Broadcast Electronics FX-50 User manual

Broadcast Electronics
4100 North 24th Street, Quincy, Illinois 62305 USA • Phone [phone] • Fax [phone] • www.bdcast.com • [e-mail]
FX-50, FX-50E
50 WATT
FM Exciter
Instruction Manual
597-1050
Rev B
December 15, 2011

FX-50, FX-50E. 50 WATT FM Exciter
Instruction Manual
©2011 Broadcast Electronics. All rights reserved.
The information in this publication is subject to improvement and change without notice. Although
every effort is made to ensure the accuracy of the information in this manual, Broadcast Electronics
accepts no responsibility for any errors or omissions. Broadcast Electronics reserves the right to
modify and improve the design and specifications of the equipment in this manual without notice.
Any modifications shall not adversely affect performance of the equipment so modified.
Proprietary Notice
This document contains proprietary data of Broadcast Electronics Inc. No part of this publication may
be reproduced, transmitted, transcribed, stored in a retrieval system, translated into any other
language in any form or by any means, electronic or mechanical, including photocopying or
recording, for any purpose, without the express written permission of Broadcast Electronics.
Trademarks
Broadcast Electronics and the BE logo are registered trademarks of Broadcast Electronics.
All other trademarks are property of their respective owners.

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Broadcast Electronics
Product Warranty (Two-Year Limited)
BE hereby warrants all new products manufactured by BE against any defects in material or
workmanship at the time of delivery thereof, or that develop under normal use within a period of
two (2) years from the date of shipment.
BE reserves the right to repair equipment under warranty with new or refurbished equipment or
parts. BE’s sole responsibility with respect to any equipment or parts not conforming to this
warranty is to replace or repair such equipment upon the return thereof F.O.B. to BE’s factory in
Quincy, Illinois, U.S.A. In the event of replacement pursuant to the foregoing warranty, only the
unexpired portion of the warranty from the time of the original purchase will remain in effect for
any such replacement.
This warranty shall exclude the following products, component parts and/or assemblies:
(a) Transmitter power output tubes shall only carry the original manufacturers’ or suppliers’
standard warranty in effect on their original shipment date.
(b) All computers, computer peripherals, cables, hard disk drives, etc., shall only carry the
manufacturers’ or suppliers’ standard warranty in effect on their original shipment date.
(c) “Components”, defined as separate and individual parts (e.g. transistors, integrated
circuits, capacitors, resistors, inductors, fans, etc), resold by BE from another manufacturer
or supplier, shall only carry a 90 day warranty, effective the date of shipment. Any such
‘Components’ being returned for warranty claim must be (1) returned in their original
packaging and (2) must be in new, unused condition.
BE is unable to process or resolve component defects or performance concerns on
components that have been soldered, installed, wired or in any way altered from new their
new condition.
(d) “Resale Equipment”, defined as equipment purchased from another manufacturer or
supplier, then resold by BE, shall only carry such manufacturers’ or suppliers’ standard
warranty in effect as of the original shipment date. All warranty claims against any and all
‘resale equipment’ sold by BE must be filed directly with the original equipment
manufacturer. BE is unable to process or resolve equipment defects or performance
concerns on products or services not manufactured by BE.
This warranty shall not extend to claims resulting from any acts of God, terrorism, war, defects or
failures caused by Purchaser or user abuse or misuse, operator error, or unauthorized attempts to
repair or alter the equipment in any way.
Under no circumstances shall BE be responsible for indirect, incidental or consequential damages,
including, but not limited to transportation costs, non-authorized repair or service costs, downtime
costs, costs for substituting equipment or loss of anticipated profits or revenue incurred by
Purchaser, whether based in contract, tort or for negligence or breach of statutory duty or
otherwise.
The terms of the foregoing warranty shall be null and void if the equipment has been altered or
repaired without specific written authorization from BE, or if not installed according to BE’s
instruction manuals including, but not limited to, the absence of proper grounding, surge (TVSS)
protection on the AC circuit panel or proper lightning protection/grounding on all output circuits,
or if equipment is operated under environmental conditions or circumstances other than those
specifically described in BE’s product literature or instruction manual which accompany the
equipment. The warranty shall be voided if the product or subassembly is equipped with a tamper
seal and that tamper seal is broken. BE shall not be liable for any expense of any nature
whatsoever incurred by the original user without prior written consent of BE.

