BIRD Termaline 8930 Series User manual

Termaline® Load Resistor
Series 8930
Operation Manual

This unit requires the supplied vent plug be installed prior to use.
Operating the unit without the vent plug installed WILL result in equipment damage and may
cause personal injury.
© Copyright 2023 by Bird Technologies, Inc.
Instruction Book Part Number 920-8930S Rev. F
Termaline® is a Registered Trademark
of Bird Electronic Corporation

Safety Precautions
i
Safety Precautions
The following are general safety precautions that are not necessarily related to any specific part or procedure, and
do not necessarily appear elsewhere in this publication. These precautions must be thoroughly understood and
apply to all phases of operation and maintenance.

Keep Away From Live Circuits
Operating Personnel must at all times observe general safety precautions. Do not replace
components or make adjustments to the inside of the test equipment with the high voltage
supply turned on. To avoid casualties, always remove power.

Shock Hazard
Do not attempt to remove the RF transmission line while RF power is present.

Do Not Service Or Adjust Alone
Under no circumstances should any person reach into an enclosure for the purpose of service or
adjustment of equipment except in the presence of someone who is capable of rendering aid.

Safety Earth Ground
An uninterruptible earth safety ground must be supplied from the main power source to test
instruments. Grounding one conductor of a two conductor power cable is not sufficient
protection. Serious injury or death can occur if this grounding is not properly supplied.

Resuscitation
Personnel working with or near high voltages should be familiar with modern methods of
resuscitation.

Remove Power
Observe general safety precautions. Do not open the instrument with the power on.

Termaline® Load Resistor
ii
Safety Symbols

Warnings call attention to a procedure which, if not correctly performed, could result in
personal injury.

Cautions call attention to a procedure which, if not correctly performed, could result in damage
to the instrument.

Notes call attention to supplemental information.
This symbol indicates that a shock hazard exists if the precautions in the
instruction manual are not followed.
The caution symbol appears on the equipment indicating there is
important information in the instruction manual regarding that particular
area.
This symbol indicates that the unit radiates heat and should not be
touched while hot.

Safety Precautions
iii
Warning Statements
The following safety warnings appear in the text where there is danger to operating and maintenance personnel and
are repeated here for emphasis.

The load weighs 142 lb. (64.4 kg) lbs, do not attempt to lift alone. Two or more people are
required to lift the load. Injury may result from attempting to lift alone.
See page 3 and 5

The vent plug must be used at all times when the unit is in operation or cooling.
Always check to ensure vent plug is installed prior to operation.
Failure to do so WILL result in damage to the equipment and endanger the operator’s safety.
See pages 4, 5, and 17

Never attempt to connect or disconnect RF equipment from the transmission line while RF
power is being applied.
Leaking RF energy is a potential health hazard.
See pages 7, 9, 11, and 14

Turn off AC power and RF power when attaching the power cable.
See page 7

Do not touch the load during operation. During operation, load surfaces are extremely hot.
Touching the load during or after operation may cause burns.
See page 9

Disconnect the unit from all power sources before servicing.
The unit may be energized from multiple sources.
The potential for electric shock exists.
See pages 11, 13, 13, 16, 17, 18,and 19

Do not operate with side panel removed. Doing so could result in personal injury.
See page 13

Termaline® Load Resistor
iv
Caution Statements
The following equipment cautions appear in the text whenever the equipment is in danger of damage and are
repeated here for emphasis.

Do not block airflow. The air intake vent on the bottom of the load must not be obstructed.
See page 3

This load is designed for operation in a horizontal position only, with the mounting brackets
down.Operation in any other orientation will cause insufficient cooling of the unit leading to
premature failure.
See page 4

Blocking should be used to support the load to avoid damage to the RF connector. The RF
connector extends from the front of the load.
See page 5

Check the local electrical code for proper ac hookup prior to operation of the unit. Make sure
the neutral or return hookup is only used for that purpose.
See page 7

Maximum power is 2,500 W when the blower is not running. If the indicator light should turn
off, immediately reduce RF power to less than 2,500 W.
See page 9

