Broadcast Electronics Marti GTX Operating instructions

Broadcast Electronics
4100 North 24th Street, Quincy, Illinois 62305 USA • Phone [phone] • Fax [phone] • www.bdcast.com • [e-mail]
Marti GTX / GRX
BROADCAST STL
USER AND MAINTENANCE MANUAL
Revision 1.3
Mar 29, 2021

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©2021 Broadcast Electronics
GTX / GRX STL TRANSMITTER & RECIEVER
Technical Manual
©2021 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. 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.
Marti Electronics and the Marti logo are registered trademarks of Broadcast Electronics.
All other trademarks are property of their respective owners.
Copyright
Copyright laws protect artwork depicting circuitry in this manual.
Information in this manual is subject to change without notice and does not represent a commitment
on the part of Broadcast Electronics.
Broadcast Electronics may make improvements and/or changes in this manual or in the product
described herein at any time.
Broadcast Electronics Product Warranty (One-Year Limited)
Broadcast Electronics hereby warrants the Marti GTX & GRX products manufactured by Broadcast
Electronics against any defects in material or workmanship at the time of delivery thereof, or that
develop under normal use within a period of one (1) year from the date of shipment.
Broadcast Electronics reserves the right to repair equipment under warranty with new or
refurbished equipment or parts. Broadcast Electronics’ 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 Broadcast Electronics’ 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.

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(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 Broadcast Electronics
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. Broadcast Electronics 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 their new condition.
(d) “Resale Equipment”, defined as equipment purchased from another manufacturer or
supplier, then resold by Broadcast Electronics, shall only carry such manufacturer’s
or suppliers’ standard warranty in effect as of the original shipment date. All
warranty claims against any and all “resale equipment” sold by Broadcast
Electronics must be filed directly with the original equipment manufacturer.
Broadcast Electronics is unable to process or resolve equipment defects or
performance concerns on products or services not manufactured by Broadcast
Electronics.
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 Broadcast Electronics 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 Broadcast
Electronics, or if not installed according to Broadcast Electronics’ 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 Broadcast
Electronics’ 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. Broadcast Electronics shall not be liable for any expense of any nature
whatsoever incurred 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 BROADCAST
ELECTRONICS, 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.
Do not return any merchandise without first contacting Broadcast Electronics and receiving prior
written approval and a 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 the circumstances and reasons when requesting return of merchandise. 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. We can assume no liability for inbound damage, and necessary repairs become
the obligation of the shipper. All returned merchandise must be sent freight prepaid and properly
insured by the customer
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
(see next page.)
RF TECHNICAL SERVICES
Telephone: [phone]
E-Mail: [e-mail]
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: [e-mail]
Web Site: www.bdcast.com
PARTS

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Telephone: [phone]
E-Mail: [e-mail]
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.
SAFETY PRECAUTIONS
PLEASE READ AND OBSERVE ALL SAFETY PRECAUTIONS
DANGEROUS HAZARDS EXIST IN THE OPERATION OF POWER TRANSISTORS
The operation of 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 VOLTAGES & CURRENTS – AC mains voltages can be deadly. DC power
supplies and;/or batteries used in RF amplifier circuits can supply very high currents.
B. HOT SURFACES – Certain areas of the equipment, heat sinks and components may be
operating well above ambient temperature. In particular are the junction temperatures
of power transistors which can reach temperatures of several hundred degrees
centigrade and cause serious burns if touched
C. RF BURNS - RF power transistors and their circuits may contain high RF potentials. Do
not operate an RF power module with the covers removed.
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/cm2per one tenth hour average

