® FM30/FM100/FM250 Broadcast Transmitter User's Manual ©2005 Crown Broadcast, a division of International Radio and Electronics, Inc. 25166 Leer Drive, Elkhart, Indiana, 46514-5425 U.S.A.
Revision Control Revision Print Date Initial Release (Rev. 0; K80620–6) February 1995 Revision 1 (K80664–4) November 1995 Revision 2 (K80664A2) March 1996 Revision 3 (100885–1) October 1996 Revision 4 (100885–2) July 1997 Revision 5 (900194-1) October 1997 Revision 6 (130758-1) April 2000 Revision 7 April 2002 Revision 8 April 2005 Important Notices ©2005, Crown Broadcast, a division of International Radio and Electronics, Inc.
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 Backup ............................................................
Section 3—Operation ................................................. 3–1 3.1 Initial Power-up Procedures .............................................................................. 3–2 3.2 Power Switches................................................................................................. 3–4 3.2.1 DC Breaker .................................................................................................... 3–4 3.2.2 Power Switch ..............................................................
Section 5—Adjustments and Tests ................................. 5–1 5.1 Audio Processor Adjustments ........................................................................... 5–2 5.1.1 Pre-Emphasis Selection ................................................................................ 5–2 5.1.2 Pre-Emphasis Fine Adjustment ..................................................................... 5–2 5.2 Stereo Generator Adjustments ..........................................................................
Section 6—Reference Drawings .................................... 6–1 6.1 Views ................................................................................................................ 6–2 6.2 Board Layouts and Schematics ......................................................................... 6–4 Section 7—Service and Support .................................... 7–1 7.1 Service .............................................................................................................. 7–2 7.
I INFORMATION Section 1—Getting Acquainted This section provides a general description of the FM30, FM100, and FM250 transmitters and introduces you to safety conventions used within this document. Review this material before installing or operating the transmitter.
I 1.1 Your Transmitter The FM30, FM100, and FM250 are members 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 audio processing, stereo generation, and RF amplification without compromised signal quality. A single Crown transmitter can replace several pieces of equipment in a traditional system.
1.2 Applications and Options Crown transmitters are designed for versatility in applications. They have been used as stand-alone and backup transmitters and in booster, translator, satellator, and 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 each name represents the maximum RF output power.
I 1.2.1 Stand-Alone In the standard configuration, the FM30, FM100, and FM250 are ideal stand-alone transmitters. When you add an audio source (monaural, L/R stereo, or composite signal), an antenna, and AC or DC power, the transmitter becomes a complete FM stereo broadcast station, capable of serving a community. As stand-alone transmitters, Crown units often replace multiple pieces of equipment in a traditional setup (exciter, audio processor, RF amplifier). 1.2.
1.2.5 Translator A receiver configuration (FM100R, for example) replaces the audio processor and stereo generator boards with a receiver module. This added feature makes the FM30, FM100, and FM250 ideal for translator service in terrestrial-fed networks. These networks represent a popular and effective way to increase your broadcasting coverage. Translators, acting as repeater emitters, are necessary links in this chain of events.
I 1.2.6 Satellator One additional option is available for all configurations—an FSK Identifier (FSK IDer). This added feature enables the FM30, FM100, and FM250 to transmit its call sign or operating frequency in a Morse code style. This option is intended for use in satellite-fed networks. Transmitters equipped in this fashion are often known as "satellators.
1.3 Transmitter/Exciter Specifications Frequency Range 87.9 MHz–108 MHz (76 MHz–90 MHz optionally available) RF Power Output (VSWR 1.
I Subcarrier Suppression 50 dB below ±75 kHz deviation FM S/N Ratio (FM noise) Complete transmitter Better than –60 dB Exciter only Better than –70 dB 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 –70 dB Operating Environment Temperature (0o C –50o C) Humidity (0–80% at 20o C) Maximum Altitude (3,000 meters; 9843 feet) AC Power 100, 120, 220, or 240 volts (+10
Note: We set voltage and ampere requirements to assist you in designing your system. Depending on your operating frequency, actual requirements for maximum voltage and current readings are 10–15% lower than stated. Regulatory Type notified for FCC parts 73 and 74 Meets FCC, DOC, and CCIR requirements Dimensions 13.5 x 41.9 x 44.5 cm (5.25 x 16.5 x 17.5 inches) Weight FM30 10.5 kg (23 lbs) 13.6 kg (30 lbs) shipping weight FM100 11.4 kg (25 lbs) 14.5 kg (32 lbs) shipping weight FM250 16.
I 1.4 Receiver Specifications Monaural Sensitivity (demodulated, de-emphasized) 3.5 µV for signal-to-noise > 50 dB Stereo Sensitivity (19–kHz pilot frequency added) 31 µ V for signal-to-noise > 50 dB Connector Standard type N, 50 Ω Shipping Weight 1 lb 1.5 Safety Considerations Crown Broadcast assumes the responsibility for providing you a safe product and safety guidelines during its use.
