BIRD Termaline 8860SC Series User manual

Termaline® Semiconductor
Load Resistor
Series 8860SC
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 920-8860-SEMICON Rev. C
Termaline® and Tenuline® are Registered Trademarks
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® Semiconductor 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 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 this could result in damage to the equipment and endanger the operator’s safety.
On page 4, 5, 8, and 14.

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.
On page 7, 8, 9 and 11.

Do not touch the load during operation. During operation, load surfaces are extremely hot.
Touching the load during or after operation may cause burns.
On page 8

Termaline® Semiconductor Load Resistor
iv
Caution Statements
The following equipment cautions appear in the text and are repeated here for emphasis.

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.
On page 4.

Blocking should be used to support the load to avoid damage to the RF connector.
The RF connector could extend up to 4.5 inches from the body of the load (depending on
configuration).
On page 5 and 13.

If installed, connect optional interlock before applying RF power.
On page 8.

Use only Bird coolant, P/N 5-1070, to prevent damage to the load.
On page 11.

Blocking should be used to support the load to avoid damage to the interlock thermoswitch.
On page 13.

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® Semiconductor 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 DESCARGAS ELÉCTRICAS, 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 BEFORE OPERATING.
BRANCHER LE VERROUILLAGE À L'ÉMETTEUR AVANT EMPLOI.
CONECTE EL INTERBLOQUEO AL TRANSMISOR ANTES DE LA OPERACION.
VOR INBETRIEBNAHME VERRIEGELUNG AM SENDER ANSCHLIESSEN.
PRIMA DI METTERE IN FUNZIONE L'APPARECCHIO, COLLEGARE IL DISPOSITIVO DI BLOCCO AL
TRASMETTITORE.

Termaline® Semiconductor Load Resistor
viii
About This Manual
This manual covers the operating and maintenance instructions for the following models:
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, Semiconductor, RF Load Resistor, lists equipment
supplied and optional equipment, and provides power-up instructions.
Theory of Operation — Describes how to connect Semiconductor, RF Load Resistor to the user’s system,
describes the vector network analyzer measurements, and provides quick start steps for each measurement.
Installation — Describes the power measurement feature, lists compatible power sensors, describes how to
connect SignalHawk to the user’s system, and provides quick start steps to make power measurements.
Operating Instructions — Describes procedures required for operating the load resistor.
Maintenance — Lists routine maintenance tasks as well as troubleshooting for common problems. Specifications
and parts information are also included.
8865SC13

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
Thermal Interlock (Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Chapter 3 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Unpacking and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Site and Shelter Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Tools Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Mounting the Load Resistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Vent Plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Thermoswitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Thermoswitch Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Thermoswitch Wiring Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Connecting the RF Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Chapter 4 Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Normal Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Operation Under Abnormal Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Emergency Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Chapter 5 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Routine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Inspect the Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Clean the Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Inspect the Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
RF Assembly Resistance Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
DC Resistance Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Replace RF Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Repairing the Load Resistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Storage and Shipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Termaline® Semiconductor Load Resistor
x
Storing the Load Resistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Shipping the Load Resistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Customer Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Available “QC” Type Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Limited Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

1
Chapter 1 Introduction
Bird 8860 Series Semiconductor Loads are portable 50 ohm coaxial RF transmission line terminations. They are
designed for frequency ranges of DC – 28 MHz, specially calibrated for greater stability at 13.56 MHz. They provide
accurate, dependable, and low reflection line terminations. Up to 1000 watts of RF power can be dissipated.
The load has 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. The load’s simple and rugged design minimizes maintenance
requirements.
Items Supplied

Load Resistor is pre-filled with coolant at the factory
Load Resistor
Shipping Plug
Vent Plug
Instruction Manual
Items Required but not Supplied
Coupling Kit: Connects the load to the RF line.
Optional Accessories
Interlock Thermoswitch: Automatically shuts off the generator to prevent overheating of the load.
Figure 1 Bird 8860 Series Outline Drawing

2
Chapter 2 Theory of Operation
Load Resistor
Bird 8860 series 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 natural fluid and air convection currents. The coolant, chosen for its 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 air.
When the coolant is heated, thermal expansion causes an increase in the internal pressure. The vent plug relieves
this pressure while protecting the opening from dirt or other contaminants.
Thermal Interlock (Optional)
Loads can be supplied with an optional passive over-temperature thermoswitch. Normally closed, it opens at the
maximum safe load temperature of 236 °C (457 °F), turning off power to the RF generator. The interlock system will
not permit reoperation of the generator until the load has reached a lower, safe temperature.