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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.
IC RSS-GEN, Sec 8.3 Warning Statement-
(Required for Transmitters w/ detachable antennas)
ENGLISH:
This radio transmitter 131A-GTX900 has been approved by Industry Canada to operate with the
antenna types listed below with the maximum permissible gain and required antenna impedance
for each antenna type indicated. Antenna types not included in this list, having a gain greater
than the maximum gain indicated for that type, are strictly prohibited for use with this device.
FRENCH:
Le présent émetteur radio 131A-GTX900 a été approuvé par Industrie Canada pour fonctionner
avec les types d'antenne énumérés ci-dessous et ayant un gain admissible maximal et
l'impédance requise pour chaque type d'antenne. Les types d'antenne non inclus dans cette liste,
ou dont le gain est supérieur au gain maximal indiqué, sont strictement interdits pour
l'exploitation de l'émetteur.
Note: RF EXPOSURE SAFETY DISTANCE
RF Exposure Limits for Canada, according to IC regulation: setting to the maximum of the
output power of the apparatus, to guarantee the limits of exposure declared within this
document, it is necessary that the antenna gain used with this device should be 0dBi or less
and all persons should maintain a minimum separation distance of 0.4736 m (47.36 cm)
for general uncontrolled exposure and general controlled exposure.
For FCC standards, a safety distance of 0.4736 m (47.36 cm) is declared.
Limites d’exposition RF: en réglant au maximum de la puissance de sortie de l’appareil, afin
de garantir les limites d’exposition déclarées dans ce document, il est nécessaire que le
gain d’antenne utilisé avec cet appareil doit être de 0 dBi ou moins et toutes les personnes
doivent conserver une distance de séparation minimale de 47.36 cm pour les expositions
générales non contrôlées et les expositions générales contrôlées.

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Table of Contents
General Description ................................................................................................................................................9
Transmitter Review ............................................................................................................................................. 11
Receiver Review .................................................................................................................................................... 13
GTX and GRX Overall Data................................................................................................................................. 15
GTX Transmitter Only ......................................................................................................................................... 16
GRX Receiver Only ................................................................................................................................................ 17
Rack Mounting and Cooling.............................................................................................................................. 19
Control Functions.................................................................................................................................................. 19
GTX Parallel Remote............................................................................................................................................ 19
GRX Parallel Remote............................................................................................................................................ 20
Battery or DC Supply ........................................................................................................................................... 20
3.5.1 Notes on battery and wiring .................................................................................................................................. 20
Password Organization ...................................................................................................................................... 23
Factory Default Passwords ............................................................................................................................... 23
Display Menus and Navigation........................................................................................................................ 23
4.3.1 START & DEFAULT FIELDS ...................................................................................................................................24
•Timeouts and Default Fields ........................................................................................................................24
•Field INIT: Initialization Display ...............................................................................................................25
•Field #00: Escape / Default Display..........................................................................................................25
•Field #01: Operation / Setup Selection...................................................................................................25
•Field #20: Enter Password............................................................................................................................25
4.3.2 TRANSMITTER FIELDS & MENU TREE.............................................................................................................26
•OPERATION MENUS ........................................................................................................................................27
•Field #02: Direct & Reflected Power........................................................................................................27
•Field #04: Multiplex Signal Level (Output Modulation) ..................................................................27
•Field #05: Left & Right Signal Level in dB..............................................................................................27
•Field #06: L & R Signal Level / Analog Meter.......................................................................................27
•Field #07: RDS / SCA Auxiliary Modulation Level..............................................................................28
•Field #09: Internal Voltages.........................................................................................................................28
•Field #10: Temperature, Data and Clock................................................................................................28
•SETUP MENUS ....................................................................................................................................................29
•Field #21: Local/Remote control setup ..................................................................................................29
•Field #22: Transmission Frequency setup ............................................................................................29
•Field #23: Output Power setup...................................................................................................................29
•Field #24: LF Modulation Input Level setup.........................................................................................29
•Field #25: Auxiliary Input Level setup ....................................................................................................30
•Field #26: Limiter setup.................................................................................................................................30
•Field #27: Transmission Mode, and Pre-emphasis Setup...............................................................31
•Field #28: Reference Deviation setup......................................................................................................31
•Field #29: Display Contrast setup .............................................................................................................31
•Field #30: Time & Date setup......................................................................................................................31
•Field #31: Elapsed Time ................................................................................................................................31
•Field #32: Password Management............................................................................................................32
•Field #33: Alarm Setup and Display .........................................................................................................33
•Field #34: I/O Pin Allocation and Logic Level setup .........................................................................33