® Section 2—Installation This section provides important guidelines for installing your transmitter. Review this information carefully for proper installation.
CAUTION Possible equipment damage! Before operating the transmitter for the first time, check for the proper AC line voltage setting and frequency selection as described in sections 2.2 and 2.3. 2.1 Operating Environment You can install the FM transmitter in a standard component rack or on a suitable surface such as a bench or desk. In any case, the area should be as clean and wellventilated as possible. Always allow for at least 2 cm of clearance under the unit for ventilation.
120Vac Illustration 2–1 Removing the Power Connector Cover rem befo ove drum re tu rn 120Vac 220Vac 240Vac Illustration 2–2 Selecting an AC Line Voltage Installation 2–3
2.2.2 Fuses The fuse holders are located in the power connector assembly just below the voltage selector. 120Vac 220Vac 240Vac rem befo ove drum re tu rn Illustration 2–3 Fuse Holder For 100 to 120 VAC operation, use the fuse installed at the factory. For 220 to 240 VAC operation, use the slow-blow fuse located in a hardware kit within the transmitter packaging. Consult the following table: Transmitter Input Power Fuse FM30 100–120 V 220–240 V 3A 1.5 A FM100 100–120 V 220–240 V 6.
2.2.3 Battery Power Your transmitter can operate on a DC power source (such as 3 or 4, 12–volt automotive batteries connected in series). The FM30 requires 28 volts DC for full output power, while the FM100 requires 36 volts, and FM250 requires 62 volts for full output power. Connect the batteries to the red (+) and black (–) battery input binding posts on the rear panel.
2. Locate the RF Exciter board and identify the frequency selector switches which will be used to change the setting. See Illustrations 2–6 and 2–7. Modulation Trim-pot Frequency Selection Rotary Switches RF Exciter FM250 ® Illustration 2–6 Top Cover Removed OPTIONAL MEGAHERTZ .1 .01 Illustration 2–7 RF Exciter Board (Frequency Selector Switches) 3. Use small flat blade screwdriver or another suitable device to rotate the switches to the desired setting.
2.3.1 Modulation Compensator The Modulation trim-potentiometer (see illustration 2–6) compensates for slight variations in deviation sensitivity with frequency. Set the trim-pot dial according to the following graph: Modulation Compensation Pot Setting 90 80 70 60 50 40 30 20 10 0 75 80 85 90 95 100 105 110 Frequency (MHz) Illustration 2–9 Modulation Compensator Settings These compensator settings are approximate. Each mark on the potentiometer represents about 1.8% modulation compensation.
2.4 Receiver Frequency Selection If you have a transmitter equipped with the receiver option, you will need to set the receiving or incoming frequency. 1. With the top cover removed, locate the receiver module and the two switches (labeled SW1 and SW2). Frequency Selection Switches Receiver Module ® FM250 Illustration 2–10 Receiver Module Switches 2. Use the adjacent chart to set the switches for the desired incoming frequency. 3. After setting the frequency, replace the top cover and screws.
Frequency SW1 SW2 Frequency SW1 SW2 Frequency SW1 SW2 Frequency SW1 SW2 87.9 88.0 88.1 88.2 88.3 88.4 88.5 88.6 88.7 88.8 88.9 89.0 89.1 89.2 89.3 89.4 89.5 89.6 89.7 89.8 89.9 90.0 90.1 90.2 90.3 90.4 90.5 90.6 90.7 90.8 90.9 91.0 91.1 91.2 91.3 91.4 91.5 91.6 91.7 91.8 91.9 92.0 92.1 92.2 92.3 92.4 92.5 92.6 92.7 92.8 92.9 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 1 9 1 9 1 9 1 9 1 9 1 9 1 9 1 9 1 9 1 93.0 93.1 93.2 93.3 93.4 93.5 93.6 93.7 93.8 93.9 94.0 94.1 94.2 94.
2.5 RF Connections Connect the RF load, an antenna or the input of an external power amplifier, to the type-N, RF output connector on the rear panel. VSWR should be 1.5:1 or better. WARNING Severe shock hazard! Do not touch the inner portion of the RF output connector when transmitter power is on. The RF monitor is intended primarily for a modulation monitor connection. Information gained through this connection can supplement that which is available on the transmitter front panel displays.
2.6 Audio Input Connections Attach audio inputs to the Left and Right XLR connectors on the rear panel. (The Left channel audio is used on Mono.) Pin 1 of the XLR connector goes to chassis ground. Pins 2 and 3 represent a balanced differential input with an impedance of about 50 kΩ. They may be connected to balanced or unbalanced left and right program sources. The audio input cables should be shielded pairs, whether the source is balanced or unbalanced.
