Harris Gates One 994 9202 002 User manual

GATES ONE - 994 9202 002
GATES TWO - 994 9203 002
GATES FIVE (1-PHASE) - 994 9204 002
GATES FIVE (3-PHASE) - 994 9205 002
T.M. No. 888-2314-001 Printed: 1990
©Copyright 1990, 1991, 1992, 1994, 1995, 1996, 1998, 1999,
2000, 2001, 2002 Rev. AF: 06-21-02
Harris Corporation
All rights reserved
TECHNICAL MANUAL
GATES Series™
AM TRANSMITTERS

Returns And Exchanges
Damaged or undamaged equipment should not be returned unless written approval and a
Return Authorization is received from HARRIS CORPORATION, Broadcast Systems Divi-
sion. Special shipping instructions and coding will be provided to assure proper handling.
Complete details regarding circumstances and reasons for return are to be included in the
request for return. Custom equipment or special order equipment is not returnable. In those
instances where return or exchange of equipment is at the request of the customer, or
convenience of the customer, a restocking fee will be charged. All returns will be sent
freight prepaid and properly insured by the customer. When communicating with HARRIS
CORPORATION, Broadcast Systems Division, specify the HARRIS Order Number or In-
voice Number. Unpacking
Carefully unpack the equipment and preform a visual inspection to determine that no appar-
ent damage was incurred during shipment. Retain the shipping materials until it has been
determined that all received equipment is not damaged. Locate and retain all PACKING
CHECK LISTs. Use the PACKING CHECK LIST to help locate and identify any components
or assemblies which are removed for shipping and must be reinstalled. Also remove any
shipping supports, straps, and packing materials prior to initial turn on.
Technical Assistance
HARRIS Technical and Troubleshooting assistance is available from HARRIS Field Service
during normal business hours (8:00 AM - 5:00 PM Central Time). Emergency service is
available 24 hours a day. Telephone [phone] to contact the Field Service Department
or address correspondence to Field Service Department, HARRIS CORPORATION, Broad-
cast Systems Division, P.O. Box 4290, Quincy, Illinois 62305-4290, USA. Technical Support
by e-mail: [email protected]. The HARRIS factory may also be contacted through a FAX
facility (217/221-7096). Replaceable Parts Service
Replacement parts are available 24 hours a day, seven days a week from the HARRIS
Service Parts Department. Telephone [phone] to contact the service parts department
or address correspondence to Service Parts Department, HARRIS CORPORATION, Broad-
cast Systems Division, P.O. Box 4290, Quincy, Illinois 62305-4290, USA. The HARRIS fac-
tory may also be contacted through a FAX facility (217/221-7096).
NOTE
The # symbol used in the parts list means used with (e.g. #C001 = used with C001).

MANUAL REVISION HISTORY
GATES Series™ AM Transmitters
888-2314-xxx
Rev. Date ECN Pages Affected
A April 1990 None Replaced the following pages: Title Page, v, vii, 2-1 thru 2-6, 3-3, 3-4, 4-3, 4-4, 5-1 thru 5-6, J-3, & J-4
Added MRH-1/MRH-2
B Aug. 1990 None Replaced the following pages: Title Page, v, 3-5, 3-6, 4-1 thru 4-4, A-1, B-1, B-2, C-2, E-3, F-1 thru F-3,
G-1 thru G-4, J-1, J-2, J-3, J-4, J-9 thru J-11, & K-3
C Aug. 1990 35969 Replaced the following pages: Title Page, MRH-1/MRH-2, C-4, & C-5
D Aug. 1990 Field
Service
Request
Replace the following pages: Title Page, MRH-1/MRH-2, & 2-5
E Sept. 1990 36322 Replace the following pages: Title Page, MRH-1/MRH-2, & all of Section VI
F Oct. 1990 36415 Replace the following pages: Title Page, MRH-1/MRH-2, & all of Section A
G Jan. 1991 Errata
FS
Request
Replace the following pages: Title Page, MRH-1/MRH-2, & all of Section VI
H June 1991 FS
Request Replace the following pages: Title Page, MRH-1/MRH-2, 2-6, G-2, & J-3
I July 1991 36962 Replace the following pages: Title Page, MRH-1/MRH-2, and K-3
J Aug. 1991 36963 Replace the following pages: Title Page, MRH-1/MRH-2, 6-9 to 6-12, & J-9 TO J-11
K Jan. 1992 37611 &
Misc Replaced Title Page, MRH-1/MRH-2 and all part lists in manual
L June 1992 37442 Replaced Title Page, MRH-1/MRH-2 and pages 6-14 to 6-17
M Jan. 1994 38809 Replaced Title Page, MRH-1/MRH-2, page K-3, and all of section VI
N Feb. 1994 38895 Replaced Title Page, MRH-1/MRH-2, and pages F-4 & F-5
P July 1994 39302 Replaced Title Page, MRH-1/MRH-2, and all of section VI
R Dec. 1994 39223 Replaced Title Page, MRH-1/MRH-2, and pages F-4 & F-5
S July 1995 39125 Replaced Title Page, MRH-1/MRH-2, and all of section VI
T Jan. 1996 41051R Replaced Title Page, MRH-1/MRH-2, Table of Contents, 1-2 to 1-4, all of sections 2, 4, & 5
U Jan. 1996 41051R Replaced Title Page, MRH-1/MRH-2, and pages 6-15 to 6-19
V Mar. 1996 TBD Replaced Title Page, MRH-1/MRH-2, and page 2-9
X Dec. 1996 41575 Replaced Title Page, MRH-1/MRH-2, iv thru vi, and all of Section C
Y May 1998 42198 Replaced Title Page, MRH-1/MRH-2, and page 2-4
Y1 10-02-98 42359 Replaced Title Page, MRH-1/MRH-2, page G-6 and all of Section VI
Z 12-22-98 38895A Replaced Title Page, MRH-1/MRH-2, and all of Section F
Z1 2-15-99 42544 Replaced Title Page, MRH-1/MRH-2, and pages C-4 & C-5.
Z2 2-25-99 42636 Replaced Title Page, MRH-1/MRH-2, and all of Section VI
AA 08-18-99 45024 Replaced Title Page, MRH-1/MRH-2, and all of Section H
AB 12-10-99 45544 Replaced Title Page, MRH-1/MRH-2 and pages 2-4 and 2-5
AC 02-20-00 45748 Replaced Title Page, MRH-1/MRH-2 and all of Section II
AD 10-04-01 47730 Replaced Title Page, MRH-1/MRH-2 and page 3-6
AD1 01-15-02 47924 Replaced Title Page, MRH-1/MRH-2, and all of Section VI
AE 03-05-02 48100 Replace Title Page, MRH1/MRH2, all parts lists and chapter B.
AF 06-21-02 48426 Replace Title Page, MRH1/MRH2, and page C-3
888-2314-001 MRH-1/MRH-2