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The warranty provided herein shall terminate at the end of the period set forth above. This
warranty extends only to the original Purchaser and is not transferable. There are no third party
beneficiaries of any of the provisions of this warranty. If the equipment is described as “used”
equipment, it is sold as is and where is and no warranty applies unless authorized in writing.
EXCEPT AS SET FORTH HEREIN, AS TO TITLE AND AS SPECIFICALLY REQUIRED BY LAW, THERE ARE
NO OTHER WARRANTIES, OR ANY AFFIRMATIONS OF FACT OR PROMISES BY BE, WITH REFERENCE
TO THE EQUIPMENT, OR TO MERCHANTABILITY, FITNESS FOR A PARTICULAR APPLICATION,
SIGNAL COVERAGE, INFRINGEMENT, OR OTHERWISE, WHICH EXTEND BEYOND THE DESCRIPTION
OF THE EQUIPMENT ON THE FACE HEREOF.

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IMPORTANT INFORMATION
EQUIPMENT LOST OR DAMAGED IN TRANSIT -
When delivering the equipment to you, the truck driver or carriers’ agent will present a receipt for
your signature. Do not sign it until you have:
1) Inspected the containers for visible signs of damage and 2) Counted the containers and
compared with the amount shown on the shipping papers. If a shortage or evidence of damage is
noted, insist that notation to that effect be made on the shipping papers before you sign them.
Further, after receiving the equipment, unpack it and inspect thoroughly for concealed damage. If
concealed damage is discovered, immediately notify the carrier, confirming the notification in
writing, and secure an inspection report. This item should be unpacked and inspected for damage
WITHIN 15 DAYS after receipt. Claims for loss or damage will not be honored without proper
notification of inspection by the carrier.
RF PRODUCT TECHNICAL ASSISTANCE, REPAIR SERVICE, PARTS -
Technical assistance is available from Broadcast Electronics by letter, prepaid telephone or E-mail.
Equipment requiring repair or overhaul should be sent by common carrier, prepaid, insured, and
well protected. If proper shipping materials are not available, contact the RF Technical Services
Department for a shipping container. Do not mail the equipment. We can assume no liability for
inbound damage, and necessary repairs become the obligation of the shipper. Prior arrangement
is necessary. Contact the RF Technical Services Department for a Return Authorization.
Emergency and warranty replacement parts may be ordered from the following address. Be sure
to include the equipment model number, serial number, part description, and part number. Non-
emergency replacement parts may be ordered directly from the Broadcast Electronics stock room
at the number shown below.
RF TECHNICAL SERVICES -
Telephone: [phone]
E-Mail: [email protected]
Fax: [phone]
FACILITY CONTACTS -
Broadcast Electronics, Quincy Facility
4100 N. 24th St. P.O. BOX 3606
Quincy, Illinois 62305
Telephone: [phone]
Fax: [phone]
General E-Mail: [email protected]
Web Site: www.bdcast.com
PARTS -
Telephone: [phone]
E-Mail: [e-mail]

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RETURN, REPAIR, AND EXCHANGES -
Do not return any merchandise without our written approval and Return Authorization. We will
provide special shipping instructions and a code number that will assure proper handling and
prompt issuance of credit. Please furnish complete details as to circumstances and reasons when
requesting return of merchandise. All returned merchandise must be sent freight prepaid and
properly insured by the customer.
MODIFICATIONS -
Broadcast Electronics, reserves the right to modify the design and specifications of the equipment
in this manual without notice. Any modifications shall not adversely affect performance of the
equipment so modified.

