING AND MOVING this equipment or use
an equipment cart. There is a risk of back injury, if carried by a single person.

AWMA-C250
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2. GENERALINFORMATION
This manual contains information that describes installation, operation, and maintenance
procedures for the REDUNDANT 1:1 SYSTEM 250 W C-Band hub-mount (outdoor) Solid
State Power Amplifier (SSPA) model AWMA-C250. Because specialized training is required for
some phases of installation and operation, certain parts of this manual are directed only to trained
personnel. Warnings appear at the appropriate points to caution all users against potential RF and
high-voltage hazards.
For a safe and versatile operation, please read this information carefully BEFORE using the
equipment.
Advantech Advanced Microwave Technologies, Inc. has prepared this manual for use by
Advantech personnel and customers as a guide for the proper installation, operation and
maintenance of Advantech equipment and computer programs. The drawings, specifications and
information contained herein are property of Advantech Advanced Microwave Technologies,
Inc. Any unauthorized use or disclosure of these drawings, specifications and information is
prohibited; they shall not be reproduced, copied or used in whole or in part as the basis for
manufacturing or sale of the equipment or software programs without the prior written consent
of Advantech Advanced Microwave Technologies, Inc.

AWMA-C250
Page 10
Figure 1: Product Outline
Redundant 1:1 System, mounted on Redundancy Frame

AWMA-C250
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Figure 2: Product Outline (each unit)
INPUTCURRENT
INPUTVOLTAGE
REV.S/N
FREQUENCY
RFOUTPUTPOWER
MODEL
P/N
BAND
W
MFG
GAINmin.
dB
dBm
GHz
A
V

AWMA-C250
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ISOLATOR
J1
RF
INPUT
J4
OUTPUT
MONITOR
J7
W/G OUTPUT
COOLING
FAN
J5
AC
L
INE
220 VAC
- 9V
COMMON
PMALARM
TEMP
MUTE
+ 12V
(high current)
A
B
C
TH
+ 12V
+ 15V
MONITOR & CONTROL
SPEED
CONTROL
POWER
SUPPLY 1
DRIVER ASSEMBLY
LPA
TEMP.
SENSOR
+12V,
-9V
+ 15V- 9V
TEMP.
COMP.
POWER CONDITIONER
BOARD ASSEMBLY POWER CONDITIONER
BOARD ASSEMBLY
+12V,
-9V
30 dB
TH
OUTPUT WAVEGUIDE
ARM ASSEMBLY
OUTPUT
POWER
DETECTOR REFLECTED
POWER
DETECTOR
ISOLATOR
FILTER
20 dB
40 dB
TEMP.
SENSOR
POWER MODULE ASSEMBLY
HPA
POWER
SUPPLY 2
+ 15V
LINE
FILTER
- 15V
+ 5V
COM
J2
SERIAL
I/F
J3
DISCRETE
I/F
J6
REDUNDANT
I/F
CURRENT
SENSOR
CURR
PULSE
220 V
DALARM
MUTE-D
DTEMP
GAIN
DALARM
MUTE-D
DTEMP
GAIN
+ 15V
+ 15V
- 15V - 15V
+ 5V + 5V
- 9V
- 9V
PS1FAIL PS2FAIL PS2FAIL
PS1FAIL
+ 12V
+ 12V
+ 12V + 12V
Figure 3: Block Diagram (one unit)