If installed, connect optional interlock before applying RF power.
See page 9

Use only Bird coolant, P/N 5-1070, to prevent damage to the load.
See page 14

Safety Precautions
v
Safety Statements
USAGE
ANY USE OF THIS INSTRUMENT IN A MANNER NOT SPECIFIED BY THE MANUFACTURER MAY
IMPAIR THE INSTRUMENT’S SAFETY PROTECTION.
USO
EL USO DE ESTE INSTRUMENTO DE MANERA NO ESPECIFICADA POR EL FABRICANTE, PUEDE
ANULAR LA PROTECCIÓN DE SEGURIDAD DEL INSTRUMENTO.
BENUTZUNG
WIRD DAS GERÄT AUF ANDERE WEISE VERWENDET ALS VOM HERSTELLER BESCHRIEBEN,
KANN DIE GERÄTESICHERHEIT BEEINTRÄCHTIGT WERDEN.
UTILISATION
TOUTE UTILISATION DE CET INSTRUMENT QUI N’EST PAS EXPLICITEMENT PRÉVUE PAR LE
FABRICANT PEUT ENDOMMAGER LE DISPOSITIF DE PROTECTION DE L’INSTRUMENT.
IMPIEGO
QUALORA QUESTO STRUMENTO VENISSE UTILIZZATO IN MODO DIVERSO DA COME
SPECIFICATO DAL PRODUTTORE LA PROZIONE DI SICUREZZA POTREBBE VENIRNE
COMPROMESSA.

Termaline® Load Resistor
vi
SERVICE
SERVICING INSTRUCTIONS ARE FOR USE BY SERVICE - TRAINED PERSONNEL ONLY. TO AVOID
DANGEROUS ELECTRIC SHOCK, DO NOT PERFORM ANY SERVICING UNLESS QUALIFIED TO DO
SO.
SERVICIO
LAS INSTRUCCIONES DE SERVICIO SON PARA USO EXCLUSIVO DEL PERSONAL DE SERVICIO
CAPACITADO. PARA EVITAR EL PELIGRO DE DESCARGÉAS ELCTRICAS, NO REALICE NINGÚN
SERVICIO A MENOS QUE ESTÉ CAPACITADO PARA HACERIO.
WARTUNG
ANWEISUNGEN FÜR DIE WARTUNG DES GERÄTES GELTEN NUR FÜR GESCHULTES
FACHPERSONAL.
ZUR VERMEIDUNG GEFÄHRLICHE, ELEKTRISCHE SCHOCKS, SIND WARTUNGSARBEITEN
AUSSCHLIEßLICH VON QUALIFIZIERTEM SERVICEPERSONAL DURCHZUFÜHREN.
ENTRENTIEN
L’EMPLOI DES INSTRUCTIONS D’ENTRETIEN DOIT ÊTRE RÉSERVÉ AU PERSONNEL FORMÉ AUX
OPÉRATIONS D’ENTRETIEN. POUR PRÉVENIR UN CHOC ÉLECTRIQUE DANGEREUX, NE PAS
EFFECTUER D’ENTRETIEN SI L’ON N’A PAS ÉTÉ QUALIFIÉ POUR CE FAIRE.
ASSISTENZA TECNICA
LE ISTRUZIONI RELATIVE ALL’ASSISTENZA SONO PREVISTE ESCLUSIVAMENTE PER IL
PERSONALE OPPORTUNAMENTE ADDESTRATO. PER EVITARE PERICOLOSE SCOSSE
ELETTRICHE NON EFFETTUARRE ALCUNA RIPARAZIONE A MENO CHE QUALIFICATI A FARLA.

Safety Precautions
vii
CONNECT INTERLOCK TO TRANSMITTER/GENERATOR/AMPLIFIER BEFORE OPERATING.
BRANCHER LE VERROUILLAGE À L’ÉMETTEUR/GÉNÉRATEUR/AMPLIFICATEUR AVANT EMPLOI.
CONECTE EL INTERBLOQUEO AL TRANSMISOR/GENERADOR/AMPLIFICADOR ANTES DE LA
OPERACION.
VOR INBETRIEBNAHME VERRIEGELUNG AM SENDER/GENERATOR/VERSTÄRKER
ANSCHLIESSEN.
PRIMA DI METTERE IN FUNZIONE L’APPARECCHIO, COLLEGARE IL DISPOSITIVO DI BLOCCO AL
TRASMETTITORE/GENERATORE/AMPLIFICATORE.

