CPI VZC-6967AD User manual

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Commllnication.J& Pov.-er Jndustrie:r
satcorn ~division
Formerly Varian Associates, Incorporated
Microwave Equipment Products
811 Hansen Way
Palo Alto,
CA 94303
CPI #01023245 REV. 9
Model No.
VZC-6967AD
VZC-6967AB
VZC-6967AG
VZU-6997AC
VZU-6996AB
VZU-6996AC
VZU-6997AE
VZU-6997AG
VZU-6995AY
VZU-6967AA

PROPRIETARY INFORMATION
The design and other information contained in this document are provided
solely for the purposes of operating and maintaining CPI equipment. Except
for rights expressly granted
by contract, all such information is the exclusive
property of CPI Satcom Division. This document may not be duplicated, in
whole or in part, or be used for manufacture without written permission of
CPi, Satcom Division.
Copyright © 1999 by Communications & Power Industries.
All rights reserved.

CMPA SERIES
CONTENTS
SECTION S: SAFETY
High-Voltage Equipment Personnel
Operating Guidelines ............................................................................................................. S-3
When is Voltage "High"? ............................................................................................ S-3
General Guidelines ....................................................................................................... S-4
Microwave Radiation Personnel Operating Guidelines ............................................... S-8
Discussion ....................................................................................................................... S-8
General Guidelines ....................................................................................................... S-9
SECTION 1: INTRODUCTION
About This Manual .................................................................................................................. 1-2
Major Subsystems and Their Functions............................................................................. 1-3
Technical Description ............................................................................................................. 1-5
RF Subsystem .................................................................................................................1-4
Power Supply Subsystem ............................................................................................
1-9
Power Factor Correction Module ............................................................................. 1-9
Power Processor Module ......................................................................................... 1-1 0
High-Voltage
Module ................................................................................................ 1-1 0
RF Power Monitor Module ...................................................................................... 1-10
Control and Display Modules.................................................................................... 1-1
LRU Philosophy ..................................................................................................................... 1-12
Optional Features ................................................................................................................. 1-12
SECTION 2: UNPACKING AND INSTALLATION
Pre-Inspection ........................................................................................................................... 2-1
Unpacking .................................................................................................................................. 2-1
Preparing for Installation........................................................................................................ 2-2
Installation .................................................................................................................................. 2-2
Mechanical Installation ................................................................................................ 2-3
Electrical Connections.................................................................................................. 2-3
Prime Power Grounding .............................................................................................2-4
CPI # 01023245
REV. 9
MAY 17, 1999
Ill

CONTENTS
1/0 Interfaces .................................................................................................................2-5
RF Connections..............................................................................................................2-5
RF Output (Waveguide Connection) ......................................................................2-6
Cooling Considerations ...............................................................................................2-7
SECTION 3: INTERFACES
CMPA Control Mode Hierarchy..........................................................................................3-2
Serial Remote Interface..........................................................................................................3-2
RF Switch System Interface...................................................................................................3-6
Relay Definitions ...........................................................................................................3-6
External Interlocks Interface..................................................................................................3-9
Computer Interface.............................................................................................................. 3-10
CIF Hardware Configuration................................................................................... 3-11
Computer Interface (CIF) Protocol .................................................................................. 3-12
Protocol Message Structure .................................................................................... 3-13
Command and Response Format.......................................................................... 3-14
Header and Ending Bytes ......................................................................... 3-15
Adress Bytes................................................................................................. 3-16
Command Bytes ......................................................................................... 3-16
Response Bytes ........................................................................................... 3-16
Reject Bytes.................................................................................................. 3-16
Check Bytes.................................................................................................. 3-1 7
Carriage Returns & Line Feeds ............................................................... 3-18
Commands .............................................................................................................................. 3-19
Slow Commands......................................................................................... 3-24
Status Byte Definitions ........................................................................................................ 3-24
ID/Version Message ............................................................................................................ 3-30
IV MAY 17, 1999
CPI # 01023245 REV. 9