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SAFETY PRECAUTIONS
PLEASE READ AND OBSERVE ALL SAFETY PRECAUTIONS//
ALL PERSONS WHO WORK WITH OR ARE EXPOSED TO POWER TUBES, POWER
TRANSISTORS, OR EQUIPMENT WHICH UTILIZES SUCH DEVICES MUST TAKE
PRECAUTIONS TO PROTECT THEMSELVES AGAINST POSSIBLE SERIOUS BODILY INJURY.
EXERCISE EXTREME CARE AROUND SUCH PRODUCTS. UNINFORMED OR CARELESS
OPERATION OF THESE DEVICES CAN RESULT IN POOR PERFORMANCE, DAMAGE TO THE
DEVICE OR PROPERTY, SERIOUS BODILY INJURY, AND POSSIBLY DEATH.
DANGEROUS HAZARDS EXIST IN THE OPERATION OF POWER TUBES AND
POWER TRANSISTORS -
The operation of power tubes and power transistors involves one or more of the following
hazards, any one of which, in the absence of safe operating practices and precautions, could
result in serious harm to personnel.
A. HIGH VOLTAGE Normal operating voltages can be deadly. Additional information
follows.
B. RF RADIATION Exposure to RF radiation may cause serious bodily injury possibly
resulting in Blindness or death. Cardiac pacemakers may be affected. Additional
information follows.
C. HOT SURFACES Surfaces of air-cooled radiators and other parts of tubes can reach
temperatures of several hundred degrees centigrade and cause serious burns if
touched. Additional information follows.
D. RF BURNS Circuit boards with RF power transistors contain high RF potentials. Do not
operate an RF power module with the cover removed.

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HIGH VOLTAGE –
Many power circuits operate at voltages high enough to kill through electrocution. Personnel
should always break the primary AC Power when accessing the inside of the transmitter.
RADIO FREQUENCY RADIATION
Exposure of personnel to RF radiation should be minimized, personnel should not be permitted in
the vicinity of open energized RF generating circuits, or RF transmission systems (waveguides,
cables, connectors, etc.), or energized antennas. It is generally accepted that exposure to “high
levels” of radiation can result in severe bodily injury including blindness. Cardiac pacemakers may
be affected.
The effect of prolonged exposure to “low level” RF radiation continues to be a subject of
investigation and controversy. It is generally agreed that prolonged exposure of personnel to RF
radiation should be limited to an absolute minimum. It is also generally agreed that exposure
should be reduced in working areas where personnel heat load is above normal. A 10 mW/cm2
per one tenth hour average level has been adopted by several U.S. Government agencies
including the Occupational Safety and Health Administration (OSHA) as the standard protection
guide for employee work environments. An even stricter standard is recommended by the
American National Standards Institute which recommends a 1.0 mW/cm2 per one tenth hour
average level exposure between 30 Hz and 300 MHz as the standard employee protection guide
(ANSI C95.1-1982).
RF energy must be contained properly by shielding and transmission lines. All input and output RF
connections, such as cables, flanges and gaskets must be RF leak proof. Never operate a power
tube without a properly matched RF energy absorbing load attached. Never look into or expose
any part of the body to an antenna or open RF generating tube or circuit or RF transmission
system while energized. Monitor the tube and RF system for RF radiation leakage at regular
intervals and after servicing.
HOT SURFACES –
The power components in the transmitter are cooled by forced-air and natural convection. When
handling any components of the transmitter after it has been in operation, caution must always
be taken to ensure that the component is cool enough to handle without injury.