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•Field #35: Synthesis setup ............................................................................................................................34
•Field #37: Ethernet & Lan setup ................................................................................................................34
4.3.3 RECEIVER FIELDS & MENU TREE.......................................................................................................................35
•OPERATION MENUS ........................................................................................................................................36
•Field #02: Receiver Frequency ...................................................................................................................36
•Field #03: Received RF Field and Muting...............................................................................................36
•Field #04: MPX Modulation and Reception Field ...............................................................................36
•Field #04Modulation of the Multiplex Signal .......................................................................................36
•Fields #05 & #06: L and R Decoded Output Levels............................................................................36
•Field #08: Stereo Pilot Frequency level ..................................................................................................37
•SETUP MENUS ....................................................................................................................................................37
•Field #22: Frequency setup..........................................................................................................................37
•Field #24: LF Output Level setup...............................................................................................................37
•Field #25: Receiver Muting setup..............................................................................................................37
•Field #26: De-emphasis setup.....................................................................................................................38
•Field #28: Optional Boards Detection......................................................................................................38
•Field #33: Alarm setup and display..........................................................................................................39
•Field #34: I/O pin allocation and logic level setup ............................................................................39
•Field #36 Left & Right Level.........................................................................................................................40
•Field #37 Headphone Volume.....................................................................................................................40
•Field #39 Serial Number................................................................................................................................40
Transmitter Drawings......................................................................................................................................... 42
5.1.1 GTX Mechanical Layout – VHF & UHF Models ...............................................................................................42
Receiver Drawings................................................................................................................................................ 43
5.2.1 GRX Mechanical Layout – VHF & UHF Models ............................................................................................... 43

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Figures
Figure 1 – GTX Transmitter Block Diagram................................................................................................................ 11
Figure 2 – GTX Transmitter Rear Panel........................................................................................................................ 12
Figure 3 – GRX Rear Panel .................................................................................................................................................. 14
Figure 4 - GTX & GRX Remote Connectors .................................................................................................................. 19
Figure 5 – Transmitter Menu Tree.................................................................................................................................. 26
Figure 6 - Receiver Menu Tree.......................................................................................................................................... 35
Figure 7 – Transmitter Mechanical -VHF & UHF Models.................................................................................... 42
Figure 11 – Receiver Layout -VHF & UHF................................................................................................................. 43
Tables
Table 1 – Battery Life ............................................................................................................................................................ 22

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OVERVIEW Marti GTX / GRX
BROADCAST STL FAMILY SERIES
VHF / UHF & SHF Bands
General Description
The Marti GTX/GRX series STLs are the result of experience gained by Broadcast Electronics during
years of producing FM broadcast equipment, transmitters, STL and stereo encoders.
These radio links were specifically designed to comply with the latest international standards and
the requirements of advanced broadcasters, meeting tighter specifications than usually required, at
an affordable cost.
Great care was spent into producing a Hi-Fi-quality modulated signal, with low residual noise and
distortion. The RF signal is also free from spurious and harmonic components to a higher degree than
required by USA, CCIR, European, and most other national standards.
To obtain this outstanding performance, Broadcast Electronics strongly recommend relying on
qualified personnel to install and verify the equipment which makes up the radio station, i.e. the STL,
the transmitters and the power amplifiers, the corresponding antennas, cables and connectors. This
will assure to achieve the best performance and stability in time.
To this aim, Broadcast Electronics especially recommend that their equipment should not be
tampered with by unskilled personnel and its after-sale service is available to customers for any
technical problem. Before proceeding to installation, please carefully read at least the general
installation part of this manual, to gain confidence with the equipment.
This equipment is very stable and changes to the internal pre-setting other than frequency and few
other options are not usually required, however if they are, once again they must be done by skilled
personnel, with proper instrumentation and service documentation. Improperly tampering with the
settings may harm the apparatus or jeopardize the guaranteed performance.
THIS EQUIPMENT COMPLIES WITH ALL RELEVANT EMI/EMC AND SAFETY REQUIREMENTS, ETSI
EN300454-1/2 AND ETS301489-01/11 STANDARDS.
NO INTERNAL ADJUSTMENT OR PRESETTING IS REQUIRED DURING NORMAL OPERATIONS. THE
APPARATUS SHALL BE PROPERLY EARTHED AND OPERATED WITH ALL COVERS CLOSED WITH
ALL FASTENTERS TO PREVENT ELECTRICAL HAZARDS AND COMPLY WITH THE EMI & EMC
STANDARDS.