3
Chapter 3 Installation
Unpacking and Inspection
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.

If there is damage, immediately notify the shipping carrier and Bird Technologies.
Site and Shelter Requirements
The unit should be operated in a dry, dust and vibration free environment.
The ambient temperature range should remain between +5 to +40 °C (+41 to +104 °F) for proper operation.
Allow at least 12" (305 mm) of clearance around the unit to permit an unimpeded access of convection air currents
for adequate heat dissipation.
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 optional thermoswitch installation:
9/16 Hex wrench
Pipe sealing compound (Loctite 567, or equivalent)
Soldering Iron and solder
Torque Wrench

Termaline® Semiconductor Load Resistor
4
Mounting the Load Resistor

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.
These loads are equipped for either portable use or fixed installation. The mounting brackets on the front and rear
faces have four mounting slots arranged in a 412" x 14732" rectangle (114.3 x 361.2 mm). Use a screw with a 38"
(9.53 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

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 attenuator 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 two plugs are linked together by a short length of bead chain.
1. Locate the vent hole for the plug, located at the top left hand side 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
As an option, the load may be provided with a thermoswitch assembly, P/N 8890-008. The thermoswitch is used as
an interlock switch to disable transmitter power if the coolant temperature exceeds a preset temperature, thus
preventing possible damage from accidental power overloading from the transmitter or equipment malfunction.
The thermoswitch is normally closed and opens at a maximum safe temperature. Since the thermoswitch is
connected in series with the transmitter interlock, it cuts off transmitter power if the coolant temperature exceeds
this value.
The assembly consists of:
Thermoswitch - P/N 8890-005
Connector - P/N 2450-018
Thermoswitch Installation
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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Blocking should be used to support the load to avoid damage to the RF connector.
The RF connector could extend up to 4.5 inches from the body of the load (depending on
configuration).
4. Stand the unit on its front, supporting it so that the connector is not damaged.
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In this position, there is no danger of the coolant pouring out through the socket plug hole.
5. Remove the socket plug from the location of the thermoswitch , using a 916" hex wrench. See
Figure 1 on
page 1
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Do not contaminate the coolant with pipe sealing compound.
6. Sparingly apply pipe sealing compound to the external threads, only,
7. Install the thermoswitch in place of the plug. Torque to 40 +/-2 ft-lbs.
8. Lower the unit back onto its feet.
9. Check 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.
10. Remove the shipping plug.
11. Verify the O-Ring is installed on the vent plug.
12. Install the vent plug.

Termaline® Semiconductor Load Resistor
6
Thermoswitch Wiring Installation
1. Unscrew the large knurled ring-nut (A) at the lower end of the coupling jack assembly.
2. Pull the large knurled ring-nut (A) off the thermoswitch jack (B). See
Figure 2 on page 6 .
3. Unscrew the small knurled cover fitting (C) from the base plug (D) of the connector to release the base.
4. Thread the control switch wires through the clamp (E) with the washers (F) inside and with its threaded fitting in
place.
5. Service the control switch wire with short tips and put spaghetti sleeves over the wire ends if necessary.
6. Securely solder the control switch 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 ring (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 knurled ring-nut (A).

Do not attempt to operate the equipment without the interlock attached.
12. Connect the Thermoswitch wiring to the transmitter’s interlock.
Figure 2 Thermoswitch Assembly

Installation
7
Connecting the 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 11 for details.
5. The RF transmission line can be attached using standard coaxial line coupling kits.

Never attempt to 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.

8
Chapter 4 Operating Instructions
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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 this could result in damage to the equipment and endanger the operator’s safety.

Do not touch the load during operation. During operation, load surfaces are extremely hot.
Touching the load during or after operation may cause burns.

If installed, connect optional interlock before applying RF power.
Normal Operation
Bird 8860 series loads have no indicators or operating controls. They require no special operating procedures or
surveillance when their performance limits are not exceeded. Follow the instructions for the specific generator
equipment.
Operation Under Abnormal Conditions
The load can be subjected to moderate overloads for short periods. If this is likely, make sure the interlock is
properly connected to prevent damage to the load.
Shutdown

Never attempt to disconnect RF equipment from the transmission line while RF power is being
applied. Leaking RF energy is a potential health hazard.
Turn off RF power at the source.
These loads are passive devices, so have no way of being turned off. Turn off RF power at the source.
Emergency Shutdown
Turn off RF power at the source.
If the interlock thermoswitch is properly connected, RF power will be automatically turned off when the coolant
temperature reaches an unsafe level.