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Table of Contents
1OVERVIEW......................................................................................................................................1
1.1 RELATED PUBLICATIONS................................................................................................................... 1
1.2 EQUIPMENT DESCRIPTION................................................................................................................ 1
1.3 FX-50 AND FX-50E MODELS. ........................................................................................................... 2
1.4 PHYSICAL DESCRIPTION.................................................................................................................... 2
1.5 ELECTRICAL DESCRIPTION. ............................................................................................................... 2
1.6 EQUIPMENT SPECIFICATIONS. .......................................................................................................... 3
2INSTALLATION ................................................................................................................................7
2.1 UNPACKING. .................................................................................................................................... 7
2.2 INSTALLATION.................................................................................................................................. 7
2.3 WIRING. ......................................................................................................................................... 12
2.4 EXCITER CHECKOUT. ...................................................................................................................... 14
3OPERATION. .................................................................................................................................17
3.1 CONTROLS AND INDICATORS......................................................................................................... 17
3.2 OPERATION.................................................................................................................................... 17
4THEORY OF OPERATION................................................................................................................21
4.1 FUNCTIONAL DESCRIPTION. ........................................................................................................... 21
5MAINTENANCE.............................................................................................................................25
5.1 SAFETY CONSIDERATIONS.............................................................................................................. 25
5.2 FIRST LEVEL MAINTENANCE. .......................................................................................................... 25
5.3 SECOND LEVEL MAINTENANCE. ..................................................................................................... 25
5.4 TROUBLESHOOTING....................................................................................................................... 26
6POWER SUPPLY/CONTROL CIRCUIT ...............................................................................................31
6.1 DESCRIPTION.................................................................................................................................. 31
6.2 ELECTRICAL CHARACTERISTICS. ...................................................................................................... 31
6.3 REMOVAL AND INSTALLATION....................................................................................................... 32
6.4 THEORY OF OPERATION ................................................................................................................. 32
6.5 MAINTENANCE .............................................................................................................................. 38

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7EXCITER METERING CIRCUIT BOARD ............................................................................................45
7.1 DESCRIPTION.................................................................................................................................. 45
7.2 INTERNAL VOLTMETER CHARACTERISTICS...................................................................................... 45
7.3 REMOVAL AND INSTALLATION....................................................................................................... 45
7.4 THEORY OF OPERATION ................................................................................................................. 47
7.5 MAINTENANCE .............................................................................................................................. 50
8MODULATED OSCILLATOR............................................................................................................54
8.1 DESCRIPTION.................................................................................................................................. 54
8.2 ELECTRICAL CHARACTERISTICS. ...................................................................................................... 54
8.3 REMOVAL AND INSTALLATION....................................................................................................... 54
8.4 THEORY OF OPERATION ................................................................................................................. 55
8.5 FUNCTIONAL DESCRIPTION. ........................................................................................................... 55
8.6 MAINTENANCE .............................................................................................................................. 57
8.7 TROUBLESHOOTING....................................................................................................................... 57
9AFC/PLL……..................................................................................................................................58
9.1 DESCRIPTION.................................................................................................................................. 58
9.2 ELECTRICAL CHARACTERISTICS. ...................................................................................................... 58
9.3 REMOVAL AND INSTALLATION....................................................................................................... 59
9.4 THEORY OF OPERATION ................................................................................................................. 59
9.5 FUNCTIONAL DESCRIPTION. ........................................................................................................... 59
9.6 MAINTENANCE .............................................................................................................................. 64
9.7 ELECTRICAL ADJUSTMENTS. ........................................................................................................... 64
9.8 TROUBLESHOOTING....................................................................................................................... 70
10 RF AMPLIFIER ...............................................................................................................................74
10.1 DESCRIPTION.................................................................................................................................. 74
10.2 ELECTRICAL SPECIFICATIONS. ......................................................................................................... 74
10.3 REMOVAL AND INSTALLATION....................................................................................................... 74
10.4 THEORY OF OPERATION ................................................................................................................. 75
10.5 MAINTENANCE .............................................................................................................................. 78
10.6 TROUBLESHOOTING....................................................................................................................... 82
11 SYNCHRONOUS FM BOOSTER.......................................................................................................84
11.1 SYSTEM DESCRIPTION. ................................................................................................................... 84
11.2 SYSTEM CONFIGURATIONS. ........................................................................................................... 84
11.3 ELECTRICAL SPECIFICATIONS. ......................................................................................................... 84