2.7 SCA Input Connections You can connect external SCA generators to the SCA In connectors (BNC-type) on the rear panel. The inputs are intended for the 60 kHz to 99 kHz range, but a lower frequency may be used if the transmitter is operated in Mono mode. (The 23 to 53 kHz band is used for stereo transmission.) For 7.5 kHz deviation (10% modulation), input of approximately 3.5–volts (peak-to-peak) is required.
SCA IN RIGHT MONITOR COMPOSITE IN R LEFT/MONO L REMOTE I/O 1 2 3 + CIRCUIT BREAKER Composite In BNC Connector B A T T E R Y OFF – 36 VDC Audio Monitor Jacks Illustration 2–15 Composite In and Audio Monitor Connections 2.9 Audio Monitor Connections Processed, de-emphasized samples of the left and right audio inputs to the stereo generator are available at the Monitor jacks on the rear panel. The signals are suitable for feeding a studio monitor and for doing audio testing.
2.11 Program Input Fault Time-out You can enable an automatic turn-off of the carrier in the event of program failure. To enable this option, see illustration 2-17 on page 2-15. The time between program failure and carrier turn-off is set by a jumper (JP1) on the voltage regulator board (see page 6–17 for board location).
Pin Number Function 1 Ground 2 (no connection) 3 Composite Out (sample of stereo generator output) 4 FSK In (Normally high; pull low to shift carrier frequency approximately 7.5 kHz. Connect to open collector or relay contacts of user-supplied FSK keyer.) 5 /Auto Carrier Off (Pull low to enable automatic turnoff of carrier with program failure.) 6 Meter Battery (unregulated DC voltage; 5 volts = 50 VDC) 7 Meter RF Watts (1 volt = 100 watts) 8 Meter PA Volts (5 volts = 50 VDC) 9 /Ext.
Notes: 2–16 FM30/FM100/FM250 User's Manual
Section 3—Operation This section provides general operating parameters of your transmitter and a detailed description of its front panel display.
3.1 Initial Power-up Procedures These steps summarize the operating procedures you should use for the initial operation of the transmitter. More detailed information follows. CAUTION Possible equipment damage! Before operating the transmitter for the first time, check for the proper AC line voltage setting and frequency selection as described in sections 2.2 and 2.3. 1. Turn on the DC breaker.
3. Verify the following: a. The bottom cooling fan runs continuously. b. The Lock Fault indicator flashes for approximately 5 seconds, then goes off. 4. Set the Input Gain switches for mid-scale wideband gain reduction on an average program level (see section 3.4). 5. Set the Processing control (see section 3.5; normal setting is “50”). 6. Set the Stereo-Mono switch to Stereo (see section 3.6). 7. Turn on the Carrier switch. 8. Check the following parameters on the front panel multimeter: a.
3.2 Power Switches 3.2.1 DC Breaker The DC breaker, on the rear panel, must be on (up) for transmitter operation, even when using AC power. Electrically, the DC breaker is located immediately after diodes which isolate the DC and AC power supplies. 3.2.2 Power Switch The main on/off power switch controls both the 120/240 VAC and the DC battery power input. 3.2.
3.3 Front Panel Bar-Dot Displays Bar-dot LEDs show audio input levels, wideband and highband audio gain control, and modulation percentage. Resolution for the gain control and modulation displays is increased over a conventional bar-graph display using dither enhancement which modulates the brightness of the LED to give the effect of a fade from dot to dot. (See section 4.7.) 3.3.
3.4 Input Gain Switches The “+6 dB” and “+12 dB” slide switches set audio input sensitivity according to the following table. Nominal Input Sensitivity +10 dBm +4 dBm -2 dBm -8 dBm Switches +6 dB +12 dB Down Down Up Down Down Up Up Up Illustration 3–4 Input Gain Switches Find, experimentally, the combination of Input Gain switch settings that will bring the Wideband gain-reduction indicator to mid scale for “normal” level program material.
3.7 RF Output Control Set this control for the desired output power level. Preferably, set the power with an external RF wattmeter connected in the coaxial line to the antenna. You may also use the RF power reading on the digital multimeter. The control sets the RF output voltage. Actual RF output power varies as the approximate square of the relative setting of the control. For example, a setting of “50” is approximately 1/4 full power. 3.
PA DC Volts—Supply voltage of the RF power amplifier. PA DC Amps—Transistor drain current for the RF power amplifier. PA DC Temperature—Temperature of the RF power amplifier heatsink in degrees C. Supply DC Volts—Unregulated DC voltage at the input of the voltage regulators. For battery operation, this reading is the battery voltage minus a diode drop. Voltmeter—Reads the voltage at a test point located on the front edge of the motherboard.