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3. MAJOR SUBSYSTEMS AND THEIR FUNCTIONS
The Redundant 1:1 System contains 2 Solid State Power Amplifiers (SSPA) model
AWMA-C250 mounted on a redundancy frame and interconnected via dedicated harnesses,
waveguides, semi-rigid coaxial cables and waveguide switch. The entire system is intended for
mounting near the hub of the antenna or behind the antenna as part of the balance weight
(outdoor applications).
Each unit incorporates two DC main power supplies and cooling by forced air; also, each unit
features an embedded micro-controller for monitoring and supervising of all major parameters.
Remote/Local control from a computer via an RS-422/485 Serial Interface, as well as control via
the Discrete Interface is available.
Both units are pre-loaded with 1:1, cold STANDBY software versions and fully active through
the Redundant Interfaces (J6).
3.1 RF SUB-SYSTEM
The RF subsystem contains 2 high power Solid State Power Amplifiers model
AWMA-C250 in a redundant 1:1 configuration. This option is available as a field upgradable
option and it is implemented by loading the required operating software, via the serial
communication link (port J2) of each unit.
In a 1:1 Redundant Operation, one amplifier is on-line and the other one is in STANDBY state
(connected to a dummy load). The STANDBY unit is in MUTE (sleep) mode, if the system is in
AUTO mode of operation, and in full power mode if the system is in MANUAL mode of
operation. The basic configuration of the 1:1 Redundant System is shown in Figure 5 at page 16.
When the unit A is on-line the unit B is in standby and vice versa. Both units are capable of
completely meeting all RF performance specifications within thirty minutes of application of the
prime power.
3.1.1 RF HIGH POWER MODULE
Each unit has an RF High Power Module that consists of a 250 W Solid State Power Amplifier
operating over the frequency range of 5.850 – 6.425 GHz. A DC board containing the bias,
control and protection circuitry is included in this module. The module is integrated on a heat
sink and provides an interface for Monitor and Control board.
3.1.2 RF DRIVER MODULE
Each unit has an RF Driver Module that consists of a Solid State Power Amplifier operating over
the frequency range of 5.850 – 6.425 GHz. The driver module is integrated on a heat sink and
provides an interface for Monitor and Control Board. This module has a DC board containing the
bias, control and protection circuitry. Other features include temperature compensation, gain
control & Summary Alarm Indication (failure report of one or more GaAs devices).

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3.1.3 WAVEGUIDE ARM ASSEMBLY
The Waveguide Arm Assembly of each unit includes a harmonic filter, a three-port output
circulator and related power detectors (for Forward Power and for Reflected Power).
• The output circulator provides one reflected power port coupled via a detector to the Monitor
and Control board for reverse power protection. The output port of the waveguide arm
assembly has a minimum 20 dB output return loss and the output flange is CPR-137 G
(grooved).
• One extra sample port, the RF Output Monitor Port, calibrated in coupling ratio versus
frequency, permits the independent monitoring of SSPA output power levels via an ‘N’ type
connector on the connectors plate, by using a portable power meter or an external spectrum
analyzer.
3.1.4 RF INPUT ISOLATION CIRCUIT
The RF Input Isolation Circuit of each unit provides a minimum Input Return Loss of 18 dB over
full frequency band at the N-type RF input connector of the SSPA.
3.2 THE REDUNDANT WAVEGUIDE SWITCH ASSEMBLY
The redundant waveguide switch assembly consists of a W/G Switch and the required
waveguides and a dummy load. Both units have control over the switch based on a scale of
priorities. During traffic the RF output of a faulty unit will be transferred to a dummy load.
3.3 THE REDUNDANT FRAME ASSEMBLY
The Redundant Frame Assembly consists of a metallic structure designed to withstand the entire
system and to confer strength and stability, as usually required in outdoor applications. Delivery
of different parts of the redundant frame assembly allows for the following options:
- Option A: vertical mounting frame;
- Option B: “A”–shaped support frames ( 2 pieces);
- Option C: Base asymmetrical frame;
- Option D: all of the above.

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Figure 4: Connectors side of one unit
TABLE 1: CONNECTORS (each unit)
Connector Function Description Mating Connector
(J1) RF Input N - Type (F) N - Type (M)
(J2) Serial Interface MS3114E10-6P (M) MS3116F10-6S (F)
(J3) Discrete Interface MS3114E16-26P (M) MS3116F16-26S (F)
(J4) RF Output Monitor Port N - Type (F) N - Type (M)
(J5) AC Line MS3102R20-19P (M) MS3106F20-19S (F)
(J6) Redundant Interface MS3112E14-12P (M) MS3116F14-12S (F)
(J7) RF Output CPR-137G (Grooved) CPR-137F (Flat)

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AMPLIFIER "A"
J1 J7
J2 J6
AMPLIFIER "B"
J1 J7
J2 J6
SPLITTER
RS-485
RF INPUT
(TYPE N, FEMALE)
RF
INPUT B
RF
INPUT A
RF OUT B
RF OUT A
TO
ANTENNA
COAXIAL
SWITCH
REDUNDANT
I/F B
W/G LOAD
REDUNDANT
I/F A
SERIAL
I/F A
SERIAL
I/F B
W/G
W/G
SERIAL I/F
CABLE REDUNDANT I/F
CABLE
TO PC
HIGH POWER
SSPA
HIGH POWER
SSPA
Figure 5: Block Diagram 1:1 Redundant System