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11.4 INSTALLATION................................................................................................................................ 85
11.5 INSTALLATION ADJUSTMENTS........................................................................................................ 86
11.6 THEORY OF OPERATION ................................................................................................................. 86
11.7 MAINTENANCE .............................................................................................................................. 90
12 BE Part Numbers..........................................................................................................................94
13 RF Technical Services Contact Information................................................................................148
14 Drawings…. ...............................................................................................................................148

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©2011 Broadcast Electronics
1OVERVIEW
Information presented by this section provides a general description of the FX-50/E FM Exciter features and lists
equipment specifications.
1.1 RELATED PUBLICATIONS.
The following list of publications provides data for equipment and options associated with the FX-50/E FM
Exciters.
PUBLICATION NUMBER EQUIPMENT
597-0008-004 FC-30 SCA Generator
597-9900 LYNX FM Digital Stereo Generator
1.2 EQUIPMENT DESCRIPTION.
The FX-50/E exciters are available in several configurations. Refer to the following list for various exciter models,
spare parts kits, and options available.
MODEL PART NO. DESCRIPTION
FX-50 909-1051-225 3-50 Watt FM exciter, 120V ac, 50/60 Hz, solid-state with
automatic power control and synthesized frequency control,
rack mount.
FX-50 909-1051-325 3-50 Watt FM exciter, 220V/240V ac, 50/60 Hz, solid-state
with automatic power control and synthesized frequency
control, rack mount.
FX-50E 909-1050-329 3-50 Watt FM exciter, 240V ac, 50 Hz, CE compliant.
Solid-state with automatic power control and synthesized
frequency control, rack mount.
---- 909-0124 Optional Low-Pass Filter.
---- 909-0131 Optional Master Synchronous FM Booster Circuit Board.
---- 909-0132 Optional Slave Synchronous FM Booster Circuit Board.
---- 979-1053 100% Spare Semiconductor Kit.
---- 979-1052 Recommended Spare Semiconductor Kit.
---- 979-1051 Spare Parts Kit.
---- 979-0152 Remote Exciter Kit.
---- 959-0315 Optional FM Notch Filter.

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1.3 FX-50 AND FX-50E MODELS.
The FX-50 and the FX-50E FM exciters are nearly identical in construction and features (refer to Figure 1-1).
However, the FX-50E meets stringent CE standards for locations requiring CE certification. Both units contain
identical control, metering, and RF amplifier circuitry. The units both exhibit excellent performance
specifications. However, FX-50E models are equipped with: 1) additional input/output and ac line filtering, 2) a
25-pin D- type remote interface connector, and 3) only a single rear-panel composite audio input receptacle
(unbalanced).
1.4 PHYSICAL DESCRIPTION.
The FX-50/E chassis is equipped with slide rails to allow easy access to all assemblies when the unit is extended
from the rack. Removal and installation of assemblies within the exciter is facilitated by the semimodular
mechanical construction. Each assembly is firmly mounted to the main chassis and electrically connected to the
main wiring harness with plugs and jacks. Front-panel test receptacles allow measurements of the composite
signal without removing the top-cover. On FX-50 units, input and output connections are routed to a rear-
panel terminal strip and several BNC connectors. On FX-50E units, input and output connections are routed to a
rear-panel 25-pin D-Type connector and several BNC connectors.
Figure 1-1. FX-50/E Exciter
1.5 ELECTRICAL DESCRIPTION.
The Broadcast Electronics FX-50/E exciters are solid-state wideband FM units providing a continuously variable
RF output from 3 to 50 watts into a 50 Ohm load at any frequency within the 87 to 109 MHz FM broadcast
band in 10 kHz increments. The FX-50/E accepts multiple wideband composite inputs from a stereo generator
or SCA generator in addition to a 600 Ohm balanced monaural input. Typical performance exhibits extremely
low distortion with THD and IMD less than 0.003% and a typical signal-to-noise ratio of 94 dB. A tapped dual
primary power transformer and a voltage selector allows operation from a wide range of ac input potentials.
1.5.1 METERING.
Exciter operating parameters are monitored by a front-panel digital LCD multimeter and an LED display.
Multimeter functions are identified by large LED indicators which illuminate when a function switch is operated.
The multimeter can also be operated as a high-impedance test meter for internal measurements. In addition, a
color coded moving bar LED display is incorporated to indicate peak modulation percentage in increments of
5%.

