Crown FM5 User manual

FM5 Transmitter
User's Manual
©2020 Crown Broadcast, a division of
International Radio & Electronics Corporation
2524 Toledo Road, Elkhart, Indiana, 46516, U.S.A. [phone]

Revision Control
Revision Print Date
Initial Release 2020
Important Notices
©2020, Crown Broadcast, a division of International Radio & Electronics Corporation.
Portions of this document were originally copyrighted by Michael P. Axman in 1994.
All rights reserved. No part of this publication may be reproduced, transmitted, transcribed,
stored in a retrieval system, or translated into any language in any form by any means
without the written permission of International Radio & Electronics Corporation.
Printed in U.S.A.
Crown Broadcast attempts to provide information that is accurate, complete, and useful.
Should you find inadequacies in the text, please send your comments to the following
address:
International Radio & Electronics Corporation
2524 Toledo Rd,
Elkhart, IN 46516 U.S.A.
ii

Contents
Section 1– Getting Acquainted 1-1
1.1 Your Transmitter 1-2
1.2 Applications and Options 1-3
1.2.1 Stand Alone 1-4
1.2.2 FM5, SDoC approved 1-4
1.3 Transmitter/Exciter Specifications 1-5
1.5 Safety Considerations 1-7
1.5.1 Dangers 1-7
1.5.2 Warnings 1-7
1.5.3 Cautions 1-7
Section 2– Installation 2-1
2.1 Operating Environment 2-2
2.2 Power Connections - AC & Fuse 2-2
2.3 Frequency (Channel) Selection 2-3
2.3.1 Modulation Compensator 2-4
2.4 RF Connections 2-5
2.5 Audio Input Connections 2-6
2.6 Audio Output Connections 2-6
2.7 Composite Input Connection 2-7
2.8 Audio Monitor Connections 2-8
2.9 Pre-emphasis Selection 2-8
Section 3-Operation 3-1
3.1PowerSwitch 3-2
3.2 Peak Modulation 3-3
3.3 Stereo-Mono Switch 3-3
3.4 Frequency Selector Switch 3-3
3.5 RF Output Control 3-4
Service&Support 4-1
Glossary G-1
iii

FM5 User’s Manual

Section 1—Getting Acquainted
This section provides a general description of the FM5 transmitter and
introduces you to safety conventions used within this document. Review
this material before installing or operating the transmitter.
1-1Getting Acquainted

1.1 Your Transmitter
The FM5 is a member of a family of FM stereo broadcast transmitters. Crown
transmitters are known for their integration, ease-of-use, and reliability.
The integration is most apparent in the standard transmitter configuration which
incorporates stereo generation and RF amplification without compromised signal quality.
Ease-of-use is apparent in the user-friendly front panel interface and in the installation
procedure. Simply select your operating frequency (using 5 external switches), add an
audio source, attach an antenna, and connect AC power and you're ready to broadcast.
Reliability is a Crown tradition. The first Crown transmitters were designed for rigors of
worldwide and potentially portable use. The modular design, quality components,
engineering approach, and high production standards ensure stable performance.
Illustration 1-1 FM5 Stereo Broadcast Transmitter
1-2 FM5 User’s Manual

1.2 Applications and Options
Crown transmitters are designed for versatility in applications. The FM5 can be used as a
stand-alone transmitter and in nearcast applications. The following discussion describes
these applications further.
Model numbers describe the configuration of the product (which has to do with its intended
purpose) and the RF output power which you can expect.
The number portion of the name represents the maximum RF output power. The FM5 gen-
erates up to 5 watts of RF output power
The FM5 is the standard or transmitter configuration. In this configuration, the product
includes the following components (functions):
 RF Exciter & Stereo Generator
 RF Low-Pass filter
 RF Amplifier
 Power Supply
Illustration 1–2 Standard (Transmitter) Configuration
1-3Getting Acquainted
RF Exciter & Stereo Generator
RF Low Pass
Filtering
Power Supply
RF Amplifier