Guide to Using Harris Parts List Information
The Harris Replaceable Parts List Index portrays a tree structure with the major items being leftmost in the index. The
example below shows the Transmitter as the highest item in the tree structure. If you were to look at the bill of materials
table for the Transmitter you would find the Control Cabinet, the PA Cabinet, and the Output Cabinet. In the Replaceable
Parts List Index the Control Cabinet, PA Cabinet, and Output Cabinet show up one indentation level below the Transmitter
and implies that they are used in the Transmitter. The Controller Board is indented one level below the Control Cabinet so
it will show up in the bill of material for the Control Cabinet. The tree structure of this same index is shown to the right of
the table and shows indentation level versus tree structure level.
Example of Replaceable Parts List Index and equivalent tree structure:
The part number of the item is shown to the right of the description as is the page in the manual where the bill for that part
number starts.
Inside the actual tables, four main headings are used:
Table #-#. ITEM NAME - HARRIS PART NUMBER -this line gives the information that corresponds to the Replace-
able Parts List Index entry;
HARRIS P/N column gives the ten digit Harris part number (usually in ascending order);
DESCRIPTION column gives a 25 character or less description of the part number;
REF. SYMBOLS/EXPLANATIONS column 1) gives the reference designators for the item (i.e., C001, R102, etc.) that
corresponds to the number found in the schematics (C001 in a bill of material is equivalent to C1 on the schematic) or
2) gives added information or further explanation (i.e., “Used for 208V operation only,” or “Used for HT 10LS only,”
etc.).
Inside the individual tables some standard conventions are used:
A # symbol in front of a component such as #C001 under the REF. SYMBOLS/EXPLANATIONS column means that
this item is used on or with C001 and is not the actual part number for C001.
In the ten digit part numbers, if the last three numbers are 000, the item is a part that Harris has purchased and has not
manufactured or modified. If the last three numbers are other than 000, the item is either manufactured by Harris or is
purchased from a vendor and modified for use in the Harris product.
The first three digits of the ten digit part number tell which family the part number belongs to - for example, all
electrolytic (can) capacitors will be in the same family (524 xxxx 000). If an electrolytic (can) capacitor is found to
have a 9xx xxxx xxx part number (a number outside of the normal family of numbers), it has probably been modified
in some manner at the Harris factory and will therefore show up farther down into the individual parts list (because
each table is normally sorted in ascending order). Most Harris made or modified assemblies will have 9xx xxxx xxx
numbers associated with them.
The term “SEE HIGHER LEVEL BILL” in the description column implies that the reference designated part number
will show up in a bill that is higher in the tree structure. This is often the case for components that may be frequency
determinant or voltage determinant and are called out in a higher level bill structure that is more customer dependent
than the bill at a lower level.
Rev. X 888-2314-001 iii
WARNING: Disconnect primary power prior to servicing.

iv 888-2314-001 Rev. X
WARNING: Disconnect primary power prior to servicing.

WARNING
THE CURRENTS AND VOLTAGES IN THIS EQUIPMENT ARE DANGEROUS. PERSONNEL MUST
AT ALL TIMES OBSERVE SAFETY WARNINGS, INSTRUCTIONS AND REGULATIONS.
This manual is intended as a general guide for trained and qualified personnel who are aware of the dangers inherent in
handling potentially hazardous electrical/electronic circuits. It is not intended to contain a complete statement of all safety
precautions which should be observed by personnel in using this or other electronic equipment.
The installation, operation, maintenance and service of this equipment involves risks both to personnel and equipment, and
must be performed only by qualified personnel exercising due care. HARRIS CORPORATION shall not be responsible for
injury or damage resulting from improper procedures or from the use of improperly trained or inexperienced personnel
performing such tasks.
During installation and operation of this equipment, local building codes and fire protection standards must be observed.
The following National Fire Protection Association (NFPA) standards are recommended as reference:
- Automatic Fire Detectors, No. 72E
- Installation, Maintenance, and Use of Portable Fire Extinguishers, No. 10
- Halogenated Fire Extinguishing Agent Systems, No. 12A
WARNING
ALWAYS DISCONNECT POWER BEFORE OPENING COVERS, DOORS, ENCLOSURES, GATES,
PANELS OR SHIELDS. ALWAYS USE GROUNDING STICKS AND SHORT OUT HIGH VOLTAGE
POINTS BEFORE SERVICING. NEVER MAKE INTERNAL ADJUSTMENTS, PERFORM MAINTE-
NANCE OR SERVICE WHEN ALONE OR WHEN FATIGUED.
Do not remove, short-circuit or tamper with interlock switches on access covers, doors, enclosures, gates, panels or shields.
Keep away from live circuits, know your equipment and don’t take chances.
WARNING
IN CASE OF EMERGENCY ENSURE THAT POWER HAS BEEN DISCONNECTED.
WARNING
IF OIL FILLED OR ELECTROLYTIC CAPACITORS ARE UTILIZED IN YOUR EQUIPMENT, AND IF
A LEAK OR BULGE IS APPARENT ON THE CAPACITOR CASE WHEN THE UNIT IS OPENED FOR
SERVICE OR MAINTENANCE, ALLOW THE UNIT TO COOL DOWN BEFORE ATTEMPTING TO
REMOVE THE DEFECTIVE CAPACITOR. DO NOT ATTEMPT TO SERVICE A DEFECTIVE CAPACI-
TOR WHILE IT IS HOT DUE TO THE POSSIBILITY OF A CASE RUPTURE AND SUBSEQUENT
INJURY.
Rev. X 888-2314-001 v
WARNING: Disconnect primary power prior to servicing.

vi 888-2314-001 Rev. X
WARNING: Disconnect primary power prior to servicing.

FIRST-AID
Personnel engaged in the installation, operation, maintenance or servicing of this equipment are urged to become familiar
with first-aid theory and practices. The following information is not intended to be complete first-aid procedures, it is a
brief and is only to be used as a reference. It is the duty of all personnel using the equipment to be prepared to give
adequate Emergency First Aid and thereby prevent avoidable loss of life.
Treatment of Electrical Burns
1. Extensive burned and broken skin
a. Cover area with clean sheet or cloth. (Cleanest available cloth article.)
b. Do not break blisters, remove tissue, remove adhered particles of clothing, or apply any salve or ointment.
c. Treat victim for shock as required.
d. Arrange transportation to a hospital as quickly as possible.
e. If arms or legs are affected keep them elevated.
NOTE
If medical help will not be available within an hour and the victim is
conscious and not vomiting, give him a weak solution of salt and
soda: 1 level teaspoonful of salt and 1/2 level teaspoonful of baking
soda to each quart of water (neither hot or cold). Allow victim to sip
slowly about 4 ounces (a half of glass) over a period of 15 minutes.
Discontinue fluid if vomiting occurs. (Do not give alcohol.)
2. Less severe burns - (1st & 2nd degree)
a. Apply cool (not ice cold) compresses using the cleanest available cloth article.
b. Do not break blisters, remove tissue, remove adhered particles of clothing, or apply salve or ointment.
c. Apply clean dry dressing if necessary.
d. Treat victim for shock as required.
e. Arrange transportation to a hospital as quickly as possible.
f. If arms or legs are affected keep them elevated.
REFERENCE:
ILLINOIS HEART ASSOCIATION
AMERICAN RED CROSS STANDARD FIRST AID AND PERSONAL SAFETY MANUAL (SEC-
OND EDITION)
Rev. X 888-2314-001 vii
WARNING: Disconnect primary power prior to servicing.