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1.5.2 STATUS DISPLAYS.
The FX-50/E exciters are designed with front-panel LEDs to indicate the status of three main exciter operating
potentials, three preset limits, and operating frequency stabilization. Additional LEDs are incorporated on the
AFC/PLL circuit board assembly to indicate the status of operating potentials and monitor reference oscillator
and modulated oscillator circuit conditions.
1.5.3 AUTOMATIC FREQUENCY CONTROL.
A temperature compensated reference oscillator and a dual-speed phase-locked-loop controlling the carrier
frequency locks the frequency of the modulated oscillator to the precision reference frequency oscillator
allowing prompt on-frequency operation of the exciter from a cold start. The FX-50/E will achieve frequency
lock from a cold start in less than five seconds.
1.5.4 CONTROL CIRCUIT.
The control circuitry provides automatic control of RF output to maintain a preset power output. In addition,
the control circuitry eliminates adjustments after the initial setup, protects the RF output circuitry from excessive
temperatures, high VSWR conditions, over-voltage conditions, and short circuit conditions.
RF AMPLIFIER.
The RF amplifier is a broadbanded 3 to 50 watt amplifier covering the entire commercial FM broadcast band.
Tuning of the amplifier is not required. An optional low-pass filter can be installed in the exciter to convert the
exciter to a low power transmitter for connection to an antenna.
1.6 EQUIPMENT SPECIFICATIONS.
Refer to Table 1-1 for electrical specifications and Table 1-2 for physical and environmental specifications of the
FX-50/E FM Exciters.
Table 1-1. FX-50/E Exciter Specifications
PARAMETER
SPECIFICATIONS
AC INPUT POWER REQUIREMENTS
FX-50
FX-50E
97 to 133V AC or 194 to 266V AC, 50/60 Hz, 230W Maximum
240V AC Nominal, 50/60 Hz, 230W Maximum.
RF OUTPUT IMPEDANCE 50 Ohms.
POWER OUTPUT 3 Watts to 50 Watts, Continuously Variable (BNC Connector)
Open and Short Circuit Protected.
R.F. HARMONIC AND SPURIOUS
SUPPRESSION (CONDUCTED)
Meets or exceeds all FCC, DOC, and CCIR standards.
FREQUENCY RANGE 87 MHz to 109 MHz Digitally Programmable in 10 kHz
increments.
FREQUENCY STABILITY +300 Hz, +32˚F to +122˚F (0˚C to +50˚C).
MODULATION TYPE Direct FM at the Carrier Frequency.
MODULATION CAPABILITY +350 kHz.