Termaline® Load Resistor
viii
About This Manual
This manual covers the models listed below:
Changes to this Manual
We have made every effort to ensure this manual is accurate. If you discover any errors, or if you have suggestions
for improving this manual, please send your comments to our Solon, Ohio factory. This manual may be periodically
updated. When inquiring about updates to this manual refer to the part number and revision on the title page.
Chapter Layout
Introduction — Describes the features of the Bird Termaline RF Load Resistor lists equipment supplied and
optional equipment, and provides power-up instructions.
Theory of Operation — Describes how the Termaline RF Load Resistor works and its functions.
Installation — Describes the how to install the Termaline RF Load Resistor.
Operation with Blower — Describes procedures require for operating the load resistor equipped with a blower
unit.
Maintenance — Lists routine maintenance tasks as well as troubleshooting for common problems. Specifications
and parts information are also included.
Connector 115 VAC 230 VAC
Female LC 8931-115 8931-230
1-5/8" EIA Flanged 8932-115 8932-230
3-1/8" EIA Flanged 8936-115 8936-230
3-1/8" Unflanged, Flush Center 8937-115 8937-230
3-1/8" Unflanged, Recessed
Center
8938-115 8938-230

ix
Table of Contents
Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .i
Safety Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
Warning Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
Caution Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iv
Safety Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
About This Manual viii
Changes to this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .viii
Chapter Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .viii
Chapter 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Items Supplied . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Items Required but not Supplied . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Chapter 2 Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Load Resistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Power Rating Reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Thermal Interlock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Chapter 3 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Unpacking and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Site and Shelter Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Tools Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Vent Plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Thermoswitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Interlock Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
AC Power Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Connecting RF Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Swivel Flanged Coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Unflanged Coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Chapter 4 Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Blower Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Normal Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Operation Under Abnormal Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Emergency Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Chapter 5 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Routine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Inspect the Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Clean the Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Clean the Blower Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Inspect the Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
RF Assembly Resistance Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Termaline® Load Resistor
x
Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
RF Connector Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Load Resistor Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Indicator Light Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Fuse Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Fan Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Storage and Shipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Storing the Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Shipping the Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Customer Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Available “QC” Type Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Limited Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

1
Chapter 1 Introduction
Bird 8930 Series Loads are general purpose, 50 ohm, coaxial RF transmission line terminations, useful as standby
reject loads for single or double sideband transmitters. They provide accurate, dependable, and low reflection line
terminations over a frequency range of DC – 1000 MHz. Up to 10,000 watts can be dissipated.
The loads have a coolant chamber surrounded by radiator fins. The front and rear fins form mounting flanges which
can be used as supports for freestanding use or as brackets for fixed mounting. A vent plug at the top of the unit
relieves internal pressure from coolant expansion. A blower with three axial fans is on the bottom of the load. The
load’s simple and rugged design minimizes maintenance requirements.
Items Supplied

The load is pre-filled with coolant at the factory
Load Resistor
Detachable 3-wire power cable (without male plug for 230 VAC power cable)
One Shipping Plug
One Vent Plug
Instruction Manual
Items Required but not Supplied
Coupling Kit: Connects the load to the RF line
Male plug for the power cable (230 VAC only)
Optional Accessories
Interlock Thermoswitch: Automatically shuts off the transmitter to prevent overheating of the load
Figure 1 Bird 8930 Series Outline Drawing

2
Chapter 2 Theory of Operation
Load Resistor
Bird 8930 Loads consist of a thin-film-on-ceramic resistor immersed in a dielectric coolant. The resistor, individually
selected for its accuracy, is enclosed in a special housing. When surrounded by the coolant, this produces a uniform,
practically reflection-less line termination over the specified frequencies.
Coolant
The load is cooled by forced air and natural fluid convection currents. The coolant, chosen for its desirable dielectric
and thermal characteristics, carries heat from the resistor to the walls of the cooling tank, where radiator fins
surrounding the tank transfer the heat to the forced air flow.
When the coolant is heated, thermal expansion causes an increase in the internal pressure. A vent plug relieves this
pressure while protecting the opening from dirt or other contaminants.
Fans
Forced airflow is provided by three axial fans beneath the heat exchanger. Baffles direct the air over the radiator fins
for more efficient cooling. A passive, normally open control thermoswitch closes when the coolant reaches 60 °C
(140 °F), turning the fans on.
Power Rating Reduction
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Maximum power is 2,500 W when the blower is not running.
If the indicator light turns off, immediately reduce RF power to less than 2,500 W.
The baffles interfere with the free flow of normal air currents, causing a 75% reduction in heat transfer efficiency if
the forced airflow is stopped. The maximum power dissipation when the fans are not functioning is 2.5 kW.
Thermal Interlock
When installed, a passive, normally closed over-temperature thermoswitch opens above the maximum safe load
temperature of 226 °C (439 °F), turning off transmitter power. The interlock will not permit use of the transmitter
until the load has reached a safe temperature.