TABLE OF CONTENTS
SECTION I
GENERAL INFORMATION
Introduction......................................1-1
ScopeAndPurpose..............................1-1
Specifications....................................1-1
SECTION II
INSTALLATION/OPERATION
Introduction......................................2-1
Unpacking.......................................2-1
ReturnsandExchanges.............................2-1
GeneralInstallationInformation .....................2-1
Power Distribution for Optimum Transmitter Perform-
ance .........................................2-1
OverheatingfromLineUnbalance..............2-1
TransmitterNoisePerformance ................2-1
TheCausesofLineUnbalance.................2-1
ThreePhaseDeltaDistributionTransformers.....2-2
ThreePhaseWyeDistributionTransformers......2-2
General Installation
Requirements ...................................2-2
EquipmentPlacement............................2-2
Pre-InstallationInspection ........................2-2
EquipmentPositioning...........................2-3
Ground Strap Installation .........................2-3
ElectricalInstallation ..............................2-3
PowerRequirements.............................2-3
Procedure. .................................2-3
RFOutputConnection...........................2-4
BatteryInstallation..............................2-4
Audio Input ....................................2-4
RemoteControl.................................2-4
AirflowSensorStatus............................2-5
FailsafeConnection..............................2-5
Modulation Monitor Sample ......................2-5
InitialTurnOnProcedure...........................2-5
InitialTurnOn .................................2-5
Modulation Monitor Carrier Level..................2-6
ApplicationofAudio ............................2-7
RemoteMeterCalibration ........................2-7
SECTION III
MAINTENANCE
Introduction......................................3-1
StationRecords...................................3-1
Maintenance Logbook ...........................3-1
PreventiveMaintenance............................3-1
Maintenance Of Components......................3-1
AirSystem.....................................3-2
GATES Series™ Top Removal
Procedure ....................................3-2
LowVoltageSupplyAdjustment...................3-2
High Voltage Supply Adjustment ..................3-4
RFDriveMeasurement...........................3-4
IPATuning....................................3-5
PAVoltageElectricalZero .......................3-5
PAVoltMeterCalibration........................3-5
PACurrentCalibration...........................3-5
Power Supply Current Calibration..................3-5
PowerOutputCalibration........................ 3-5
OverloadAdjustmentProcedures.................. 3-6
Power Supply Current Overload ............... 3-6
UnderdriveFault............................ 3-6
VSWRDetector............................ 3-6
Replacing Boards and
ReplacingBoardComponents ..................... 3-6
SECTION IV
TROUBLESHOOTING
Introduction..................................... 4-1
Definition of
FrontPanelIndicators ............................ 4-1
Symptom: Transmitter Will Not Turn On - None of
the Green LED’s on the Power Level Switches are Il-
luminated....................................... 4-1
PossibleCauses................................ 4-1
LossofACPower.......................... 4-1
ControlSupplyFailure....................... 4-1
Symptom: Green Power Level Status LED’s Illumi-
nate, but the Primary Contactors Do Not Energize and
NoOverloadLED’sIlluminate..................... 4-1
PossibleCauses................................ 4-1
Phase Monitor (3∅FIVEonly)................ 4-1
Blownfuse................................ 4-1
OpenInterlock............................. 4-1
FailsafeInterlockOpen...................... 4-1
InterfaceboardOutput....................... 4-1
OpenContactorCircuit...................... 4-1
ContactorControlSignal..................... 4-1
Symptom: One or Both Primary Contactors Energize,
ButThereIsNoPowerOutput..................... 4-1
HighVoltageSupplyFailure...................... 4-1
Symptom: High Voltage Is Present, But There Is No
PowerOutput................................... 4-2
PDMKillCondition ............................ 4-2
PDMLevel.................................... 4-2
PossibleCausesForOverloads...................... 4-2
Supply Voltage Overload ........................ 4-2
Supply Voltage Too High .................... 4-2
Power Supply Current Overloads- At Turn On ....... 4-2
Supply Short............................... 4-2
Power Supply Current Overloads, Continuous Cycling
andAutomaticCutback......................... 4-2
PDMSystemProblem....................... 4-2
PDMGeneratorOutputsHigh................. 4-2
PDMAmplifierShorts....................... 4-2
Supply Current Calibration ................... 4-2
Random Supply Current Overloads With Modulation. . 4-2
Sub-audibleSignals......................... 4-2
UnderdriveFault ............................... 4-2
Low/NoDrive.............................. 4-2
IPAandPATransistors...................... 4-2
VSWR Overload- Continuous VSWR Cycling ....... 4-2
BadLoadImpedance........................ 4-2
AntennaProblem........................... 4-3
OutputNetwork............................ 4-3
viii 888-2314-001 Rev. X
WARNING: Disconnect primary power prior to servicing.

VSWR Trips With High Levels Of Modulation and
HighPower................................... 4-3
ImproperTuningandLoading................. 4-3
Antenna .................................. 4-3
OutputNetwork............................ 4-3
Symptom:RemoteControlFunctionsDoNotWork .... 4-3
PossibleCauses................................ 4-3
Remote/LocalSwitch........................ 4-3
RemoteControlImproperlyWired............. 4-3
RemoteControlUnitNotFunctioning.......... 4-3
RibbonConnectorsLoose.................... 4-3
CausesforaPAVolts/PAAmpsRatioChange ........ 4-3
No+20VoltstoPDMAmplifier.................. 4-3
ImpedanceChange ............................. 4-3
PAFailure.................................... 4-3
Troubleshooting AM Noise......................... 4-4
50/60Hz...................................... 4-4
AudioLinesareNormallyBalanced ............... 4-4
100/120Hz.................................... 4-4
300/360Hz.................................... 4-4
60kHz....................................... 4-4
RFINoiseonAudio ............................ 4-4
SECTION V
TRANSMITTER OVERALL
Introduction..................................... 5-1
Personnel Protection .............................. 5-1
PrinciplesOfOperation............................ 5-1
FET’SintheGATESSeries™.................... 5-1
PDMTheoryInBrief........................... 5-1
PolyphaseTheory .............................. 5-1
Audio/PDMSignalFlow......................... 5-1
PDMLoop.................................... 5-3
RFPowerFlow................................ 5-3
Failsafe....................................... 5-3
ACPowerFlow................................ 5-3
High Voltage Power Supply ...................... 5-3
Introduction ............................... 5-3
Description................................ 5-3
Low Voltage Power Supply and IPA Power Supply. . . 5-6
Introduction ............................... 5-6
Description................................ 5-6
AirflowSensor................................. 5-6
Introduction ............................... 5-6
Description................................ 5-6
Section VI
Parts List
Introduction..................................... 6-1
SECTION A
OSCILLATOR (A16)
PrinciplesOfOperation............................ A-1
Replacement/Alignment ........................... A-1
FrequencyAdjustment........................... A-1
Troubleshooting the
RFOscillator ................................... A-1
Symptom:NoOutput ........................... A-1
OpenFuse/Lossof+20V..................... A-1
RFKILL.................................. A-1
Q1,Q2,CR1................................ A-1
U1,CR4...................................A-1
U2.......................................A-1
U3.......................................A-1
SECTION B
IPA (A5)
PrinciplesofOperation.............................B-1
IPATuningNetwork............................B-1
Replacement/Alignment............................B-1
IPA Tuning and Testing
Procedure......................................B-1
IPATuning................................B-1
OhmmeterTestingtheIPA .......................B-1
HandlingMOSFET’s..............................B-1
TestingMOSFET’s ...............................B-2
SECTION C
POWER AMPLIFIER A1 through A4
PrinciplesofOperation.............................C-1
PAToroids......................................C-1
Replacing a PA Module............................C-1
TroubleshootingthePABoards......................C-1
OhmmeterTesting..............................C-1
HandlingMOSFET’s..............................C-2
TestingMOSFET’s ...............................C-2
ReplacingPATransistors.........................C-2
ScopingtheRFDrive..............................C-2
RFDrivePhasingMeasurement.....................C-2
SECTION D
OUTPUT NETWORK
PrinciplesofOperation.............................D-1
AdjustmentProcedures.............................D-1
TuningAndLoadingControls.....................D-1
OutputNetworkColdTuning.....................D-1
ThirdHarmonicTrapL7-C4..................D-1
Bandpass Filter L2-C2 .......................D-1
TEENetwork-LoadandTune................D-1
L2SlidingTap .............................D-1
L1Tap....................................D-2
SECTION E
OUTPUT MONITOR (A18)
PrinciplesofOperation.............................E-1
Replacement/Alignment............................E-1
Troubleshooting..................................E-1
Symptom: Detector Null Reading Is High and Cannot
BeAdjustedToZero............................E-1
BadLoadImpedance........................E-1
SampleSignalMissing.......................E-1
SECTION F
PDM GENERATOR (A15)
PrinciplesOfOperation............................ F-1
Replacement/Alignment............................ F-1
TroubleshootingPDMGenerator..................... F-1
Symptom: No Pulses At J4, Causing Zero Power Out-
putfromtheTransmitter......................... F-1
PowerSetting.............................. F-1
LossofPlusandMinus15Volts............... F-1
PDMInterrupt.............................. F-1
DC/AudioFailure........................... F-1
Rev. X 888-2314-001 ix
WARNING: Disconnect primary power prior to servicing.