CMPA SERIES
SECTION 4: INITIAL POWER-ON AND CHECKOUT
Pre-Power Procedures ............................................................................................................ 4-1
Using the Front Panel ............................................................................................................. 4-3
Initial Power-On Procedures................................................................................................. 4-3
Power-On Self-Test and Heater Time Delay.......................................................... 4-4
Verifying Operational Settings ............................................................................................. 4-5
Setting the Fault and Alarm Trip Points............................................................................. 4-5
Setting Serial Remote and CIF Port Parameters ............................................................. 4-8
Verifying RF Output Level .....................................................................................................4-9
Verifying RF Alarm and RF Fault Trip Points....................................................... 4-11
Testing the CMPA via Computer Control ..................................................................... 4-12
Testing Optional Equipment.............................................................................................. 4-13
Re1note Control Interface ........................................................................................ 4-13
SECTION 5: OPERATION
Essential CMPA Operating Procedures............................................................................. 5-2
Transmit ........................................................................................................................... 5-2
Normal Shutoff............................................................................................................... 5-3
Basic Ci\1\PA Operation .......................................................................................................... 5-3
CMPA States and Description .............................................................................................5-4
Initialization and Power-On Self-Test (POST) State ............................................. 5-5
Heater Time Delay (HTD) State................................................................................ 5-7
Standby State .................................................................................................................. 5-8
Transmit State................................................................................................................. 5-9
Fault State ..................................................................................................................... 5-10
CMPA Control Modes and Hierarchy............................................................................. 5-11
RF Control Modes ...................................................................................................... 5-12
Special CMPA Functions..................................................................................................... 5-13
Factory Authorized Access Mode ......................................................................... 5-13
Terminology ................................................................................................................. 5-13
Exiting a Menu ............................................................................................................ 5-14
Data Entry Rules ......................................................................................................... 5-14
Quick Access Codes ............................................................................................................ 5-17
CPI # 01023245 REV. 9
MAY 17. 1999 v

CONTENTS
SECTION 6: MAINTENANCE
Introduction ............................................................................................................................... 6-1
Scheduled Preventive Maintenance ................................................................................... 6-2
Mechanical Preventive Maintenance ................................................................................. 6-2
Visual Inspection ........................................................................................................... 6-5
Inspecting & Cleaning Air Filters...............................................................................6-6
Checking A3
LEOs & Display ..................................................................................... 3-6
Collector Air System Maintenance .......................................................................... 6-6
Checking Rear Cooling Fan and Collector Fan .................................................... 6-6
Miscellaneous Cleaning...............................................................................................6-7
Electrical Preventive Maintenance ......................................................................................6-7
Spare TWT Maintenance ............................................................................................6-8
Performance Testing ...............................................................................................................6-9
Power and Gain ..........................................................................................................
6-1 0
SECTION 7: DRAWINGS AND SCHEMATICS
SECTION
8: SUPPLEMENTARY DATA
APPENDIX
A: SPECIFICATIONS
APPENDIX
B: CONTROL APPEARANCE AND CONTENT
Buttons........................................................................................................................................ B-1
LEOs ............................................................................................................................................. B-3
Beeper......................................................................................................................................... B-3
Alphanumeric Display Definition ........................................................................................ B-4
Meters............................................................................................................................... B-6
Fault Messages That Correspond to Digital Status Lines .................................. B-7
Fault Messages Generated by Limit Comparisons .............................................. B-8
Alarms............................................................................................................................... B-9
General Status Screens ............................................................................................. B-1 0
Control Menu ......................................................................................................................... B-11
Data Entry Rules ......................................................................................................... B-12
Categories .................................................................................................................... B-16
VI MAY 17, 1999
CPI # 01023245 REV. 9