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The Marti GTX transmitter and its companion Marti GRX receiver are the core of a high quality,
synthesized studio-to-transmitter link (STL), to be used for broadcast repeaters in conjunction with
any standard FM or AM transmitter. They’re an evolution of the established Marti GTX/GRX series
STL whose main circuitry is still extensively used here with a new controller, user interface and
software and more advanced oscillators in a compatible 2RU, 19" case.
They allow the reception of mono or stereo signal and its retransmission without using any
additional stereo-coder on the receiving end: in both cases the LF output signal from the receiver
must be sent to the stereo input (linear or not pre-emphasized) of the local FM rebroadcast
transmitter.
The STL is built for several different frequency slots from VHF to the SHF range. Two main models
are built: one for the 200 - 960 MHz and the other frequencies in the SHF band. While the, controls,
basic circuitry and the performances are the same, some internal components vary or are specifically
tuned as required to cover this wide frequency band. Usually these components are the local
oscillator, the power amplifier and the input/ output filters. The factory adjusted frequency slots are
10 to 50 MHz wide and must be specified in the order. In the preset sub-range, the frequency and
power of the transmitter may be freely changed on the field. The receiver may require some more
adjustment for wider frequency displacement: in fact the adoption of narrow, low loss input filters
permitted to achieve the best possible rejection of interfering signals in the band at the expense of
some frequency agility. So nearly 8-10MHz may be used without any retouching but wider variation
up to 50-60MHz will require retuning of the input filter.
Being the apparatuses are completely digitally controlled, they are extensively on field
programmable by front panel or remotely in every respect. The alphanumeric display permits easy
and accurate metering, adjustment and continuous monitoring of modulation levels, power,
operation and internal parameters. All this information is externally available on the same RS232 I/O
port that maybe used to remotely control the transmitter. In addition to the serial I/O, some signals
and controls are available on a parallel I/O socket for easy interfacing with others analog controllers
or supervisory systems. A powerful 3-levels password management permits a very high degree of
security and privacy as may be required in different situations.
The LF input and output levels are precisely adjustable over a broad range, by means of 0.5dB
stepwise variable attenuators. The transmitter has also an auxiliary input, specifically designed for
RDS and SCA encoders. A modulation monitor output permits to control other transmitters or STL's
with the same internally processed high-quality mpx signal. Furthermore, the system is optimized to
be compatible with external digital companding encoder/decoders and to provide RDS and SCA
signals, with almost no attenuation.
Optional top-quality stereo encoder/decoder boards maybe factory installed on the transmitter/
receiver or field retrofitted with minimum required technical skill. The powerful internal software
and monitoring functions recognize their presence and enable the functions. A universal switch-
mode power supply permits operation in the extended 95-250 VAC range with no intervention and a
24 V back-up battery input is provided too.

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Transmitter Review
The transmitter and receiver set are fitted in the same sized cabinet and are nearly identical on the
front view. In fact they differ for the name on the front panel and the display and for the rear panel
connector's accommodation.
Both are clean and easy to control from the front panel through a single knob. The wide display and
simple self-explanatory menu allows navigation through the various options. A single fast push on
the jog knob acts as an "Enter" or confirmation while pushing for a longer time is interpreted as
"Escape".
Some LEDs signal at a glance proper functioning and warning states. Two red led signal warning
status, "Alarm" and "Limiter". A bi-stable yellow/green led signals "On the air" while a fourth one
signals "PLL Lock": both these two should be green in correct operation.
An RF Monitor output connector is located on the front panel for easy test on the field
An RF Circulator, aka Isolator, is used on models in the SHF band. The Isolator is not required on the
VHF/UHF bands
Figure 1 – GTX Transmitter Block Diagram