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3.4 POWER SUPPLY SUBSYSTEM
The Power Supply of each unit consists of two identical, 1200 W Power Supply modules. Each
module can supply outputs as follows:
• 3 x 30 A @ + 12V DC,
• 3 x 0.1 A @ - 9V DC,
• 2 x 0.125 A @ +20V DC,
• 1 x 0.3 A @ +15V DC,
• 1 x 0.100 A @ - 15V DC,
• 1 x 0.5 A @ +5V DC
The power supply portion of the SSPA provides all of the internal voltages necessary to operate
the RF section and the Monitor and Control board. Both power supply modules and the cooling
fan are configured for 220 VAC. The overall power consumption at rated RF output power is
typically 2000 W for one unit.
TABLE 2: AC LINE (J5) – PIN ASSIGNMENTS (each unit)
Pin Description
A PHASE (LIVE)
B GROUND
C NEUTRAL
3.5 MONITOR AND CONTROL BOARD
The Monitor and Control Board provides:
• Status indicator via open collector output: Fault, Alarm, Remote Control, RF Output higher
than threshold level and RF Mute.
• Gain control function for power amplifier gain adjustment.
• Communication with the long line customer (discrete) interface for monitoring all above
mentioned conditions.
• Communication with a Personal Computer (PC) via the serial interface.
The Monitor and Control board is connected to major components of the SSPA and to the
customer (discrete) interface. All controls, input/output and decision-making, with the exception
of critical module level decisions, are done by the Monitor and Control module.

AWMA-C250
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3.6 THE COOLING SUBSYSTEM
The cooling subsystem of each unit includes the Fan and the harnesses provided for easy fan
replacement. The cooling fan is configured for 220 VAC operation (pulsed controlled by a speed
control PCB, which allows for a temperature dependent rotating speed).
3.7 LRU PHILOSOPHY
The maintenance concept employed in each unit is to localize a malfunction or circuit failure
down to the level of an LRU (Line Replaceable Unit), extract the LRU and replace it with an
equivalent part provided in the spare kit. This procedure can be completed in the field, without
resorting to the costly practice of returning the entire system to the depot for servicing. The
philosophy is to configure the LRUs as building blocks with a specific function that can be
monitored by sensors and fault indicators on a real-time basis.
Each unit contains circuitry to protect itself from operational damage caused by abnormal AC,
DC, RF faults or insufficient cooling.

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Page 19
4. UNPACKINGAND INSTALLATION
This section contains instructions for site preparation, unpacking and installation of the units.
4.1 INITIAL INSPECTION
Inspect the shipping container for damage. If the container or cushioning material is damaged,
immediately contact the carrier that delivered the equipment and submit a damage report. Failure
to do so could invalidate future claims.
4.2 UNPACKING
Carefully unpack and remove all items (inspect the interior of the container for damage). Save all
packing material until all inspections are complete. Verify that all items listed on the packing list
have been received. Inspect all items for evidence of damage in shipment. If damage seems
evident, immediately contact the carrier that delivered the equipment and file a claim. Failure to
do so could invalidate future claims. Check the units thoroughly for damaged or loose parts.
After visual inspection is complete, proceed to the next step.
4.3 INSTALLATION
Installation of the SSPA includes four phases:
• Mechanical installation
• Electrical installation
• RF connections
• Cooling considerations
4.3.1 MECHANICAL INSTALLATION
Refer to Figure 6 at page 20. Put the base frame of optional “A” frame or redundancy frame,
made of two sections of unequal widths, on floor. Make sure that the larger section is on front
side. Central beam of the base frame has five stand-offs. On these stand-offs install the vertical
mounting frame (hardware provided). This vertical frame has six stand-offs that should be on top
and facing front. On the sides of base frame, install two supporting frames (‘A’ shaped) each
bolting at four places to base frame and three places to the vertical mounting frame (hardware
provided). Tighten all bolts, so that the vertical mounting frame and the two ‘A’ shaped frames
are vertically placed relative to the base frame.
This mechanical assembly can be installed on site, at ground level or at the tower level. To
reduce vibration due to wind and fans, as well as for safety reasons, it is highly recommended to
bolt down this assembly. 16 holes @ 5/8” diameter are provided on the base frame for this
purpose only.