CMPA SERIES
Linearizer Control ...................................................................................................... B-19
Linearizer
Adjustment ............................................................................................... B-19
RF Trip Limits/Switch Port Relay Settings............................................................ B-21
Fault Log........................................................................................................................ B-24
FAAC ..............................................................................................................................
B-25
Fault Trip Setting......................................................................................................... B-26
Factory Tests ................................................................................................................ B-26
Reset Elapsed Time
Meter ....................................................................................... B-27
Reset To Factory Defaults........................................................................................
B-2 7
CMPA HVPS Test Mode .......................................................................................... B-27
User Tests ..................................................................................................................... B-28
Time/Date .................................................................................................................... B-29
RemotejCo1nputer Interface...................................................................................
B-31
Software Versions ...................................................................................................... B-34
Elapsed Hours Information ......................................................................................
B-35
Quick Access Codes ............................................................................................................ B-36
POST Faults ............................................................................................................................ B-38
Software Error Codes........................................................................................................... B-39
Flash RAM- Operating and Programming...................................................................... B-39
To Force the
CMPA to use EPROM Contents ............................................................. B-40
Reprogramming the
Flash RAM ....................................................................................... B-40
Troubleshooting and Error messages Associated
with the Flash RAM ................. B-42
APPENDIX C: REPLACEABLE PARTS
APPENDIX
D: WARRANTY/SUPPORT INFORMATION
Return Procedure .................................................................................................................... D-1
APPENDIX E: OPTIONS AND FEATURES
CPI # 01023245 REV. 9
MAY 17, 1999 VII

CONTENTS
LIST OF FIGURES
Figure 1-1 The CMPA ............................................................................................................. 1-3
Figure 1-2 CMPA RF Diagram (Ku-band shown) ............................................................ 1-4
Figure
1-3 Power Supply Block Diagram .......................................................................... 1-8
Figure
2-1 Rear Panel of CMPA ........................................................................................... 2-3
Figure 3-1 Setting Termination Resistors .......................................................................... 3-3
Figure 3-2 Setting Serial Format...........................................................................................3-9
Figure
4-1 CMPA Front Panel ...............................................................................................4-2
Figure
5-1 Control Panel ........................................................................................................ 5-1
Figure 5-3 Example: Accessing CMPA Features .......................................................... 5-14
Figure
6-1 TWT Amplifier Test Setup .............................................................................. 6-12
Figure
B-1 Front Panel Picture .............................................................................................. B-1
VIII MAY 17. 1999
CPI # 01023245 REV. 9

CMPA SERIES
LIST OFT ABLES
Table 3-1 Serial Remote Interface Pin Assignment (J6) ................................................ 3-5
Table 3-2 Low RF Relay Function ........................................................................................3-7
Table 3-3
RF Switch Pin Assignment (JS) ..........................................................................3-8
Table 3-4 Interlocks Interface
Pin Assignment (J8) ..................................................... 3-10
Table 3-5 CIF (Computer Interface)
Pin Assignment (J7) .......................................... 3-12
Table 3-6 Reject Bytes ......................................................................................................... 3-17
Table 3-7
Query Commands ............................................................................................ 3-20
Table 3-8
CMPA Commands............................................................................................. 3-22
Table 3-9 Slow Commands ................................................................................................ 3-24
Table 3-10 Interface Commands ...................................................................................... 3-24
Table 3-11 Summary Status Bytes .................................................................................... 3-25
Table 3-12 Secondary Status Bytes .................................................................................. 3-27
Table 3-13 Fault and Miscellaneous Status ................................................................... 3-28
Table 3-14 Information/Error Messages ......................................................................... 3-30
Table
4-1 Helix and RF Settings Ranges ............................................................................4-7
Table
5-1 Front Panel Categories ..................................................................................... 5-15
Table
6-1 Preventative Maintenance Schedule ............................................................... 6-3
Table 6-2 Recommended Test Equipment........................................................................ 6-4
Table 6-3
CMPA Performance Data Log........................................................................ 6-11
Table 7-1 Compact MPA Drawings.................................................................................... 7-1
Table A-1 Electrical Specifications-C-Band ..................................................................... A-2
Table A-2 Electrical Specifications-X-Band ..................................................................... A-4
Table A-3 Electrical Specifications-Ku-Band ................................................................... A-6
Table A-4 Additional Specifications
for CMPA ............................................................... A-8
Table
B-1 Front Panel Button Description ........................................................................ B-1
Table B-2 Front Panel LEOs ................................................................................................... B-3
Table B-3 Front Panel Categories ..................................................................................... B-1 0
Table
B-4 Default Values for User Features .................................................................. B-12
Table
B-5 RF Display Preferences .................................................................................... B-14
Table
B-6 RF Alarms and Faults......................................................................................... B-1 7
Table
B-7 Fault/ Alarm Settings......................................................................................... B-19
Table
B-8 Fault Trip Settings .............................................................................................. B-22
CPI # 01023245 REV. 9
MAY 17, 1999 IX