3
Chapter 3 Installation
Unpacking and Inspection
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The load weighs 142 lb. (64.4 kg) lbs, do not attempt to lift alone. Two or more people are
required to lift the load. Injury may result from attempting to lift alone.
1. Carefully inspect shipping container for signs of damage.
If the shipping container is damaged, do not unpack the unit. Immediately notify the shipping carrier and
Bird Technologies.
If the shipping container is not damaged, unpack the unit. Save shipping materials for repackaging.
2. Inspect unit for visual signs of damage.
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If there is damage, immediately notify the shipping carrier and Bird Technologies.
Site and Shelter Requirements
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Do not block airflow. The air intake vent on the bottom of the load must not be obstructed.
The unit should be operated in a dry, dust and vibration free environment.
Do not use outdoors or in areas of condensing humidity.
The ambient temperature range should remain between -40 to +45 °C (-40 to +113 °F)@ 60 Hz or – 40 to +40 °C (–
40 to +104 °F) @ 50 Hz for proper operation.
Allow at least 15" (40 cm) of clearance on all sides of the load, or mount it over a suitably reinforced opening
measuring 26"L x 7"W x 5"D (660 x 178 x 127 mm).
Place the unit as close as possible to the transmitting equipment, to permit the shortest possible cable length.
Tools Required
The following tools and supplies will be required to prepare the unit for use:
Wrenches
Screwdrivers
Bolt and nut sets or lag screws for mounting) (38“(9.53 mm) max. diameter)
These tools and supplies are required for the optional thermoswitch installation:
9/16 Hex wrench
Pipe sealing compound (Loctite 567)
Soldering Iron and solder
Torque Wrench

Termaline® Load Resistor
4
Mounting
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This load is designed for operation in a horizontal position only, with the mounting brackets
down.Operation in any other orientation will cause insufficient cooling of the unit leading to
premature failure.
Bird 8930 Loads are intended for stationary or fixed use. The mounting brackets on front and rear faces have four
mounting holes arranged in a 7" x 272332" (114.3 x 526.3 mm) rectangle. Use a screw with a 38" (9.5 mm) diameter
max.
The following instructions are for mounting the unit to a suitable surface.
1. Place the unit on a flat surface.
2. Insert the bolts through the surface and the mounting slots.
3. Secure the bolts with nuts and lock washers.
Vent Plug
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The vent plug must be installed at all times when the unit is in operation or cooling.
Always check to ensure vent plug is installed prior to operation.
Failure to do so WILL result in damage to the equipment and endanger the operator’s safety.
Before placing the unit into service, the solid shipping plug, P/N 2450-049, must be removed and replaced by the
spring loaded vent plug, P/N 2450-094. The plugs are linked together by a short length of bead chain.
1. Locate the vent hole for the plug, located at the top near the front.
See
Figure 1 on page 1 .
2. Remove the shipping plug.
3. Verify the O-Ring is installed on the vent plug.
4. Install the vent plug.

Installation
5
Thermoswitch
Bird 8930 Loads can be equipped with an optional interlock thermoswitch, P/N 8890-017. It is normally closed,
opening at 226 °C (439 °F), with a rating of 10A @ 120VAC and 5A @ 230VAC.
A control thermoswitch, P/N 8892-333, is used to control the blower assembly. It is normally open, closing at 60 °C
(140 °F), with a rating of 10A @ 120VAC and 5A @ 230VAC.
To install or replace a thermoswitch, follow these instructions:
1. Remove the vent plug.
2. Verify the O-Ring is installed on the shipping plug.
3. Install the shipping plug.
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The load weighs 142 lb. (64.4 kg) lbs, do not attempt to lift alone. Two or more people are
required to lift the load. Injury may result from attempting to lift alone.
4. Do one of the following:
For Interlock Thermoswitch:
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Blocking should be used to support the load to avoid damage to the RF connector.
The RF connector extends from the front of the load.
a. Supporting the load to prevent damage to the RF connector, stand the unit on its front with the RF
connector down. In this position there is no danger of coolant spillage.
b. Remove the socket plug on the back of the unit with a 916" hex wrench. See
Figure 1 on page 1 .
For Control Thermoswitch:
a. Remove the AC power cord from the back of the unit.
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Blocking should be used to support the load to avoid damage to the thermoswitch.
The thermoswitch extends from the back of the load.
b. Stand the unit on its back end, with the RF connector up. In this position there is no danger of coolant
spillage.
c. Remove the socket plug with a 916" hex wrench. See
Figure 1 on page 1 .
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Do not contaminate the coolant with pipe sealant.
5. Sparingly apply pipe sealing compound to only the external threads of the thermoswitch.
6. Install the thermoswitch in place of the plug. Torque to 40 +/-2 ft-lbs.
7. Lower the attenuator back onto its feet.
8. Check the unit for coolant leaks.
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The vent plug must be used at all times when the unit is in operation or cooling.
Always check to ensure vent plug is installed prior to operation.
Failure to do so WILL result in damage to the equipment and endanger the operator’s safety.