Symptom:ImbalanceInOutputPulseWidths ........F-2
AudioImbalance............................F-2
TriangleWaveImbalance.....................F-2
Symptom: Output(s) At J2 Always In A High State,
Causing One or More Pdm Amplifiers to Conduct
FullTime.....................................F-2
Symptom:OnlyOneOutputHigh..................F-3
Symptom:TwoOutputsAreHigh..................F-3
Symptom:AllFourOutputsAreHigh ..............F-3
SECTION G
PDM AMPLIFIER/PULL-UP (A6-A9)
PrinciplesofOperation............................ G-1
PDMAmplifier................................ G-1
PDMPull-UpBoard............................ G-1
Maintenance .................................... G-1
PDMAmplifiers............................... G-1
GateDriveChecks............................. G-1
In-Circuit Ohmmetering the PDM Amp Module (A6
thruA9)MOSFET’s........................... G-2
CheckingGateDrive........................ G-4
HandlingMOSFET’s............................. G-4
TestingMOSFET’s............................... G-4
SECTION H
PDM FILTER (A10 and A11)
PrinciplesofOperation............................ H-1
SECTION J
CONTROLLER BOARD (A12)
PrinciplesofOperation............................. J-1
CoarsePowerLevelControl ...................... J-1
ContactorControl............................... J-1
FinePowerControl.............................. J-1
Metering ...................................... J-1
OverloadCircuitry .............................. J-1
OtherFaultDetection............................ J-2
ControllerSupplyVoltages........................J-2
Replacement/AlignmentProcedures...................J-2
PAVoltageElectricalZero........................J-2
PAVoltMeterCalibration ........................J-2
Power Supply Current Calibration ..................J-2
PowerOutputCalibration.........................J-3
OverloadAdjustmentProcedures.....................J-3
Power Supply Current Overload ....................J-3
UnderdriveFault ................................J-3
VSWRDetector.................................J-3
Troubleshooting the Controller .......................J-3
Symptom: Will Not Respond To An On Command ....J-3
Controller Supply Failure......................J-3
Failedflipflopcircuitry.......................J-3
Symptom: PDM Power Level Signal Cannot Be Con-
trolled ........................................J-3
Symptom:MultimeterIsPinnedFarLeftorRight.....J-3
Symptom: Some Remote Control Functions Do Not
Work.........................................J-3
SECTION K
INTERFACE BOARD (A24)
PrinciplesofOperation............................ K-1
Replacement/Alignment............................ K-1
Troubleshooting ..................................K-1
Symptom: Green Power Level Status LED’s Light On
Controller,ButTheContactorsDoNotEnergize.....K-1
OpenInterlock.............................K-1
24VACMissing............................K-1
ONCommandMissing ...................... K-1
BadTriacorOpticalIsolator..................K-1
APPENDIX L
TEST EQUIPMENT
Introduction..................................... L-1
x 888-2314-001 Rev. X
WARNING: Disconnect primary power prior to servicing.

SECTION I
GENERAL INFORMATION
1.1. Introduction
1.1.1. Scope And Purpose
This technical manual contains the infor-
mation necessary to install and maintain the
GATES Series™AM Transmitters. The
various sections of this technical manual
provide the following types of information.
Section I, General Information, pro-
vides introduction to technical man-
ual contents.
Section II, Installation/operation, pro-
vides detailed installation and opera-
tion procedures.
Section III, Maintenance, provides
preventive and corrective mainte-
nance as well as tuning procedures
(alignment procedures).
Section IV, Troubleshooting, pro-
vides a listing of the protection de-
vices in the transmitter as well as
troubleshooting procedures.
Section V, Transmitter Overall, pro-
vides theory of operation of the vari-
ous sections of the transmitter not
covered in later sections.
Section VI, Parts List, provides parts
list for the transmitter.
The following sections provide principles
of operation, maintenance information,
troubleshooting,andpartslistsforboardsin
GATES Series™transmitter:
Section A, Oscillator
Section B, IPA
Section C, Power Amplifier
Section D, Output Network
Section E, Output Monitor
Section F, PDM Generator
Section G, PDM Amplifier/Pull-Up
Section H, PDM Filter
Section J, Controller
Section K, Interface Board
Appendix L, Test Equipment, pro-
vides a list of the test equipment pro-
vided and recommended to perform
maintenance on the transmitter.
1.2. Specifications
Table 1-1, 1-2, and 1-3 list the specifica-
tions of the GATES Series™transmitters.
NOTE
Specifications subject to change without
notice.
Rev. T: Jan. 1996 888-2314-001 1-1
WARNING: Disconnect primary power prior to servicing.

POWER OUTPUT: 1000 watts (Rated). Six power levels adjustable between 100-1100 watts. Capable
of lower power PSA/PSSA operation.
RF FREQUENCY RANGE: 531 kHz through 1705 kHz. Supplied to one frequency as ordered.
CARRIER FREQUENCY STABILITY: Crystal control oscillator meets FCC specifications. +/-4 Hz in typical operating
environment.
RF OUTPUT IMPEDANCE: 50 ohms unbalanced.
RF OUTPUT TUNING: Integral network will match a VSWR of 1.5:1 to 1.0:1 at carrier.
RF OUTPUT TERMINAL: Type N female connector.
CARRIER SHIFT: Less than 1% at 100% modulation at 1000 Hz.
RF HARMONICS AND SPURIOUS EMISSIONS: Exceeds FCC and CCIR specifications.
OTHER EMISSIONS: Meets FCC NRSC 2 when presented with audio signal conforming to NRSC 1
standard.
TYPE OF MODULATOR: Patented Polyphase PDM.
AUDIO FREQUENCY RESPONSE: +/-0.5 dB, from 20 to 10,000 Hz (with Bessel filter out).
AUDIO HARMONIC DISTORTION: Less than 1.0% at 1 kW, 20 to 10,000 Hz @ 95% modulation.
AUDIO INTERMODULATION DISTORTION: Less than 1.0%, 60/7000 Hz 1:1. Less than 1.5%, 60/7000 Hz 4:1, SMPTE
standards at 1 kW operation at 95% modulation.
SQUAREWAVE OVERSHOOT: Less than 3.5% at 400 Hz.
SQUAREWAVE TILT: Less than 3% at 20 Hz, 90% modulation.
Less than 1.5% at 40 Hz, 90% modulation.
NOISE (UNWEIGHTED) Better than 60 dB below 100% modulation, 1000 Hz at 1kW.
POSITIVE PEAK CAPABILITY: Greater than 130% positive peak program modulation capability at 1100 watts.
INCIDENTAL QUADRATURE MODULATION
(IQM): 30 dB typical below 95% modulation of L+R channel at 1 kHz.
AUDIO INPUT: Continuously adjustable from -10 to +10 dBm, transformer-less active 600 ohms
input.
AC VOLTAGE INPUT: 197-251 VAC, 50/60 Hz, single phase.
OVERALL EFFICIENCY: Better than 65% at 1000W.
POWER CONSUMPTION: At 1000 watts carrier, 1538 watts or less at 0% modulation, 2307 watts or less at
100% sine wave modulation, 1923 watts during typical programming.
MONITOR PROVISIONS: Adjustable to 5 volts nominal RMS modulated output sample at 50 ohms for six
power levels from 100 watts to 1100 watts.
REMOTE CONTROL/MONITORING: Self-contained interface for most remote control systems TTL compatible.
AMBIENT TEMPERATURE RANGE: -10°Cto+50°C AMSL (derate upper limit 2°C per 1000 feet altitude).
AMBIENT HUMIDITY RANGE: To 95%, non condensing.
AIR FLOW: 500 CFM
HEAT GENERATED: 2756 BTU per hour at 1 KW 100% tone modulation.
ALTITUDE: Up to 13,000 feet (4000 meters).
SIZE: 72"H X 28"W X 30"D (1830mm X 712 mm X 762 mm).
WEIGHT: (Unpacked) 400 lbs. (181 kg) - approximate. Domestic packed, 600 lbs. (275 kg)
- approximate. Export packed, 700 lbs. (320 kg) - approximate.
CUBAGE: 68.7 cubic feet (2 cubic meters) packed.
NOTE: ALL SPECIFICATIONS TAKEN WITH TRANSMITTER CONNECTED TO TEST LOAD. SPECIFICATIONS SUBJECT
TO CHANGE WITHOUT NOTICE.
Table 1-1. GATES ONE Specifications
1-2 888-2314-001 Rev. T: Jan. 1996
WARNING: Disconnect primary power prior to servicing.