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4.2 Audio Processor Circuit Board The audio processor board provides the audio control functions of a compressor, limiter, and expander. Illustration 6–5 and accompanying schematic may be useful to you during this discussion. Audio Processor Board FM250 Illustration 4–2 Audio Processor Board This board also contains the pre-emphasis networks. Reference numbers are for the left channel. Where there is a right-channel counterpart, references are in parenthesis.
uesto mondo, in rqse, uno si dice fo diciamo che se scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con ma scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con a m scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con madiciamo che se scrivendo con ma When either the positive or negative peaks of the output of U5 (U6) exceeds the gain-reduction threshold, U13A generates DC bias, producing broadband gain reduction.
Stereo Generator Board ® FM250 Illustration 4–3 Stereo Generator Board each with a Q of 5. The 38 and 19–kHz outputs of pins 1 and 20, respectively, are fairly pure sine waves. Harmonic distortion products are better than 66 dB down—THD of less than 0.05%. U212 is a precision, four-quadrant, analog multiplier. The output of U212 is the product of 38 kHz applied to the “X” input and the difference of left and right audio (L-R signal) applied to the “Y” input.
uesto mondo, in rqse, uno si dice fo diciamo che se scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con ma scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con a m scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con madiciamo che se scrivendo con ma 4.4 RF Exciter Circuit Board This board is also known as the Frequency Synthesizer board. The entire component side of the board is a ground plane.
Principles of Operation 4–7
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To get a direct reading of SWR, the reference input of the digital panel meter is fed from a voltage proportional to the forward-minus-reflected RF voltage, while forward-plus-reflected is fed to the digital panel meter input. The panel meter provides the divide function. U408 and U409 function as data selectors for the digital panel meter input and reference voltages. Binary select data for U408 and U409 comes from the display board.
uesto mondo, in rqse, uno si dice fo diciamo che se scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con ma scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con a m scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con madiciamo che se scrivendo con ma 4.
4.8 Voltage Regulator Circuit Board The voltage regulator board is the longer of two boards mounted under the chassis toward the front of the unit. It has switch-mode voltage regulators to provide +12, –12, and 20 volts. It also contains the program detection and automatic carrier control circuits. Illustration 6–11 and accompanying schematic complement this discussion. U703E and U703F convert a 38–kHz sine wave from the stereo generator into a synchronization pulse.
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4.11 RF Driver (FM100/FM250) The RF Driver assembly is mounted on a 100 mm x 100 mm plate in the under side of the chassis. The driver amplifies the approximate 20 milliwatts from the frequency synthesizer to about 8 watts to drive the RF power amplifier. An MHW6342T hybrid, high-gain, wideband amplifier, operating at about 20 volts, provides about one watt of drive to a single BLF245 MOSFET amplifier. The BLF245 stage operates from a supply voltage of approximately 20 volts.
uesto mondo, in rqse, uno si dice fo diciamo che se scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con ma scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con a m scrivendo con maquesto mondo, in se, uno si dice for diciamo che se scrivendo con madiciamo che se scrivendo con ma 4.13 Chassis The AC power supply components, as well as the bridge rectifier and main filter capacitor are mounted on the chassis.
4.15 Receiver Circuit Board Option This option allows the transmitter to be used as a translator. The receiver board receives terrestrially fed RF signal and converts it to composite audio which is then fed into the exciter board. Microprocessor controlled phase lock loop technology ensures the received frequency will not drift, and multiple IF stages ensure high adjacent channel rejection. Refer to illustrations 4–6, 6–16 and its schematic for the following discussion.
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Section 5—Adjustments and Tests This section describes procedures for (1) advanced users who may be interested in customizing or optimizing the performance of the transmitter and (2) service personnel who want to return the transmitter to operational status following a maintenance procedure.
5.1 Audio Processor Adjustments 5.1.1 Pre-Emphasis Selection Select the pre-emphasis curve (75 µsec, 50 µsec, 25 µsec, or Flat) by jumpering the appropriate pins of header JP1 on the audio processor board. (See section 2.9.) If you change the pre-emphasis, change the de-emphasis jumpers, JP203 and JP204 on the Stereo Generator board, to match. (See section 2.8.) 5.1.
Using a Modulation Monitor 1. Set the Stereo-Mono switch to Mono. 2. Check that the setting of the Modulation compensation control (see illustration 2–6) on the RF Exciter circuit board, falls within the range specified for the frequency of operation. (See section 2.3.1.) 3. Feed a sine wave signal of about 2.5 kHz into the left channel at a level sufficient to put the wideband gain-reduction indicator somewhere in the middle of its range. 4.
5.2.3 19–kHz Level Adjust the 19–kHz pilot for 9% modulation as indicated on an FM modulation monitor. (The composite output should be set first, since it follows the 19–kHz Level control.) 5.2.4 19–kHz Phase 1. Apply a 400–Hz audio signal to the left channel for at least 70% modulation. 2. Look at the composite stereo signal at TP301 on the RF Exciter circuit board with an oscilloscope, expanding the display to view the 19–kHz component on the horizontal centerline. 3.