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MODULATION INDICATION Peak Reading, Color Coded, LED Display with Baseband Over-
Modulation Indicator.
ASYNCHRONOUS AM SIGNAL-TO-
NOISE RATIO
80 dB Below Equivalent Reference Carrier with 100% Amplitude
Modulation @ 400 Hz and 75 Microsecond Deemphasis (No FM
Modulation Present).
SYNCHRONOUS AM SIGNAL-TO-
NOISE RATIO
60 dB Below Equivalent Reference Carrier with 100% Amplitude
Modulation @ 1 kHz (FM Modulation: +75 kHz @ 400 Hz).
MULTIMETER 5 Function LCD Plus Diagnostic Aid, +3% Accurate.
TEST METERING Internal High Input Impedance Multimeter with Probe for
Internal DC Measurements.
FRONT PANEL TEST
CONNECTIONS
Composite Input and Composite Output.
AUDIO/CONTROL CONNECTIONS
FX-50
FX-50E
16 Terminal Barrier Strip and 5 BNC Connectors.
25-Pin D-Type Connector and 4 BNC Connectors.
WIDEBAND COMPOSITE
OPERATION
COMPOSITE INPUTS
FX-50 3 Total, Unbalanced (1) and Balanced (1) Plus Front Panel Test
Provision (1) (BNC Connectors).
FX-50E 2 Total, Unbalanced (1) and Front Panel Test Provision (1) (BNC
Connectors)
COMPOSITE INPUT IMPEDANCE
UNBALANCED 10 k Ohm, Nominal, Resistive.
BALANCED 10 k Ohm or 50 Ohm, Programmable Jumper Selected.
COMPOSITE INPUT LEVEL 3.5V p-p Nominal, for +75 kHz Deviation.
COMPOSITE FM SIGNAL-TO-NOISE
RATIO
90 dB Below +75 kHz Deviation @ 400 Hz (93 dB Typical).
Measured within a 20 Hz to 200 kHz Bandwidth with 75
Microsecond Deemphasis.
94 dB (96 dB Typical) with A weighting.
COMPOSITE HARMONIC
DISTORTION PLUS NOISE
0.005% or Less (0.003% Typical) at 400 Hz.
COMPOSITE SMPTE INTER-
MODULATION DISTORTION
0.005% or Less (0.003% Typical),
60 Hz/7 kHz 1:1 ratio.
COMPOSITE TRANSIENT IMD 0.01% or Less (Square Wave/Sine Wave.)
COMPOSITE AMPLITUDE +0.025 dB, 30 Hz to 53 kHz.

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RESPONSE
COMPOSITE PHASE RESPONSE +0.1˚ from Linear Phase 30 Hz to 53 kHz.
COMPOSITE GROUP DELAY
VARIATION
+5 Nanoseconds, 30 Hz to 100 kHz.
STEREOPHONIC SEPARATION 52 dB, 30 Hz to 15 kHz and 60 dB, 30 Hz to 5 kHz (Measured
using BE FS-30 Stereo Generator).
SCA INPUTS 3 Total, Unbalanced BNC Connectors.
SCA INPUT IMPEDANCE 100 k Ohm, Nominal, Resistive.
COMPOSITE CCIF INTER-
MODULATION DISTORTION
0.005% or Less, 15 kHz/14 kHz, 1:1 ratio.
SCA INPUT LEVEL 3.5V p-p Nominal for +7.5 kHz Deviation.
SCA AMPLITUDE RESPONSE +0.2 dB, 40 kHz to 100 kHz.
MONAURAL OPERATION
AUDIO INPUT IMPEDANCE 600 Ohms Balanced, Resistive, Adaptable to Other Impedances,
60 dB Common Mode Suppression.
AUDIO INPUT LEVEL +10 dBm Nominal for +75 kHz Deviation @ 400 Hz, Adaptable
to Other Levels.
AUDIO FREQUENCY RESPONSE +0.5 dB, 30 Hz to 15 kHz, Selectable Flat, 25, 50 or 75
Microsecond Preemphasis.
HARMONIC DISTORTION PLUS
NOISE
0.005% or Less at 400 Hz.
SMPTE INTERMODULATION
DISTORTION
0.005% or Less, 60 Hz to 7 kHz, 4:1 Ratio.
CCIF INTERMODULATION
DISTORTION
0.005% or Less, 15 kHz/14 kHz 1:1 Ratio.
TRANSIENT INTERMODULATION
DISTORTION
0.01% or Less (Square Wave/Sine Wave).
FM SIGNAL-TO-NOISE RATIO 90 dB Below +75 kHz Deviation @ 400 Hz (93 dB Typical)
Measured in a 20 Hz to 15 kHz Bandwidth with 75 Microsecond
Deemphasis.
94 dB (96 dB Typical) with A weighting.
REGULATORY
FX-50E ONLY Meets CE Specifications.