POWER OUTPUT: 2500 watts (Rated). Six power levels adjustable between 250-2750 watts. Capable of
lower power PSA/PSSA operation.
RF FREQUENCY RANGE: 531 kHz through 1705 kHz. Supplied to one frequency as ordered.
CARRIER FREQUENCY STABILITY: Crystal control oscillator meets FCC specifications. +/-4 Hz in typical operating
environment.
RF OUTPUT IMPEDANCE: 50 ohms unbalanced.
RF OUTPUT TUNING: Integral network will match a VSWR of 1.5:1 to 1.0:1 at carrier.
RF OUTPUT TERMINAL: 7/8" EIA male/female flange connector.
CARRIER SHIFT: Less than 1% at 100% modulation at 1000 Hz.
RF HARMONICS AND SPURIOUS EMIS-
SIONS: Exceeds FCC and CCIR specifications.
OTHEREMISSIONS: MeetsFCCNRSC2whenpresentedwithaudiosignalconformingtoNRSC1standard.
TYPE OF MODULATOR: Patented Polyphase PDM.
AUDIO FREQUENCY RESPONSE: +/-0.5 dB, from 20 to 10,000 Hz (with Bessel filter out).
AUDIO HARMONIC DISTORTION: Less than 1.0% at 2500 watts, 20 to 10,000 Hz @ 95% modulation.
AUDIO INTERMODULATION DISTORTION: Less than 1.0%, 60/7000 Hz 1:1. Less than 1.5%, 60/7000 Hz 4:1, SMPTE standards
at 2500 watts operation at 95% modulation.
SQUAREWAVE OVERSHOOT: Less than 3.5% at 400 Hz.
SQUAREWAVE TILT: Less than 3% at 20 Hz, 90% modulation.
Less than 1.5% at 40 Hz, 90% modulation.
NOISE (UNWEIGHTED): Better than 60 dB below 100% modulation, 1000 Hz at 2500 watts.
POSITIVE PEAK CAPABILITY: Greater than 130% positive peak program modulation capability at 2750 watts.
INCIDENTAL QUADRATURE MODULA-
TION (IQM): 30 dB typical below 95% modulation of L+R channel at 1 kHz.
AUDIO INPUT: Continuouslyadjustable from-10 to +10 dBm, transformer-lessactive600 ohms input.
AC VOLTAGE INPUT: 197-251 VAC, 50/60 Hz, single phase.
OVERALL EFFICIENCY: Better than 65% at 2500W.
POWER CONSUMPTION: At 2500 watts carrier, 3846 watts or less at 0% modulation, 5769 watts or less at 100%
sine wave modulation, 4807 watts during typical programming.
MONITOR PROVISIONS: Adjustable to 5 volts nominal RMS modulatedoutput sample at 50 ohms forsix power
levels from 250 watts to 2750 watts.
REMOTE CONTROL/MONITORING: Self-contained interface for most remote control systems TTL compatible.
AMBIENT TEMPERATURE RANGE: -10°Cto+50°C AMSL (derate upper limit 2°C per 1000 feet altitude).
AMBIENT HUMIDITY RANGE: To 95%, non condensing.
AIR FLOW: 500 CFM
HEAT GENERATED: 6895 BTU per hour at 2500 watts, 100% tone modulation.
ALTITUDE: Up to 13,000 feet (4000 meters).
SIZE: 72"H X 28"W X 30"D (1830 mm X 712 mm X 762 mm).
WEIGHT: (Unpacked) 450 lbs. (204 kg) - approximate. Domestic packed, 650 lbs. (298 kg) -
approximate. Export packed, 750 lbs. (343 kg) - approximate.
CUBAGE: 68.7 cubic feet (2 cubic meters) packed.
NOTE: ALL SPECIFICATIONS TAKEN WITH TRANSMITTER CONNECTED TO TEST LOAD. SPECIFICATIONS SUBJECT
TO CHANGE WITHOUT NOTICE.
Table 1-2. GATES TWO Specifications
Rev. T: Jan. 1996 888-2314-001 1-3
WARNING: Disconnect primary power prior to servicing.