5.3.4 FSK Balance Control An FSK signal (used for automatic identification of FM repeaters) shifts the frequencies of the 10.24–MHz crystal reference oscillator and the VCO. Use an oscilloscope to observe the cathode end of D306. With no program, the pulse will be less than 1 µsec wide. With an FSK input (a 20–Hz square wave at the FSK input will work), set trim pot R345 for minimum pulse width. The setting will vary slightly with operating frequency. 5.4 Metering Board Adjustments 5.4.
5.4.4 PA Current Limit Since it may not be practical to increase the PA current to set the PA Current Limit control, you may use this indirect method. With the carrier turned off, look at the DC voltage at the right end of R413 on the Metering board. The current limit, in amperes, will be 0.35 amps higher than ten times this voltage. For example, for a current limit of 7.35 amps, adjust the PA Current Limit control for 0.7 volts at R413 ; or 0.565 volts for 6.0 amps.
5.8 Bias Set (RF Power Amplifier) The Bias Set trim pot is located inside the PA module on the input circuit board. Set the trim pot to its midpoint for near-optimum bias. 5.9 Performance Verification Measure the following parameters to receive a comprehensive characterization of transmitter performance: ❑ Carrier frequency ❑ RF output power ❑ RF bandwidth and RF harmonics (see section 5.
5.10 Carrier Frequency Carrier frequency is measured at the output frequency with a frequency monitor or suitable frequency counter. To adjust frequency, see section 5.3.3. (FCC tolerance +/– 2000 Hz per FCC Part 73.1540 and 73.1545.) 5.11 Output Power The output power reading on the front panel display should be 90–105% of the actual value. For a more precise measurement, use a watt meter in the RF output line. See sections 5.4.1 and 5.4.2 for setting power. 5.
5.14 Audio Frequency Response For the response tests, take the readings from an FM modulation monitor. Make audio frequency response measurements for left and right channels at frequencies of 50 Hz, 100 Hz, 400 Hz, 1 kHz, 5 kHz, 10 kHz, and 15 kHz. See sections 5.9.1 and 5.9.2. 5.15 Audio Distortion Make distortion measurements from the de-emphasized output of an FM modulation monitor.
5.19.1 Main Channel Into Sub Feed the left and right channels in phase with audio (L+R) at 50 Hz, 100 Hz, 400 Hz, 1 kHz, 5 kHz, 10 kHz, and 15 kHz at 100% modulation, while observing the stereo subcarrier (L-R) level on an FM modulation monitor. 5.19.2 Sub Channel Into Main Feed the audio into the left and right channel as above, with the exception of reversing the polarity of the audio of one channel (L-R input). Using the frequencies of 5.19.
Section 6—Reference Drawings The illustrations in this section may be useful for making adjustments, taking measurements, troubleshooting, or understanding the circuitry of your transmitter.
6.
6.
R9 1K L VU C3 1.0 R2 1K L IN1 R4 24.9K 1 R6 24.9K 1 +12V C1 100PF L IN2 R8 30.1K 1 C4 1.0 L LP2 7 5 X 3 Y +5V 16 R11 47K 8 R VU R IN1 R40 1K R42 24.9K C13 100PF R IN2 C16 1.0 R41 1K 2 R43 24.9K 8 C18 .047 2 U4A TL072 1 3 7 4 7 9 4 1 C14 100PF R45 24.9K R33 10K D9 10 11 D8 R58 11.3K 1 3 D7 R61 24.9K R123 50K R66 49.9K 1 2 R119 4.7K R88 10M 10K 2 IN VO U17 4 GND +5V 4 U18A TL072 C38 1.0 5 C46 0.1 TRM R121 10.0K 1 R122 100 VSS -5V C39 1.
Illustration 6–6 Stereo Generator Board 6–6 FM30/FM100/FM250 User's Manual
+12V R54 24.9K 1% EXT RTN R55 24.9K C26 1.0 EXTERNAL COMPOSIT IN (3.5V P-P for 75KHz) 8 2 R56 24.9K EXT IN 1% 4 R57 24.9K C5 .0027 POLY 15.2 KHz LOW-PASS FILTER (8th ORDER ELLIPTICAL) LTC1064-1 1 2 3 4 5 6 7 LPIN L +6V U1 3 R7 3.65K 1% -6V R1 330 R38 1M C1 .0027 POLY 2 8 R5 1K R12 10.0K 1% U3A TL072 1 3 C6 1030PF R9 2K 1% +12V 4 R6 499 1% LPOUT L C? 100 pF C4 0 OHM +12V 2 14 13 12 11 10 9 8 D4 C3 100PF R3 0 OHM JP1 1 INPUT L D3 C27 1.0 -12V (3.5V P-P for 7.