Termaline® Load Resistor
6
9. Remove the shipping plug.
10. Verify the O-Ring is installed on the vent plug.
11. Install the vent plug.
Interlock Connection
If installed, connect the optional interlock thermoswitch to the interlock as follows (see Figure 2 ):
If installed, connect optional interlock before applying RF power.
1. Unscrew the larger knurled ring-nut (A) at the lower end of the coupling jack assembly.
2. Pull the interlock connector off the thermoswitch jack (B).
3. Unscrew the small knurled cover fitting (C) from the base plug (D) of the connector to release the base.
4. Thread the interlock wires through the clamp (E) with the washers (F) inside and with its threaded fitting in
place.
5. Service the interlock/control switch wires with short tips and put spaghetti sleeves over the wire ends if
necessary.
6. Securely solder the wire leads to the lugs (G) of the connector base.
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The ring-nut (A) must be in place over the base plug (D) with the knurled end facing out.
7. Screw on the cover fitting (C).
8. Fasten the cable clamp (E) in place.
9. Tighten both yoke screws (H).
10. Push the plug back on the thermoswitch.
11. Tighten the nut (A).
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Do not attempt to operate the equipment without the interlock attached.
12. Connect the Thermoswitch wiring to the transmitter’s interlock.
Figure 2 Thermoswitch Connections

Installation
7
AC Power Connection
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Turn off AC power and RF power when attaching the power cable.
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Check the local electrical code for proper ac hookup prior to operation of the unit. Make sure
the neutral or return hookup is only used for that purpose.
The AC power supply required for this unit is 115/230 V, depending on the model, @ 50/60 Hz, 1. The blower is
equipped with an IEC 320 “cold” (65C) AC inlet.
Connecting RF Power
Before first using the load, perform the following steps.
1. Wipe all connectors and insulator surfaces on the transmission line face with a clean soft cloth.
2. Check the RF input connector for signs of wear, damage, or dirt.
3. Clean the connector if necessary. Use a self-drying, non-residue forming contact cleaner on the interior portions
of the connector.
4. Check the input resistance of the load. Refer to
"RF Assembly Resistance Test" on page 14 for details.
5. The RF transmission line can be attached using standard coaxial line coupling kits.

Never attempt to connect or disconnect RF equipment from the transmission line while RF
power is being applied.
Leaking RF energy is a potential health hazard.
“QC” Connector Coupling — Use 50 ohm coaxial cable such as RG-218/U or -220/U (-17A or -19A), appropriate
for the frequency and power level of operation. Use a cable connector which will mate with the one on the load.
Swivel Flanged Coupling
To couple the swivel flange with a flanged RF transmission line, use an appropriate coupling kit. Refer to Figure 3
while following the instructions below:
Figure 3 Swivel Flanged Coupling
Insert the center bullet and push it in until it is fully seated.
Connect the coaxial input in a straight line and push carefully on the center conductor to close.
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Termaline® Load Resistor
8

The swivel flange on the load makes connection independent of the orientation of the fixed
flange on the coaxial input outer conductor.
Insert the bolt sets and tighten evenly all around to transmission line manufacturer’s recommended
torque. Use all of the bolts.
Unflanged Coupling
To couple the unflanged connector with an unflanged RF line, use an appropriate coupling kit. Refer to Figure 4
while following the instructions below:
Figure 4 Unflanged Coupling
Insert the center bullet and bottom it on the midpoint nibs.
Position the outer sleeve, with clamping bands, over the input connector.
Set the transmission line snugly against the coupling stops.
Position the clamping bands evenly about 3/4” from the ends of the sleeve.
Tighten the clamping bands.
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