POWER OUTPUT: 5000 watts (Rated). Six power levels adjustable between 500-5600 watts. Capable of
lower power PSA/PSSA operation.
RF FREQUENCY RANGE: 531 kHz through 1705 kHz. Supplied to one frequency as ordered.
CARRIER FREQUENCY STABILITY: Crystal control oscillator meets FCC specifications. +/-4 Hz in typical operating
environment.
RF OUTPUT IMPEDANCE: 50 ohms unbalanced.
RF OUTPUT TUNING: Integral network will match a VSWR of 1.5:1 to 1.0:1 at carrier.
RF OUTPUT TERMINAL: 7/8" EIA male/female flange connector.
CARRIER SHIFT: Less than 1% at 100% modulation at 1000 Hz.
RF HARMONICS AND SPURIOUS EMIS-
SIONS: Exceeds FCC and CCIR specifications.
OTHER EMISSIONS: Meets FCC NRSC 2 when presented with audio signal conforming to NRSC 1
standard.
TYPE OF MODULATOR: Patented Polyphase PDM.
AUDIO FREQUENCY RESPONSE: +/-0.5 dB, from 20 to 10,000 Hz (with Bessel filter out).
AUDIO HARMONIC DISTORTION: Less than 0.8% at 5000 watts, typically less than 1.5% at 1 kW, 20 to 10,000 Hz @
95% modulation.
AUDIO INTERMODULATION DISTORTION: Less than 1.0%, 60/7000 Hz 1:1. Less than 1.5%, 60/7000 Hz 4:1, SMPTE standards
at 5000 watts operation at 95% modulation.
SQUAREWAVE OVERSHOOT: Less than 3.5% at 400 Hz.
SQUAREWAVE TILT: Less than 3% at 20 Hz, 90% modulation.
Less than 1.5% at 40 Hz, 90% modulation.
NOISE (UNWEIGHTED): Better than 60 dB below 100% modulation, 1000 Hz at 2500 watts to 5000 watts.
POSITIVE PEAK CAPABILITY: Greater than 130% positive peak program modulation capability at 5600 watts.
INCIDENTAL QUADRATURE MODULA-
TION (IQM): 30 dB typical below 95% modulation of L+R channel at 1 kHz.
AUDIO INPUT: Continuouslyadjustablefrom-10to+10dBm,transformer-lessactive600ohmsinput.
AC VOLTAGE INPUT: 197-251 VAC, 50/60 Hz, three phase or international 341 to 434 VAC. Compatible
with WYE or closed delta power sources. AC voltage variation: +5, -10% for full
performance. Single phase version accepts 197 to 251 VAC 50/60 Hz.
OVERALL EFFICIENCY: Better than 65% at 5000W.
POWER CONSUMPTION: At 5000 watts carrier, 7692 watts or less at 0% modulation, 11538 watts or less at
100% sine wave modulation, 9615 watts during typical programming.
MONITOR PROVISIONS: Adjustable to 5 volts nominalRMS modulated output sample at 50 ohms forsix power
levels from 500 watts to 5600 watts.
REMOTE CONTROL/MONITORING: Self-contained interface for most remote control systems TTL compatible.
AMBIENT TEMPERATURE RANGE: -10°Cto+50°C AMSL (derate upper limit 2°C per 1000 feet altitude).
AMBIENT HUMIDITY RANGE: To 95%, non condensing.
AIR FLOW: 500 CFM, (14.16 CMM).
HEAT GENERATED: 13790 BTU per hour at 5000 watts, 100% tone modulation.
ALTITUDE: Up to 13,000 feet (4000 meters).
SIZE: 72"H X 28"W X 30"D (1830 mm X 712 mm X 762 mm).
WEIGHT: (Unpacked) 500 lbs. (230 kg) - approximate. Domestic packed, 700 lbs. (320 kg) -
approximate. Export packed, 800 lbs. (370 kg) - approximate.
CUBAGE: 68.7 cubic feet (2 cubic meters) packed.
NOTE: ALL SPECIFICATIONS TAKEN WITH TRANSMITTER CONNECTED TO TEST LOAD. SPECIFICATIONS SUBJECT
TO CHANGE WITHOUT NOTICE.
Table 1-3. GATES FIVE Specifications
1-4 888-2314-001 Rev. T: Jan. 1996
WARNING: Disconnect primary power prior to servicing.

SECTION II
INSTALLATION/OPERATION
2.1. Introduction
This section of the technical manual pro-
vides detailed installation procedures and
setup instructions for the GATES Series™
AM transmitters.
Under normal conditions, the GATES Se-
ries™Transmitters are shipped completely
assembled and ready for installation. How-
ever,ifadverseshippingconditions areantici-
pated, certain components may be removed
for transport in which case these components
will be properly identified with appropriate
instructions for reinstalling the components
and making wiring connections.
2.2. Unpacking
Carefully unpack the transmitter and per-
form a visual inspection to determine that no
apparent damage was incurred during ship-
ment.Retaintheshippingmaterialsuntilithas
been determined that the unit is not damaged.
The contents of the shipment should be as
indicatedonthePackingCheckListwhich
accompanies each shipment. If the contents
are incomplete or if the unit is damaged elec-
tricallyormechanically,notifytheCARRIER
and HARRIS CORPORATION.
2.3. Returns and Exchanges
Damaged or undamaged equipment should
not be returned unless written approval and a
ReturnAuthorizationisreceivedfromHARRIS
CORPORATION, Broadcast Transmission Di-
vision.Specialshipping instructionsand coding
will be provided to assure proper handling.
Complete details regarding circumstances and
reasonsforreturnaretobeincludedinthe
requestfor return.Customequipmentor special
order equipment is not returnable. In those in-
stances where return or exchange of equipment
is at the request of the customer, or convenience
ofthecustomer,arestockingfeewillbecharged.
Allreturnswillbesentfreightprepaidandprop-
erly insured by the customer. When communi-
cating with HARRIS CORPORATION,
Broadcast Transmission Division, specify the
Factory Order Number or Invoice Number.
2.4. General Installation Information
The GATES Series™Transmitters have
been designed for rapid installation. In ad-
dition to the 28 inch width by 30 inchdepth
of the equipment, a minimum of 24 inches
should be allowed for maintenance access
from both the front and rear of the cabinet.
Signal and power wires can be connected
through several different entries or any de-
sired combination thereof.
The holes for cable entrance are 2 inches
in diameter, and are located at the front and
rear bottom of each side panel. These en-
triesprovideameanstoentertheequipment
with wires that are then routed into the base
of the equipment.
Input power wiresshould run to the termi-
nal board installed in the base of the trans-
mitter. Access to this terminal board is
gained by removing the cover plate over the
face of the contactor chassis. The screws
holding the chassis must then be removed
and the chassis pulled forward.
The normal air flow through the transmit-
ter is taken in through the back of the unit
(at the bottom of the cabinet). Maximum
temperature at the base of the transmitter
should not be more than 50°C. The air
moves from the base of the cabinet into the
side panels and into the main enclosure. Air
passes over the heat sink fins in the side
panels and exits through the holes in the top
ofthecabinet.This providesefficientchim-
ney action cooling of all the Power Ampli-
fier and Modulator transistors.
The air that enters the main enclosure
passes directly over the components dissi-
pating heat and exhausts through the output
coils and out the top of the transmitter. The
circuit cards and their heat sinks have been
designed to provide a chimney action to the
maximum extent practical.
NOTE
Note that the two blowers have separate
air intakes. One is filtered and the other
is not. The unfiltered side is dedicated to
the PA side wall. No filter is needed be-
cause most of the air passes through the
heat sink fins. A small amount of air is
channeled in the cabinet to flush the PA
Toroids. At approximately one year in-
tervals, the PA heat sink fins should be
inspected and cleaned. They may be re-
moved by removing the 10/32 mounting
screws.
2.4.1. Power Distribution for Optimum
Transmitter Performance
(This section is applicable to the three
phase GATES FIVE only, as well as other
three phase equipment.)
For many years HARRIS engineers have
recommended that the three phase power
distribution system should be either a
closed delta or WYE configuration to pro-
vide better radio and television transmitter
performance by helping prevent line unbal-
ance. Operation with substantial voltage
unbalance from line to line results inhigher
than normal signal-to-noise ratio in the
transmitter output signal, increased three
phase transformer heating, and hot three
phase motors.
2.4.1.1. Overheating from Line Unbalance
Evenadeviceassimpleasathreephase
motor should be operated from a power line
in which the voltage is balanced within 1%. It
takes only a 3.5% line unbalance to produce
a 25% increase above normal temperature. A
5%unbalance willcausedestructivetempera-
ture rises of 50% greater than normal!
Similar characteristics can be expected in
the windings of a three phase power trans-
former down inside the cabinet of your trans-
mitter. Transformers and motors can be
designedwithextrasafetyfeatureswherether-
mal rise is limited to acceptable levels; how-
ever, in this case, other transmitter parameters
cannot be made acceptable at a reasonable
cost.
2.4.1.2. Transmitter Noise Performance
The most difficult parameter to meet with
power line unbalance is transmitter noise
performance. Most large transmitters use
six-phase or twelve-phase high voltage
power supplies. The energy storage capaci-
tors are expensive to install and large stored
energies make destructive faults inevitable.
A good design will have sufficient energy
storage capacitors to meet the specified sig-
nal-to-noise but not much more. When the
equipment is then operated from an unbal-
anced line, the power supply ripple fre-
quency will be twice the line frequency
instead of six to twelve times. It becomes
obvious that it would take three times as
much energy storage to achieve the original
performance goal.
2.4.1.3. The Causes of Line Unbalance
How does a line unbalance occur? It is a
rare case in which a large commercial
powerproducerwouldgenerateunbalanced
voltage, so we must look elsewhere in the
system. When you have large single phase
power users on a power line this can cause
uneven distribution of the line currents in
the system. Uneven currents through bal-
anced impedances will result in line-to-line
voltage unbalance.
Another likely source of this problem can
come from unbalanced impedances in the
power distribution system. Unbalanced im-
pedance will always be seen when an
“open”delta three phase distribution sys-
tem is used. Transformer design textbooks
Rev. AC: 2/29/00 888-2314-001 2-1
WARNING: Disconnect primary power prior to servicing.