SEE NOTE 10 TOP SIDE COMPONENT MAP, FM-VFM EXCITER UNCONTROLLED UNLESS OTHERWISE MARKED IN RED BY CM AS A CONTROLLED COPY, COPIES OF THESE DOCUMENTS AND ASSOCIATED ELECTRONIC FILES ARE UNCONTROLLED AND ARE FOR REFERENCE ONLY. THESE DRAWINGS, SPECIFICATIONS AND ASSOCIATED ELECTRONIC FILES ARE THE PROPERTY OF INTERNATIONAL RADIO AND ELECTRONICS CORP., AND SHALL NOT BE REPRODUCED, COPIED, OR USED AS THE BASIS FOR THE MANUFACTURE OR SALE OF APPARATUS OR DEVICES WITHOUT PERMISSION. M200440PT-A.
1 2 3 4 5 DWG. NO. 6 REV. 200440-SCH A 8 9 E . C . N. 10 11 REVISION HISTORY DESCRIPTION REV 12 DATE DWN 1 FOR PROTOTYPE 01-04-02 DW 2 MODIFIED PER MIKE SENEKI 02-06-02 DW 3 CHG'D R18 PER EAD MRH01. R18 WAS 91K OHM. U5 WAS C 6900-5 06-24-02 DW 246 A-G 4 R8 WAS 1.0K OHM. 05-23-03 DW 277 A PRODUCTION RELEASE 01-29-04 DW H APPROVALS CHK CM PE H DW DP 88-108 MHZ +8V +12V R24 150 +12V 2 MAR-6 C7 .
D 8169-1 Illustration 6-8 RF Metering Board 6–10 FM30/FM100/FM250 User's Manual
+12V PAV J2-4 C401 .01 R406 100K 1 Parts not loaded: 8 2 +5.00V U2 1 J4-3 REM PADCV 1.00V = 10VDC 3 C403, 404 DZ401 R402, 403, 404 Q401, 402 U401 LB401 R401 1N4148 D406 R409 100 4 -12V R410 100 5 (Jumper under board) C406 .01 R405 2.49K 1 J402 12 13 R416 100K R425 1M U405F 74HC14 U3 3 50mv per degree C. R422 75k R420 100K 1 C407 .
6 - 12 FM30/FM100/FM250 User's Manual
DWG. NO. 1 2 3 4 REV. 1 201207-SCH 5 6 7 8 9 5 E . C . N. HD7 FAN FAN+12V ALC / METERING HEADER 2 .156 H RF EXCITER U2 2 3 J2 J1 HD42 1 2 3 4 5 6 7 8 9 10 11 12 HEADER 12 +5.00V 1K HD31 HEADER 5 x 2 +12V DATE DWN 02-05-05 DW PE DW Vin NC GND 7 2 6 3 TRM TL072 1 U3A -12V +5.00V Z9 R43 OPEN 100 C51 5 H C52 .01 C50 1.0 +12V 8 C54 1.0 1.
Jumper FMA "E" Z1 Z2 Z3 Z4 Z5 Z6 Z7 Z8 Z9 Z10 Z11 Z12 Z13 Z14 Z15 Z16 Z17 Z18 Z19 Z20 Z21 Z22 Z23 Z24 Z25 Z26 Z27 Z28 Z29 Z30 Z31 Z32 Z33 JMP1 JMP2 Short Short Open Open Open Open Open Open Short Short Short Short Short Short Open Open Open Open Open Open Open Open Short Short Short Short Short Short Short Short Open Short Short Open Open FMA "T" 50K input Short Short Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Short Short Short Short Short Short Sho
R27 D 8167-5 Illustration 6-10 Display Board Reference Drawings 6 - 15
U602 LM3915 JP601 +12V R601 68K L VU R602 100K 8 R604 1.2K D601 1N4148 8 2 3 4 6 5 C602 1.0UF D602 1N4148 U601A TL072 7 5.00V R603 1K 1 C601 1.0UF 9 +12V 4 3 +12V 2 -12V 1 MODE RADJ DL601-610 +5V L8 DHI L7 IN L6 DLO L5 V- L3 L1 L2 YEL 12 G G DL621-625 16 GRN 18 L 2 L 1 C603 1.0UF R VU R607 68K R610 1.2K D603 1N4148 6 7 6 5.00V R609 1K 7 5 U601B TL072 9 8 5 C604 1.
Reference Drawings 6 - 17
1 2 3 4 5 DWG. NO. 6 REV. Q43229-6 AC 8 9 10 11 12 H H R1 4.7K CARR SW U3C R2 10.0K /CARRIER OFF 5 6 74HC14 R33 4.7K D1 1N4148 +12V VDD G G R3 4.7K U3A /AUTO CARRIER U3B 1 2 R4 10.0K R23 1.0K D2 1N4148 3 +6V 4 74HC14 VCC DZ1 1N4735 6.2V +12V R9 1.0K 16 D3 1N6263 U1A 2 R8 51K 1 7 TL074 4 12 R15 2.2K R14 220.0 +12V C27 0.1 COMP2 R16 10.0K RST 5 TL074 AUDIO or COMPOSITE D6 1N4148 U1B 6 3 R6 5.