CONTENTS
Table B-9 User Tests and Results ..................................................................................... B-29
Table
B-1 0 Time/ Date Settings ........................................................................................ B-30
Table
B-11 Computer Interface Parameters.................................................................. B-32
Table B-12 Software Versions ...........................................................................................
B-33
Table B-13 Elapsed Hours Feature ................................................................................... B-35
Table B-14 Post Faults.......................................................................................................... B-38
Table B-15 Software Error Codes .....................................................................................
B-3 9
X
MAY 17, 1999
CPI # 01023245 REV. 9

Section S
Safety

SECTIONS
SAFETY
Symbols
[>INGERaJS
vct.TAGE
ATTENTION
CPI # 01023245 REV. 9
CMPA SERIES
In addition to the "High Voltage Equipment Personnel Operating Guidelines"
and
the" Microwave Radiation Personnel Operating Guidelines" given in 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 TRANSMITIING EQUIPMENT",
and also Sub-clauses 3.2,
3. 7, and 22.1 of the Standard.
Black lightening
bolt in black triangle outline on yellow background.
Description: Caution, risk
of Electrical Stock.
Black exclamation point in black triangle outline on yellow background.
Description: Caution (Refer to accompanyingdocuments).
MAY 17, 1999

SAFETY
S-2
MAY17,1999
CPI # 01023245 REV. 9

CMPA SERIES
HIGH VOLTAGE EQUIPMENT PERSONNEL OPERATING
GUIDELINES
INTRODUCTION
This guideline document presents operating practices for operators and
technicians
who work with high voltage equipment. In the context of this
discussion any voltage that
is lethal is viewed as "high voltage". Therefore,
even
prime power (115 to 440 VA C) is dangerous because prime power
potentials have been known to cause death or injury.
Electrical circuits operate quickly and
do not allow a careless individual a
second chance.
When dealing with high voltage, the results are very
consistent and predictable and hazards associated
with high voltage are
always present. THE FACT THAT THE
CONTROL SWITCH SAYS OFF
DOES
NOT MEAN YOU ARE SAFE. Many high voltage circuits are like
loaded guns. IN GENERAL,
YOU CANNOT SEE A HIGH VOLTAGE
HAZARD. You can learn to recognize situations that present athreat and
how to avoid them.
NOTE:
The guidelines presented in this guide are not academic. They are based on the
experience of engineers and technicians who have years of experience with high
voltage circuits.
WHEN IS VOLTAGE "HIGH"?
CPI # 01023245 REV. 9
As stated earlier, any voltage that will kill you should be treated as "high
voltage". Voltages associated
with prime power generally do not jump the
air gap
between people and the equipment. Usually exposed circuit
elements such
as a terminal, bare piece of wire, or some non-insulated
surface
must be touched. One of the problems associated with prime
power is some equipment can be "floating" above ground. In this case, if
you place one hand on the equipment chassis and the other on earth ground
you can
be jolted, injured or killed. 440 VAC can stimulate an involuntary
muscle response that will either literally
throw you across a room or seize
and
hold you across the voltage terminals. 600 or more volts can hold you
indefinitely.
If the potential is sufficient to drive 200 milliamps through your
body you will be held indefinitely. Some people consider the 200 to 600
volt range to be worse than potentials of thousands of volts.
MAY17,1999 S-3