clearly show that the voltage regulation of
an unbalanced system is poor.
2.4.1.4. Three Phase Delta Distribution
Transformers
Figure 2-1 shows open and closed delta
systems. The closed delta impedance look-
ing into each terminal (A, B & C) is exactly
thesame;butthisisnotthecaseintheopen
delta configuration. Depending on the im-
pedances of the transformers in the open
delta circuit, line voltage unbalance suffi-
cient to impair satisfactory operation of the
overall transmitter may result. For this rea-
son, along with theirinherent susceptibility
to transients, Harris does not recommend
the use of open delta systems.
The only advantage of the open delta is
lower initial cost, and this is partially offset
by the fact that when only two transformers
are used, they must be larger than the three
transformers in a closed delta system.
Difficulties have often been experienced
with open delta systems; but when a third
transformerwasaddedtoclosethedelta,the
problems disappeared.
There is another problem which can occur
with an open delta system, and that is
caused by lightning and switching tran-
sients. When lightning strikes or heavy
loads are switched on a power distribution
system, high voltage transients are propa-
gated throughout the system. Unbalanced
impedances will enhance these transients
and can cause transmitter damage, particu-
larly to solid state rectifiers.
Many transmitters are located at the end
of a long transmission line which is highly
susceptible to transient phenomena. De-
vices such as Metal Oxide Varistors are
inexpensive and very effective in reducing
over voltage spikes. These units are limited
in the amount of energy that can be dissi-
pated, but will handle, ifdesigned properly,
very large currents. You can’t take a direct
lightning hit and still operate, but not many
things will. It has been reported by engi-
neers that installation of a third transformer
and transient protection devices, have
eliminated the difficulty.
2.4.1.5. Three Phase Wye Distribution
Transformers
The WYE connected system is also con-
sidered a symmetrical form of three phase
power distribution. All impedances are bal-
anced as seen from each terminal (see Fig-
ure 2-2). It is important when using a WYE
connected system that the fourth wire (neu-
tral) is connected to the mid-point of the
system as shown in the diagram. When this
connectionismadeitprovidesapathforthe
zerosequencecurrentsaswellasanyhar-
monic currents which are generated due to
the rectification of the secondary voltages.
Today, many transformers are supplied
with all of the primary terminals available
sothateitheradeltaorWYEconnectioncan
be made. Table 2-1 shows the different line-
to-line voltages that are available with this
configuration.
In summary, both symmetrical power dis-
tribution systems are satisfactory because
of their balanced impedances. Use either a
closed delta or a four wire WYE system for
maximum transmitter performance. Never
use an open delta system just to cut costs -
it could cost dearly in the long run.
2.5. General Installation
Requirements
The key to a rapid and successful setup is
careful planning prior to delivery of the
system. HARRIS offers, as an option, engi-
neering services to review and comment on
proposedinstallations.InadditionHARRIS
offers, as an option, design, fabrication, and
installation services to any required level
for total integration of the system into a
facility.
2.5.1. Equipment Placement
The transmitter should be located to per-
mit adequate maintenance access and suffi-
cient ventilation. Primary AC power cables
can enter the transmitter at a variety of
locations and the specific location of entry
will need to be determined on site. The
grounding strap between the transmitter
and the station earth ground must be prop-
erly connected before AC power wiring is
attached to transmitter.
2.5.2. Pre-Installation Inspection
Prior to performing the installation of the
GATES Series™transmitter, it should be
thoroughly inspected for any connections
which may have loosened during shipment.
Figure 2-1. Three Phase Delta
Distribution Transformers Figure 2-2. Three Phase WYE
Distribution Transformers
Delta connected
transformer WYE connected transformer
210 364
220* 380*
230 400
240* 415*
250 433
* Typical voltages in some areas of the
world.
Table 2-1. Typical Line Voltages
Delta or WYE
Lifting Equipment
(Fork Lift, etc) 900 lbs (408 kg) capacity
Hand Tools For opening wooden
crates
Shims (2" by 2") Aluminum,assorted
thicknesses
Hand Operated
Hole Punch For adding 0.25" hardware holes to
0.020" thick copper
ground strap at
transmitter ground
connection.
Table 2-2. Special Installation
Tools and Equipment
Transformer, Low
Level, A20T01 472 1678 000 (1)
Transformer,
Power, A19T01 See packing list for part number
Table 2-3. Equipment Supplied with
Transmitter and Listed on Packing
Check List Supplied with Transmitter
2-2 888-2314-001 Rev. AC: 2/29/00
WARNING: Disconnect primary power prior to servicing.