Reference Drawings 6 - 19
1 2 3 4 5 6 REVISION HISTORY DESCRIPTION ON CHASSIS E . C . N. BATTERY ~ - DC INPUT + C1001 0.
R19 R20 Illustration 6-13 Power Amplifier-FM100/FM250 Reference Drawings 6 - 21
RF Output Amplifier RF OUTPUT AMPLIFIER 6 - 22 FM30/FM100/FM250 User's Manual
Illustration 6-14 RF Output Filter Reference Drawings 6 - 23
(455MHz) (195MHz) (176MHz) (252MHz) C1202 1.35PF C1204 7.1PF C1206 9.3PF C1208 5.13PF C1211 47PF NP0 R1202 * 75 R1203 10 RF OUT RF IN L1202 90.5NH L1201 250NH C1201 15.4PF C1201A 10PF L1203 94.1NH C1203 40.9PF C1217 3.5PF C1205 38.9PF C1209 14.1PF C1207 37.7PF C1209A 2PF R1201 100 D1201 1N6263 Approx. 7V RMS with 200W RF in. R1209 1K R1206 1K C1213 .001 I.D. L1201 0.25" L1202 0.5" L1203 L1204 L1205 GUAGE TURNS LENGTH 14 0.7" #17 3 0.6" #12 0.5" 3 0.5" #12 0.
Reference Drawings 6 - 25
1 2 3 4 5 E . C . N. REV 264 M 279 316 361 ADDED TO PWB (200922-PWB-D IN LOCATION SHOWN, AND DEPICTED ON COMPONENT MAP. F C23 6 C24 7 REVISION HISTORY DESCRIPTION 8 APPROVALS CHK CM DATE DWN PRODUCTION RELEASE 12-10-03 DW DW DP PE N XU1 WAS 200479-TERM-10 01-29-04 DW DW MH O PWB CHG'D TO REV. C 06-14-04 DW DW DP P PWB CHG'D TO REV. D 03-22-05 DW DW DP F .01 .
1 2 3 4 5 DWG. NO. 6 201069-SCH REV. A 8 9 E . C . N. 10 11 REVISION HISTORY DESCRIPTION REV A PRODUCTION RELEASE 12 DATE DWN 04-04-05 DW APPROVALS CHK CM PE DP H H BATTERY IN CB1001 CIRCUIT BREAKER ON MOTHER BOARD G 9 7 5 3 1 G 20 C0ND.
6 - 28 FM30/FM100/FM250 User's Manual
Reference Drawings 6 - 29
Section 7—Service and Support We understand that you may need various levels of support or that the product could require servicing at some point in time. This section provides information for both of these scenarios.
7.1 Service The product warranty (see opposite page) outlines our responsibility for defective products. Before returning a product for repair or replacement (our choice), call our Customer Service department using the following telephone number: (866) 262-8917 Our Customer Service Representative will give you further instructions regarding the return of your product. Use the original shipping carton or a new one obtained from Crown.
Crown Broadcast Three Year Limited Product Warranty SUMMARY OF WARRANTY Crown Broadcast, IREC warrants its broadcast products to the ORIGINAL PURCHASER of a NEW Crown Broadcast product, for a period of three (3) years after shipment from Crown Broadcast. All products are warranted to be free of defects in materials and workmanship and meet or exeed all specifications published by Crown Broadcast. Product nameplate with serial number must be intact and not altered in any way.
The following lists describe the spare parts kit available for your transmitter. For the FM100 and FM250, use part number GFMSPARES. The following parts are included: Item Quantity Fuse, 4A Slo-blo 5mmX20mm 6 Fuse, 6.3A Slo-blo 5mmX20mm 5 Fuse, 12.5A Slo-blo 5mmX20mm 5 15A 100V N-CH MOSFET 2 130V RMS 200V PEAK 6500A ZENER 2 35A 400V Bridge Rectifier 1 Diode, BYV72E–150 20A 150V 2 MOS Gate Driver, 500V IR #IR2125 2 MOSFET, RF Philips #BLF278 1 Switching Regulator, 0.
Factory Service Instructions To obtain factory service, complete the bottom half of this page, include it with the unit, and ship to: International Radio and Electronics Company, Inc. 25166 Leer Drive Elkhart, Indiana, U.S.A. 46514-5425 For units in warranty (within 3 years of purchase from any authorized Crown Dealer): We pay for ground UPS shipments from anywhere in the continental U.S. and Federal Express Second Day service from Hawaii and Alaska to the factory and back to you.