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Figure 2 – GTX Transmitter Rear Panel
All equipment inputs and outputs but RF monitor are located on the rear panel. They are:
1. The mains supply IEC320-type outlet, which incorporates the mains On/Off switch and
the fuses. The internal power supply operates in 115/230 VAC mains range without any
internal or external preset or switching.
2. An additional chassis screw for system earthing and a 24V-battery backup socket pair.
3. The RF antenna connector, N-type
4. The L & R stereo analog audio channels input on balanced XLR-type connectors (L input
is used only with internal Stereo Encoder option).
5. The AES/EBU stereo digital audio input on a balanced XLR-type connector which may be
used as an alternative to the analog input (this is a special option and may be used only
in conjunction with the internal Stereo Encoder option).
6. The wide-band external processed stereo or composite signal input on a grounded
unbalanced BNC connector
7. A frequency limited (20k100kHz) auxiliary channel input on a grounded, unbalanced
BNC connector for a RDS or SCA signal.
8. An LF modulation output for monitoring, RDS external synchronization or re-
broadcasting purpose, BNC-type
9. A RS232 Dsub9 female remote serial control port, inverted wired.
10. A parallel control port, Dsub9 male type

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Receiver Review
Like the Transmitter, the Receiver front panel accommodates the single control knob, the display,
four LEDs for immediate status control and a single output connector for IF monitoring.
Here too regular operation is signalized by green LEDs: "PLL Lock" and "Field". This latter is a bi-
stable and lights in yellow when RF field is too low or absent. As in the Transmitter red LEDs signals
improper operation. The first one, "Modulation", is activated by low or absent modulation; the last
one is the general "Alarm" LED.
Figure 3 – GRX Block Diagram

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Figure 3 – GRX Rear Panel
The Receiver I/O connectors on the rear panel are:
1. The mains supply IEC320-type outlet, which incorporates the mains switch and the
fuses.
2. An additional earth screw for system earthing and a 24V-battery backup socket pair.
3. The RF antenna connector, N-type
4. The main composite signal output (Mpx+, Mpx-) on two BNC-type connectors in
antiphase, permitting direct drive of two separate transmitters or one in balanced mode.
5. A buffered LF monitor, BNC-type connector that maybe internally connected as an
additional composite or wide-band or mono signal output.
6. The filtered/de-emphasized mono signal on a balanced male XLR-type connector.
7. The L & R audio channels output sockets on balanced XLR-type connectors only with
(Internal Stereo Decoder option).
8. A RS232 Dsub9 female remote serial control port, inverted wired.
9. A parallel control port, D-Sub 9 male type

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TECHNICAL SPECIFICATIOINS
GTX and GRX Overall Data
Frequency Ranges in MHz, specified on order
Model
Standard Freq Range (MHz)
Alternate Range (MHz)
GTX/GRX200
215-270
210-260
GTX/GRX300
300-360
310-370
GTX/GRX400
400-470
N/A
GTX/GRX800
830-854
850-900
GTX/GRX900
940-960
900-940
(Other ranges on request)
Modulation: FM 75kHz peak deviation.
180kF3E mono
256kF3E stereo
Synthesis Step
10kHz (215 – 960 MHz)
25kHz (1.3 – 2.5 GHz)
Composite Output Response:
+0.1/-0.5dB 15 Hz - 67 kHz
<-6 dB @ 100 kHz
<-20 dB @ 125 kHz
Monitor Output Wideband Response:
+0.1/-1.5dB 15 Hz ÷ 100 kHz
-3 dB typ. @ 125 kHz
-6 dB typ. @ 160 kHz
Mono/Stereo Response:
±0.2dB 0 Hz ÷ 15 kHz
S/N Ratio (30÷20000Hz RMS):
>75 dB, 80 typ. Mono
>72 dB, 76 typ. Stereo