SAFETY
GENERAL GUIDELINES
S-4 MAY 17. 1999
NOTE:
In addition to the above, the following practices have proven effective for
personnel who deal with high voltage equipment.
a. HANDS OFF. Avoid contact with any potential source of high voltage.
Keep hands
out of the equipment when it is operating.
b. AVOID ACCIDENTAL CONTACT. Make sure that some other part of
your body does not come in contact with the high voltage circuits. It is
easy to forget the hazards when you are concentrating on a frustrating
or interesting task. Pens and badges in shirt pockets could cause
contact.
c. NEVER WORK ON HIGH VOLTAGE CIRCUITS WHEN YOU ARE
ALONE. If anything should happen to you, your only chance may be
prompt action by some other person. Be sure someone else is present
and knows
what to do in an emergency. (e.g .. how to shut equipment
off, first aid, who to call, etc.)
d. USE ONE HAND WHEN WORKING WITH HIGH VOLTAGE CIR-
CUITS.
Many people recommend that you put one hand in your
pocket when you use a probe or other piece of equipment inside a
high voltage section.
e. DO NOT FLOAT MEASURING EQUIPMENT ABOVE GROUND.
Make all measurement with respect to ground. The odds are that if
you float the instrument, you may forget and reach inside the equip-
ment. Although
it is harder to get the right test setup, it is well worth
the effort.
f.
DO NOT ASSUME THAT THE LEVEL OF RISK IS A FUNCTION OF
SIZE. Some large high power voltage equipment looks docile. One
reason the equipment is so big is to get the proper separation between
high voltage points. On the other hand, just because the equipment is
small is no assurance of safety. Dense packaging results in more
difficultaccess and increases the chance that you will accidentally hit
the wrong point.
g. ALWAYS DISCHARGE HIGH VOLTAGE CAPACITORS. High voltage
capacitors store a
lot of energy for long periods of time. High voltage
capacitors also
exhibit a "memory" in that they can recover after
discharge and reach lethal levels.
In addition to the "memory" prob-
lem, there have been instances where the built-in safety features have
failed
or been miswired. Each and every time you go to work on a
piece
of high voltage equipment use a grounding rod with a long
handle to discharge every high voltage capacitor.
CPI # 01023245 REV. 9

CPI # 01023245 REV. 9
CMPA SERIES
h. DO NOT DEPEND ON THE AUTOMATIC FEATURES OF THE
EQUIPMENT TO SAVE YOU. You never know when someone has
left a circuit disabled, or if there has been a wiring error, or if a compo-
nent has failed.
i. TAKE PERSONAL RESPONSIBILITY TO ASSURE THAT NO ONE
CAN TURN ON THE HIGH VOLTAGE CIRCUITS WHEN YOU ARE
WORKING ON THE EQUIPMENT. Precautions would include taping
down (or installing keeper) on controls/circuit breakers and/or discon-
necting the
power source to the high voltage circuits, activating
interlocks that prevent high voltage turn on, etc.
Know where the
disconnects are and use them.
Do not rely on anyone not to turn on
the high voltage.
j.
SET UP YOUR TEST EQUIPMENT WITH THE POWER OFF. Conduct
the power-on operations when you have your hands out of the equip-
ment.
k. DO NOT USE SHORT PROBES FOR HIGH VOLTAGE MEASURE-
MENTS. A short
probe does not allow any margin for error. If your
hand slips you could accidentally come into contact with a danger
point. A
long probe avoids the whole problem.
READ THE INSTRUCTION
MANUAL The best insurance is fore-
knowledge
of hazards.
m.
CREATE A FAVORABLE ENVIRONMENT FOR SAFE OPERATIONS.
This means that
if people are crowding you, stop the operation ifit
involves high voltage. Pressure can lead to carelessness. In the same
way, fatigue
is also an enemy. STAY ALERT AT ALL TIMES WHEN
WORKING WITH HIGH VOLTAGE.
n. DO NOT BECOME OVER CONFIDENT. Maintain a healthy respect
for high voltage.
o. A
GOOD OPERATING PRACTICE IS TO CHECK THE POTENTIAL
BETWEEN THE
EQUIPMENT CHASSIS AND EARTH GROUND
BEFORE YOU COMPLETE THE CIRCUIT WITH YOUR BODY. As
voltage levels increase, the protection you get from insulation and air
gap diminishes. For example, in a piece
of equipment that involves
beam voltages
of about 16 KV, the beam transformers look very safe
with massive insulation on the outside of the coils. Physical contact
with the beam coil when the system is operating can be fatal. Al-
though the
equipment is placard to warn people of the presence of
high voltage, it is virtually impossible to placard every point of danger in
a system.
MAY17,1999