Appendix Transmitter Output Efficiency RF Power Output-FM 30 PADC Volts PADC Amps RF Power Efficiency 27.9 2.16 34 56 26.2 2.09 32 58 24.7 2.02 30 60 22.5 1.91 26 60 20.2 1.77 22 62 17.0 1.56 17 64 14.1 1.34 14 74 12.6 1.22 10 65 10.5 1.04 7 64 8.8 .88 5 65 6.6 .65 3 70 5.4 .53 2 70 Power measurements were made at 97.1 MHz. Voltage and current measurements were taken from the unit’s built-in metering.
Transmitter efficiency output RF Power Output-FM 100 PADC Volts PADC Amps RF Power Efficiency 31.2 5.72 110 61 29.6 5.35 100 63 26.4 4.55 79.4 66 23.5 3.90 63.1 68 21.1 3.40 50.1 69 19.0 2.97 39.8 70 17.1 2.63 31.6 70 15.4 2.35 25.1 69 13.9 2.10 20.0 68 12.5 1.90 15.8 66 11.2 1.74 12.6 64 10.1 1.62 10.0 59 9.1 1.52 7.9 57 Power measurements were made at 97.1 MHz. Return loss on the attenuators was greater than 30.
A B C Glossary The following pages define terms and abbreviations used throughout this manual.
A B C AF Audio Frequency; the frequencies between 20 Hz and 20 kHz in the electromagnetic spectrum. ALC Automatic Level Control AM Amplitude Modulation; the process of impressing information on a radio-frequency signal by varying its amplitude. bandwidth The range of frequencies available for signalling. BCD Binary-Coded Decimal; a digital system that uses binary codes to represent decimal digits.
FET Field-Effect Transistor frequency synthesizer A circuit that generates precise frequency signals by means of a single crystal oscillator in conjunction with frequency dividers and multipliers. FM Frequency Modulation; the process of impressing information on a radio signal by varying its frequency. FSK Frequency Shift Keying; an FM technique for shifting the frequency of the main carrier at a Morse code rate. Used in the on-air identification of frequencies.
A B C pre-emphasis The deliberate accentuation of the higher audio frequencies; made possible by a high-pass filter. processing The procedure and/or circuits used to modify incoming audio to make it suitable for transmission. receiver An option which adds incoming RF capability to an existing transmitter. See also "Translator." RF Radio Frequency; (1) A specific portion of the electromagnetic spectrum between audio-frequency and the infrared portion.
translator A transmitter designed to internally change an FM signal from one frequency to another for retransmission. Used in conjunction with terrestrial-fed networks. satellator A transmitter equipped with an FSK ID option for rebroadcasting a satellite-fed signal. VSWR Voltage Standing-Wave Ratio; see "SWR." Wideband See "broadband.
Index Symbols 19–kHz level adjustment 5–4 phase adjustment 5–4 booster transmitter use 1–4 broadband. See audio: broadband A C AC.
cooling fan 3–3, 3–8 control 4–9 coverage area 1–4 crosstalk 1–7 measurements 5–9 current limit PA 5–6 D DC. See power: input de-emphasis 2–13, 5–2, 5–7 jumpers 2–13 delay program failure to carrier turnoff 2– 14, 5–6 dimensions 1–9 display circuit description 4–10 front panel 3–3, 3–5, 3–7 modulation calibration 5–6 distortion 1–7 audio 5–9 harmonic 4–5 E emissions 5–8 exciter.
L labels 1–10 LEDs 3–5, 4–10 line voltage 2–2, 2–3 lock status 4–7 lock fault 3–8 M metering 1–2 circuit description 4–8 metering board adjustments 5–5 location 4–8 modulation 2–12, 3–5, 5–3, 5–7, 5–8 calibration 5–6 compensator 2–7 display 3–5 percentage 3–5, 5–9 monitor audio 2–13, 4–5 mono operation 2–12, 3–6 motherboard circuit description 4–9 multimeter 3–7 front panel 3–3 N nearcast transmitter use 1–6 networks satellite-fed 1–6 terrestrial-fed 1–5 noise 1–8, 3–8 measurements 5–9 O operating enviro
R (continued) input 1–5, 2–10 output 1–2, 1–5, 1–7, 3–3, 3–7 impedance 1–7 output filter 4–14 tuning 2–7 S safety 1–10 satellator transmitter use 1–6 SCA 1–5 input connection 2–12 sensitivity monaural 1–10 stereo 1–10 separation stereo 1–7 stereo generator 5–2 service warranty 7–3 Service Instructions 7–5 spares kit 7–4 specifications receiver 1–10 transmitter 1–7 stand-alone transmitter use 1–4 stereo separation 1–7, 5–9 stereo generator 1–2, 2–13 adjustments 5–2 board location 4–5 bypassing 2–12 circuit