1.2.1 Stand-Alone
In the standard configuration, the FM5 is an ideal stand-alone transmitter. When you add an
audio source (monaural, L/R stereo, or composite signal), an antenna, and AC power, the
transmitter becomes a complete FM stereo broadcast station, capable of serving your small
venue requirements, whether inside a church, outside in a parking lot, football stadium, race
track or drive-in-theater.
1.2.2 FM5, SDoC approved
The FM5 is an SDoC (Supplier Declaration of Conformity) approved transmitter. (Go to
ecfr.gov and do a simple search Title 47, 2.906) This means Crown Broadcast must send
with the transmitter a Proof of Performance that states this transmitter meets or exceeds the
FCC requirements for an FM transmitter.
This transmitter can be used with an FCC granted STA (Special Temporary License. Go to
ecfr.gov and do a simple search Title 47, 5.61) An application must be sent to the FCC, if
approved it would give a Special Temporary License at a specific frequency, for a specific
area, for no more than 6 months.
You could also turn this transmitter down to 1 watt and transmit in compliance with Part 15
requirements as long as your antenna does not broadcast outside 250 μV/m at 3 m. You
need to be aware that the FCC requires Part 15 Transmitters to be approved by the FCC
and this transmitter does NOT have Part 15 approval and could be subject to heavy FCC
fines for operating without a license. See 3.5 for suggestions on how to reduce the chances
that you are violating Part 15.
To find vacant channels in your zip code area, go to radio-locator.com and choose the va-
cant channels option. It will request the zip code of the area you are wishing to broadcast in
and will give you any vacant channel options - best, good, and ok.
The following was copied from fcc.gov website:
PenalƟes for OperaƟon Without A Permit or License
The Commission considers unauthorized broadcast operaƟon to be a serious maƩer. Pres-
ently, the maximum penalty for operaƟng an unlicensed or "pirate" broadcast staƟon (one
which is not permiƩed under Part 15 or is not a Carrier Current StaƟon or Campus Radio
StaƟon) is set at $10,000 for a single violaƟon or a single day of operaƟon, up to a total
maximum amount of $75,000.
Adjustments may be made upwards or downwards depending on the circumstances in-
volved. Equipment used for an unauthorized operaƟon may also be confiscated. There are
also criminal penalƟes (fine and/or imprisonment) for "willfully and knowingly" operaƟng a
radio staƟon without a license. DON'T DO IT!
1-4 FM5 User’s Manual

1.3 Transmitter/Exciter Specifications
Frequency Range 87.9 MHz–107.9 MHz
RF Power Output (VSWR 1.7:1 or better)
FM5 0-5.5 Watts adjustable
RF Output Impedance 50Ohms
Frequency Stability Meets FCC specifications from 0-50
degrees C
Audio Input Impedance 50k Ωbridging, balanced, or 600 Ω
Audio Input Level Selectable for –10 dBm to +10 dBm for
75 kHz deviation at 400 Hz
Pre-emphasis Selectable for 50, 75 µsec or flat
Audio Response Conforms to 75 µsec pre-emphasis
curveasfollows:
Complete Transmitter ±0.30 dB (50 Hz–10 kHz)
±1.0 dB (10 kHz–15 kHz)
Exciter only ±0.25 dB (50 Hz–15 kHz)
Distortion (THD + Noise)
Complete Transmitter Less than 0.7% (at 15kHz)
Exciter only Less than 0.3% (50Hz-15kHz)
Stereo Separation
Complete Transmitter Better than –40dB (50Hz-15kHz)
Exciter only Better than –40dB (50Hz-15kHz)
Crosstalk Main into Sub, better than –40dB
Sub into Main, better than –40dB
Stereo Pilot 19 kHz ±2 Hz, 9% modulation
1-5Getting Acquainted

Subcarrier Suppression 50dB below ±75 kHz deviation
FM S/N Ratio (FM noise)
Complete Transmitter Better than –60dB
Exciter only Better than –70dB
AM S/N Ratio Asynchronous and synchronous noise
better than FCC requirements
RF Bandwidth ±120 kHz, better than –35 dB
±240 kHz, better than –45 dB
RF Spurious Products Better than –70dB
Operating Environment Temperature (0°C to 50°C)
Humidity (0 to 80% at 20°C)
Maximum Altitude (3,000 Meters;
9834 Feet
AC Power 120 volts +10%/-15%); 50/60Hz
1-6 FM5 User’s Manual
Note: We set voltage and ampere requirements to assist you in designing your system. De-
pending on your operating frequency, actual requirements for maximum voltage and current
readings are 10–15% lower than stated.
Regulatory
FM5 Type notified FCC SDoC
Meets FCC, DOC, and CCIR requirements
Dimensions 27.94 x 41.91 x 2.54 cm
11 x 16.5 x 1 inches
Weight
FM5 2.7 kg (6 lbs)
3.6 kg (8 lbs) shipping weight