S-6 MAY17,1999
SAFETY
p. IF YOU DO NOT KNOW HOW THE EQUIPMENT WORKS AND
WHAT THE HAZARDS ASSOCIATED WITH THE EQUIPMENT ARE
IN SPECIFIC TERMS, DO NOT HANDlE THE EQUIPMENT. The
greatest protection you can have when dealing with high voltage
equipment
is specific, detailed knowledge on that particular piece of
equipment.
q. AVOID 'HAYWIRE' TEST SETUPS. It is easy to get in trouble if the
setup you are using has a jumble
of wires.
r. MAKE SURE YOUR CONNECTIONS ARE SECURE. Do not allow
leads to
slip off and move about in an uncontrolled fashion. Even if it is
not one of the high voltage leads, a free lead could (and generally
does) move exactly to where you
do not want it. The only safe
connection is amechanically secure one.
s. WATCH OUT FOR UNTERMINATED HIGH VOLTAGE LEADS. Some
connectors
depend on circuit loading to avoid arcing between closely
spaced terminals. Unloaded high voltage lines or plugs can lead to
arcing situations.
t. SHUT OFF THE HIGH VOLTAGE WHEN YOU ARE MAKING LOW
VOLTAGE MEASUREMENTS. Its does not make any sense to increase
danger needlessly. While there may
be times when you cannot shut
off the high voltage during a low voltage measurement this
is generally
not the case.
u. REMOVE THE TEST EQUIPMENT WHEN YOU HAVE FINISHED A
MEASUREMENT PROGRAM. There have been many instruments
destroyed or
damaged because a test program was conducted in a
haphazard manner rather than
in an orderly progression from start to
finish. Experience has shown many instances when a little order would
have prevented a tragedy or avoided an expensive mistake.
v. BE EXTREMELYWARYWHEN MAKING FILAMENT VOLTAGE
MEASUREMENTS. The cathode of tubes is elevated above ( or below)
ground and the filament voltages usually
cannot be measured with
reference to ground. Do everything you can to assure that the high
voltage
cannot be turned on when you are making your measurements.
This includes disconnecting the high voltage drive source, shorting out
appropriate leads, taping down switches and anything else you can
think ofto protect yourself.
w. WHEN TROUBLE SHOOTING A UNIT ASSUME THAT THE
SWITCHES AND COMPONENTS ARE DEFECTIVE. You may shut off
the high voltage switch
in some systems, but if the switch is defective
you would
still have the high voltage on. Returned units are potential
boobytraps.
CPI # 01 023245 REV. 9

CPI # 01023245 REV. 9
CMPA SERIES
x. MAKE SURE THAT YOUR WORK STATION IS STABLE. Flimsy work
surfaces or supports for the equipment or the test instruments repre-
sent a real threat.
Do not use a setup that you know is unstable and/or
dangerous.
y. USE THE 30 SECOND RULE. Wait 30 seconds after you have shut off
the equipment before you work on a unit. Part of the reason for the
30 second rule is that some of the dielectrics (insulators) used for high
voltage circuits can store a charge. While the amount of charge stored
is a function of the size of the object, the 30 second rule provides an
additional margin
of safety.
z. MAINTAIN A HEALTHY RESPECT FOR ANY KIND OF LIVE CIR-
CUITS. COMPLACENCY CAN HURT YOU OR KILL YOU. Your
continued wariness is your bestinsuranceagainst injury or death.
MAY 17,1999 S-7