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SAFETY
FX-50/FX-50E Meets IEC 215 Specifications.
Table 1-2. PHYSICAL AND ENVIRONMENTAL SPECIFICATIONS
PARAMETER
SPECIFICATION
PHYSICAL
WEIGHT:
PACKED 46 Pounds (20.8 kg).
UNPACKED 38 Pounds (17.2 kg).
DIMENSIONS:
HEIGHT 5.25 Inches (13.3 cm).
WIDTH 17.70 Inches (44.9 cm).
DEPTH 19.00 Inches (48.3 cm).
ENVIRONMENTAL
AMBIENT OPERATING
TEMPERATURE
+32˚F to +122˚F (0˚C to +50˚C) Operational to -20˚C.
HUMIDITY 95% Maximum, Non-Condensing
ALTITUDE 0 to 15,000 Feet (4572 m) Above Sea Level.

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2INSTALLATION
This section contains information required for installation and preliminary checkout of the Broadcast Electronics
FX-50/E FM Exciters.
2.1 UNPACKING.
The equipment becomes the property of the customer when the equipment is delivered to the carrier. Carefully
unpack the exciter. Perform a visual inspection to determine that no apparent damage has been incurred during
shipment. All shipping materials should be retained until it is determined that the unit has not been damaged.
Claims for damaged equipment must be promptly filed with the carrier or the carrier may not accept the claim.
The contents of the shipment should be as indicated on the packing list. If the contents are incomplete, or if the
unit is damaged electrically or mechanically, notify both the carrier and Broadcast Electronics.
2.2 INSTALLATION.
Each exciter is assembled, operated, tested, and inspected at the factory prior to shipment and is ready for
installation when received. Prior to installation, this publication should be studied to obtain a thorough
understanding of the operation, circuitry, nomenclature, and installation requirements. Installation is
accomplished as follows: 1) Preliminary Installation, 2) Wiring, and 3) Exciter Checkout.
2.2.1 PRELIMINARY INSTALLATION.
ENVIRONMENTAL CONSIDERATIONS. Table 1-2 provides physical and environmental conditions which should
be considered prior to FX-50/E installation.
WARNING
WARNING
ENSURE ALL RACK POWER IS DEENERGIZED BE-
FORE ATTEMPTING EXCITER INSTALLATION.
AC LINE VOLTAGE PROGRAMMING. The FX-50/E exciters are programmed for the appropriate line voltage
when shipped from the factory. The FX-50E can only operate from a 240V ac supply. Therefore, ensure the line
voltage selector is configured to 240V.
For FX-50 models, the unit can be operated from a 110V or 220V ac supply. Check the ac line voltage
programming as follows:
Place the exciter on a work surface.
Remove any packing material from the outside of the exciter.
Refer to Figure 2-1 and ensure the appropriate primary ac line voltage is visible on the AC LINE VOLTAGE
SELECTOR circuit board (115/120V or 230/240V). The following text presents the ac line voltage programming:
LINE VOLTAGE VOLTAGE SELECTOR PROGRAMMING
97-115V 100V
115-133V 120V
194-230V 220V
230-266V 240V
CAUTION
CAUTION
THE FX-50E CAN ONLY OPERATE FROM A 240V AC SUPPLY.
THEREFORE, ENSURE THE LINE VOLTAGE SELECTOR IS
CONFIGURED TO 240V.

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©2011 Broadcast Electronics
Figure 2-1. FX-50/E REAR-PANEL CONNECTIONS (SHEET 1 OR 2)