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Modulation Distortion @ 100% dev
@ 1 kHz/
Mono ≤0.10% 0.03% typical.
Stereo, 1ch ≤0.30% 0.20% typical.
@ 30 - 7500 Hz
Mono ≤0.25% 0.12% typical.
Stereo, 1ch ≤0.30% 0.20% typical.
Stereo Crosstalk:
>50 dB 400 - 10000 Hz, typical
>40 dB 100 - 15000 Hz, typical
Input/Output:
Alarm RF/LF disable, Low RF field
Remote Control/Lock
RS232 for Monitoring and Control
Power Input Requirements:
95 / 250 VAC 50/60 Hz
22.0 - 28.0 VDC
Operating Temperature Range:
0 - 35° C recommended.
-10 - 45° C max.
GTX Transmitter Only
Frequency Error: <2,5 ppM
Frequency Drift: <1 ppM/year
RF Output Power: 7W / 15W (215÷960 Mhz)
2W / 5W (1.4÷2.6 Ghz)
Max Ref Pwr Allowed: 1W / 2W
RF Harmonics: <-60 dBc
RF Spurious: <-70 dBc, -80 dBc typ.
RF Output: 50 ohm, N connector
Audio/Input Level: -3.5 ÷ +12.5dBm
@ ± 75kHz deviation
Audio/Input: 10k ohm/600 ohm, bal./unbalanced
Common Mode Rejection: >50 dB, >60dB typ. (20÷15000 Hz)
Audio Input Connectors: Female XLR
Auxiliary Input Level: -12.5 ÷ +3.5dBm @±7.5 kHz dev.
-24 ÷ -8dBm @±2 kHz dev.
Auxiliary Input: 10k ohm / BNC-type
Monitor LF Output: 0 ÷ +10 dBm @ ±75kHz dev.
Pre-emphasis 0/50/75 μs ±2%
S/N, 30 Hz – 20kHz >77 dB, 82 typ. Mono
>74 dB, 77 typ. Stereo

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Distortion, 30Hz – 15kHz: <0.02% @ 75kHz dev.
Stereo Crosstalk: >50 dB (100÷5000 Hz)
>45 dB (50÷15000 Hz)
Audio Response,
30Hz - 15 kHz: ±0.1dB
Out of Band Audio Attenuation:
>50 dB @ F≥19 kHz
Deviation Limiter: 0 - +7.1 dB, adjustable
Composite Response:
10 Hz÷100kHz ±0.1dB
Auxiliary Response:
10÷ 100 kHz ±0.2dB
Power Input: 50 W max @ 90/250Vac (Po= 5W)
80 W max @90/250Vac (Po=15W)
Battery Input: ≤1.8A @ 24 Vdc (Po= 5W)
≤3.0A @ 24 Vdc (Po= 15W)
Dimensions, less handles: 19" 2RU,
19.0 x 3.46 x 12.6 in
483 x 88 x 330mm
GRX Receiver Only
Receiver Noise: ≤9 dB
Image Frequency Rejection: ≥60 dB 70 typ.
Dynamic Selectivity: >+10dB typ @ δF=300 kHz
>+35dB typ @ δF=500 kHz
>+45dB typ @ δF=1.0 MHz
AM Suppression: >45 dB
Usable Input Level: -90 ÷ -10dBm, (7μV÷70mV)
Sensitivity (typical): Sin= -90dBm (7μV) Mono
(S/N=60dB) Sin= -70dBm (70μV) Stereo
IF Monitor Output: 10.7 MHz / 0dBm
Mono or Stereo Decoded Response:
30 Hz ÷ 15 kHz ±0.1dB
Out of band Mono or Stereo Audio Response:
>50 dB @ F≥19 kHz
De-emphasis Time Constant: 0/50/75μs ±2%
S/N Ratio, (30÷20000 Hz. rms):
>72 dB, 76 typ. mono
>70 dB, 73 typ. stereo

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©2021 Broadcast Electronics
Distortion @ 1kHz / 100% dev.
- Mono ≤0.1%, 0.03% typ.
Stereo ≤0.3%, 0.20% typ.
Stereo Crosstalk: >50 dB (100÷5000 Hz)
>45 dB (50÷15000
Power Input: 15 W max @ 90/250Vac
Battery Input: ≤0.4A @ 24 Vdc
Dimensions, less handles: 19" 2RU,
19.0 x 3.46 x 12.6 in
483 x 88 x 330 mm