SAFETY
MICROWAVE RADIATION PERSONNEL OPERATING GUIDELINES
INTRODUCTION
DISCUSSION
S-8 MAY 17, 1999
This guideline document presents operating practices appropriate for
operators and technicians
who work with equipment involving microwave
radiation. Keep in mind that levels of microwave radiation that do not
induce immediate physical discomfortin most individuals can be sufficiently
high to
induce longer term effects. CPI Satcom Division Equipment usually
is related to amplification of an RF signal from an external source. 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. This condition can exist if the unit is operated
with high voltage on and without proper termination on the input and output
of the amplifier.
Protect yourself and those around you from unwanted RF exposure. Always
terminate the amplifier input and output with an RF dummy load before you turn
the high voltage on. This will reduce the chances of oscillation due to internal
amplifier noise.
Limitexposure to microwave radiation to prevent unwanted biological
effects. There are
other effects that can lead to problems if you are careless
in
operating or servicing microwave equipment. The permissible levels are
quite low in comparison to the power levels of the amplifiers built by CPl.
(e.g.
less than 10 milliwatts vs 20 to 10,000 watts delivered by different
units). Local radiation levels can
be detected with the proper equipment.
The permissible levels are currently being studied
by a number of
organizations. In the past the U.S. Safety Codes established a dosage rate
of 10 mw/cm. sq. Currently there is consideration being given to reducing
the permissible level
to 1 mw/cm. sq. in the United States as has been the
case
for several European countries.
CPI # 01023245 REV. 9

CMPA SERIES
GENERAL GUIDELINES
The purpose of these guidelines is to provide practical approaches to control
unwanted
microwave energy associated with the operation and servicing of
CPI Satcom Division equipment. The following approaches are effective in
bothlaboratory
or field environments.
a. ALWAYS TERMINATE THE OUTPUT WAVEGUIDE OR CONNEGOR
WITH A DUMMY RF LOAD (CAPABLE OF DISSIPATING FULL CW
RF POWER). SIMILARLY, TERMINATE THE INPUT TO AVOID THE
POSSIBILITY
OF THE AMPLIFIER BEING DRIVEN BY STRAY LEAK·
AGE SIGNALS. Incorporate the terminations prior to applying prime
power to the amplifier. This procedure prevents self oscillation and
irradiation
of the local environment.
b. DO NOT LOOK INTO THE OUTPUT PORT OF THE POWERED RF
AMPLIFIER. Treat the powered amplifier as though it is a loaded gun.
Your eyes are particularlyvulnerable parts
of your body.
c. SHUT OFF THE UNIT IF YOU ARE TRYING TO LOCATE AN RF
LEAK. As noted earlier, the levels of concern are very low. Examine
the physical
unit with the high voltage off. If you have to survey the RF
runs with the power on to find the leaky joint or component, start by
testing the system with low RF input with a radiation meter. If the
microwave radiation exceeds 0.5 mwjcm. sq. shut off the high power
voltage and consult your supervisor. Work quickly (not at apanic pace)
to minimize the dose level. The dose you get is directly proportional to
the
power level and the time you are exposed. Exposure to microwave
radiation can
induce both thermal and non-thermal biological effects,
especially
with the eyes. If you damage the lens of your eyes by
exposure to microwave radiation, cataracts can result. Consider that
small
microwave ovens are very effective in cooking foods. If you
follow these guidelines you can minimize exposure of yourself and
other people in the operations thatyou control.
CPI # 01023245 REV. 9
MAY 17,1999 S-9