This is important due to numerous high
current connections in the transmitter.
Also check that all ribbon cables are prop-
erly locked into their respective printed cir-
cuit board connectors.
The mechanical interconnecting integrity
of the above mentioned items is essential to
the attaining of proper transmitter opera-
tion. Although appropriate packaging and
shipping precautions are taken prior to the
equipment leaving the factory, hardware
may, in isolated cases, work loose in transit
and result in a failure.
Check for debris or loose hardware, espe-
cially around the high current power supply
connections.
2.5.3. Equipment Positioning
Following removal of the shipping mate-
rial, move the cabinet on its skid as near as
possible to its permanent position. If ship-
ping bolts have been used, they will be
locatedateachcorneroftheskid.Remove
the bolts from the underside of the skid.
NOTE
Positioning of the cabinet is to be per-
formed by experienced personnel to pre-
vent damage to the equipment or injury
to personnel.
With a suitable lifting device, raise one
end of the transmitter cabinet sufficiently to
permit the placing of three lengths of circu-
lar bar stock under the cabinet. In this man-
ner the cabinet can be efficiently and
carefully rolled off the skid.
2.5.4. Ground Strap Installation
The importance of a good grounding sys-
tem and lightning protection can hardly be
overemphasized for reasons of personnel
safety, protection of the equipment, and
equipment performance. The following is
only a brief overview.
Lightning and transient energy via the
powerlineortowerconnectionscanimpose
serious threats to your personal safety as
well as damage the equipment. For these
reasons you should have a good protective
earthing system to divert these forms of
energytoearthground.Propergroundingof
the equipmentalso guardsagainst electrical
shock hazards that would exist if the equip-
ment failed in a way which put a hazardous
voltage on the chassis.
A good grounding system should include
substantial grounding at the tower base us-
ing copper groundrods and/or a buried cop-
per ground screen, with copper strap used
to connect the tower base to earth ground.
A low impedance will help carry lightning
current directly into the ground instead of
into your building. Additionally, coax
shield(s)shouldbeelectricallyconnectedto
and exit the tower as near to the bottom as
practical to minimize the lightning voltage
potential carried by the coax into your
building.
For coaxes, a single point of entry into the
building is best, with all connected to a
common grounding plate (or bulkhead
panel) having a low impedance connection
tothebuildingperimeterground.Widecop-
per straps should be used for making the
connection from the common grounding
plate to earth ground.
Acommongroundingplateisalsothebest
locationforcoaxialsurgeprotectorsforsen-
sitive equipment such as an STL receiver.
Ideally, this plate should also be the entry
point for all signal lines, and serve as a
single point ground for AC power surge
protection.
A good ground system should include pe-
rimeter grounding of the transmitter build-
ing using copper ground rods and copper
strap. There should also be a copper strap
running from tower ground to the building
perimeter ground.
Good grounding and shielding will help
keep stray RF current to a minimum. RF
interference usually shows up in one of
several ways, intermittent problems with
digital or remote control circuits, audio
feedback or high pitched noise. Even a
smallamountofnon-shieldedwiremakesa
very efficient antenna for RF and transient
energy. If RF is allowed into the audio
equipment,itcanberectifiedandmay show
up as noise or feedback. Wire and cable
shields should normally be connected at
both ends to the equipment chassis.
Agroundstrapattachmentpointislocated
on the bottom, right rear, of the cabinet
behind the dust cover (uses a 10-32 brass
screw with brass washer). Use this connec-
tionwhen utilizinga singlepointgrounding
system, attaching your ground strap to the
common grounding plate. See 839-7920-
044 Gates series Outline drawing.
A grounding stud is also provided near the
AC input connections in the lower portion
of the transmitter. Use this connection for
the power line ground. It is located under
the low voltage power supply board.
2.6. Electrical Installation
NOTE
All GATES Series™ transmitters are
shipped with A19T1 and A20T1 con-
nected for 251 VAC operation. It is ad-
vised that the end user determine the ap-
propriate tap settings during the initial
turn-on. In this procedure, the trans-
former tapping is determined by the re-
sulting DC supply voltage. This ensures
that the DC supplies are operated in the
desired range.
2.6.1. Power Requirements
The GATES Series™GATES FIVE (3
phase version) is designed to operate from
a3phase,208/240VAC,50to60Hzsource.
Sixty ampere service is required. Use 6
gauge wire for this connection.
The single phase GATES FIVE requires a
100 amp 208/240 VAC, 50 to60 Hz source.
Use 4 gauge wire for this connection.
The GATES TWO requires a 60 amp
208/240 VAC, 50 to 60 Hz source. Use 6
gauge wire for this connection.
The GATES ONE requires a 30 amp
208/240 VAC, 50 to 60 Hz source. Use 8
gauge wire for this connection.
There is no requirement for 120 VAC in
any case.
As an option, the low voltage circuits can
be powered from a separate circuit breaker.
Although not a requirement, this set up some-
times is advantageous for maintenance and
troubleshooting. If you choose to wire your
transmitter this way, you will need to provide
a separate 10 amp circuit breaker.
NOTE
If service voltage is less than 208 VAC,
a higher current service may be needed.
Refer to the Outline drawing for mechani-
cal dimensions and wire feed locations.
WARNING
ENSURE THAT ALL AC POWER IS OFF
PRIOR TO STARTING THE FOLLOWING
INSTALLATION
2.6.1.1. Procedure.
For a three phase GATES FIVE, connect 3
phaseACinputpowerfromafuseddisconnect
box or circuit breaker to transmitter cabinet
terminal board TB1 terminals 1, 2 and 3. The
powersource can be either a closed delta (usu-
ally 230 to 240 volts) or a WYE (usually 208).
For a four wire WYE system (341 to 434
volts), connect the neutral wire to terminal
board TB1 terminal 4. Also for a WYE
system ensure that the high voltage trans-
former has been tapped correctly for the
configuration (see the Wiring Diagram for
the three phase GATES FIVE transmitter).
For the GATES ONE, GATES TWO, or
single phaseGATES FIVE, connect ACinput
power (197 to 251 VAC)from a fused discon-
nect box or circuit breaker to transmitter cabi-
net terminal board TB1 terminals 1 and 2.
NOTE
Terminal board TB1 is accessed by remov-
ing the four screws which hold the circuit
breaker panel to the front of the transmit-
Rev. AC: 2/29/00 888-2314-001 2-3
WARNING: Disconnect primary power prior to servicing.

ter and then sliding the circuit breaker
panel forward. Terminal board TB1 is
located on the floor of the transmitter di-
rectly below the AC Power panel. Termi-
nals are numbered left to right.
Ifyouchoosetowireyourtransmitterwith
separatelowvoltageandhighvoltagefeeds,
you will need to remove the factory in-
stalledjumperwiresfromTB1,andconnect
a10ampservicetoTB1terminals5and6.
For the 3 phase GATES FIVE, ensure that
the Phase Monitor relay A19K3 is installed
in the AC Power panel and is adjusted to
MIN.SeeNotebelow.
NOTE
To adjust the Phase Monitor, remove all
power from transmitter and rotate the voltage
adjustment screw to your approximate AC
line voltage. The actual setting will have to be
determined by trial and error. Refer to para-
graph 2.7.1.g for adjustment information.
2.6.2. RF Output Connection
Connect the output transmission line from
theantennatotheRFOUTPUTconnectorjack
J1 located on top of the transmitter cabinet.
A GATES ONE requires a male type N
connector. Specific type N connectors are
available for various types of coax.
TheGATESTWOandGATESFIVErequire
a 7/8 EIA flange. Specific connectors of this
type are available for various kinds of coax.
2.6.3. Battery Installation
The purpose of the battery on the Controller
board (on the swing out panel) is to maintain
transmitter operational status during a power
interruption. It is not important to install it until
you are nearly ready to put the transmitter
into regular operation. The transmitter will
operate properly without the battery, how-
ever, power interruptions lasting more than
a few seconds will result in an OFF condi-
tion, and all overload lights lit.
A standard 9 volt battery will last about 2
weeks of continuous running with no AC
powerapplied.Alkalinebatterieswillgivethe
longest shelf life. It is a good idea to change
the battery after a long outage or yearly.
2.6.4. Audio Input
Route the audio cable up from the base of
the transmitter to the Interface board. The
Interface board is located in the lower left
portion of the transmitter in the front. Con-
necttheaudioinputwiresto terminalsTB2-
26 and TB2-27 on the Interface Board.
TB2-28 is ground for the audio cable. Refer
to Table 2-4 and Figure 2-3.
2.6.5. Remote Control
Allremotecontrolconnectionsaremadeatthe
Interfaceboard.Cablingforremotecontrolmay
be routed up from the base of the transmitter.
CONTROL
INPUTS TERMINAL
Low TB2-1
Two TB2-2
Three TB2-3
Four TB2-4
Five TB2-5
High TB2-6
Off TB2-7
Raise TB2-8
Lower TB2-9
Ext Kill (RF mute) TB2-10
FAILSAFE TB1-1 and TB1-2
METERING
OUTPUTS TERMINAL
PA Voltage TB2-11
PS Current TB2-12
Power Output TB2-13
STATUS TERMINAL
Low TB2-15
Two TB2-16
Three TB2-17
Four TB2-18
Five TB2-19
High TB2-20
OVERLOAD
STATUS TERMINAL
Overload Ind Reset TB2-14
Auto Cutback TB2-21
Supply Voltage TB2-22
Supply Current TB2-23
Underdrive TB2-24
VSWR TB2-25
Audio TB2-26
Audio TB2-27
Ground TB2-28
Table 2-4. Interface Board Connections
Figure 2-3. Making Connections to WAGO Block
To prepare wire, strip insulation back approximately 1/4" and twist strands back into
their natural position.
A small flat blade screwdriver is an appropriate tool to use to make the connection.
To make connection, align wire in side opening “B”and depress clamp down from
opening “A”with tool. Insert wire or component in opening “B”andsecurebywithdraw-
ing tool.
2-4 888-2314-001 Rev. AC: 2/29/00
WARNING: Disconnect primary power prior to servicing.