R and L Media Systems PM300 FM Broadcast Radio Transmitter User Manual PM300 R2 0 24 06 2004

R & L Media Systems Inc FM Broadcast Radio Transmitter PM300 R2 0 24 06 2004

PM300 Manual

Download: R and L Media Systems PM300 FM Broadcast Radio Transmitter User Manual PM300 R2 0 24 06 2004
Mirror Download [FCC.gov]R and L Media Systems PM300 FM Broadcast Radio Transmitter User Manual PM300 R2 0 24 06 2004
Document ID526941
Application IDodiQRoidVIL1/SumSOXkvw==
Document DescriptionPM300 Manual
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Permanent ConfidentialNo
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Document TypeUser Manual
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Date Submitted2005-03-26 00:00:00
Date Available2005-05-04 00:00:00
Creation Date2005-01-20 08:30:39
Producing SoftwareAcrobat Distiller 5.0 (Windows)
Document Lastmod2005-01-20 08:34:41
Document TitlePM300 R2.0 24/06/2004
Document CreatorAcrobat PDFMaker 5.0 for Word
Document Author: db

DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
FM Broadcasting Transmitter
User’s Manual
Release 2.0
- DB ELETTRONICA TELECOMUNICAZIONI S.p.A. - Via Lisbona, 38 - 35127 Z.I. SUD PADOVA ITALY -- Ph. (049) 870-0588 - Fax. (049) 870-0747 -
- http://www.dbbroadcast.com -
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
SAFETY NOTICES
WARNING
To avoid risks of electrical shocks or fire, only qualified personnel should execute the procedures
specified in this manual.
WARNING
When the protective covers of any device or component connected to a 110 / 240 VAC source by a
power cord are removed, voltages and currents dangerous to life may be exposed.
WARNING
Contact with 110 / 240 Volts of alternating current and associated direct current and voltages can be
fatal.
DANGEROUS
RISK OF ELECTRICAL SHOCK DO NOT OPEN
CAUTION
To reduce the risks of electrical shock, do not remove the cover (or the back). Refer, for servicing,
to qualified service personnel. This installation should be done by a qualified person and should
comply with to all local applicable laws.
NOTICE: ALL THE SPECIFICATIONS AND TECHNICAL INFORMATION IN THIS MANUAL ARE
SUBJECT TO CHANGE WITHOUT NOTICE.
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INDEX
1.
PM300 FM TRANSMITTER...................................................................................................................6
1.1 GENERAL DESCRIPTION ................................................................................................................6
2. TECHNICAL SPECIFICATIONS........................................................................................................11
3. INSTALLATION ....................................................................................................................................13
4. FREQUENCY SETTING.......................................................................................................................14
5. ADJUSTMENTS AND MEASURES ....................................................................................................16
6. POWER SUPPLY SECTION ................................................................................................................18
6.1 GENERAL DESCRIPTION ..............................................................................................................18
6.2 SWITCHING POWER SUPPLY MODULE PART LIST................................................................22
6.3 EQUIP. PWR SUPP. BOARD PARTS LIST (DB 0206_090)..........................................................31
6.4 DB 0201_070 PRINTED BOARD PARTS LIST .............................................................................35
7. MODULATION STAGE (SINTEL 96).................................................................................................36
7.1 GENERAL DESCRIPTION ..............................................................................................................36
7.2 “SINTEL 96” MODULATOR PARTS LIST ....................................................................................44
8. AMP30 DRIVER STAGE ......................................................................................................................47
8.1 GENERAL DESCRIPTION ..............................................................................................................47
8.2 AMP30 PRE AMPLIFIER PARTS LIST..........................................................................................50
9. RF AMPLIFIER STAGE .......................................................................................................................51
9.1 AMP300 AMPLIFIER BOARD ........................................................................................................51
9.2 AMP300 AMPLIFIER PARTS LIST ................................................................................................54
9.3 LOW PASS FILTER AND DIRECTIONAL COUPLER .................................................................55
9.4 L. P. FILTER AND DIR. COUP. PARTS LIST................................................................................56
10. PROTECTION STAGE......................................................................................................................57
10.1 PROTECTION /CONTROL STAGE N°1 PARTS LIST.................................................................67
10.2 PROTECTION /CONTROL STAGE N°2 PARTS LIST.................................................................74
11. METER STAGE ..................................................................................................................................75
11.1 GENERAL DESCRIPTION ..............................................................................................................75
11.2 MICROPROCESSOR BOARD PARTLIST .....................................................................................78
11.3 DISPLAY BOARD PARTS LIST .....................................................................................................81
12. IN-AUDIO BOARD.............................................................................................................................82
12.1 IN-AUDIO BOARD PARTS LIST....................................................................................................84
12.2 IN-AUDIO BOARD JUMPERS SETTING ......................................................................................85
13. STEREO ENCODER BOARD (OPTION) .......................................................................................86
13.1 CHANNELS PRE- EMPHASIS SETTING ......................................................................................86
13.2 STEREO ENCODER PARTS LIST..................................................................................................98
14. CONTRAVES BOARD (OPTION) .................................................................................................101
14.1 GENERAL DESCRIPTION ............................................................................................................101
14.2 CONTRAVES BOARDS PARTS LIST..........................................................................................103
15. TROUBLESHOOTING....................................................................................................................104
16. APPENDIX A.....................................................................................................................................106
16.1 XLR AUDIO CONNECTORS PINOUTS ......................................................................................106
17. APPENDIX B.....................................................................................................................................107
17.1 MOSFET REPLACEMENT............................................................................................................107
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FIGURES INDEX
FIG. 1.1 - FRONT VIEW....................................................................................................................................8
FIG. 1.2 - REAR VIEW ......................................................................................................................................9
FIG. 1.3 - TOP VIEW .......................................................................................................................................10
FIG. 4.1 - CONTRAVES WEIGHT .................................................................................................................14
FIG. 6.1 - SWITCHING POWER SUPPLY MODULE ELECTRICAL SCHEMATIC “A” ..........................19
FIG. 6.2 - SWITCHING POWER SUPPLY MODULE ELECTRICAL SCHEMATIC “B” ..........................20
FIG. 6.3 - SWITCHING POWER SUPPLY MODULE COMPONENT LAYOUT........................................21
FIG. 6.4 – EQUIP. PWR SUPP. BOARD GENERAL ELECTRICAL SCHEMATIC....................................26
FIG. 6.5 - EQUIP. PWR SUPP. BOARD +24 V STAGE ELECTRICAL SCHEMATIC ...............................27
FIG. 6.6 - EQUIP. PWR SUPP. BOARD-12V STAGE ELECTRICAL SCHEMATIC ..................................28
FIG. 6.7 - EQUIP. PWR SUPP. BOARD +12V STAGE ELECTRICAL SCHEMATIC ................................29
FIG. 6.8 - EQUIP. PWR SUPP. BOARD COMPONENT LAYOUT (DB 0206_090) ....................................30
FIG. 6.9 - DB 0201_070 PRINTED BOARD ELECTRICAL SCHEMATIC..................................................33
FIG. 6.10 - DB 0201_070 PRINTED BOARD COMPONENT LAYOUT......................................................34
FIG. 7.1 - “SINTEL 96” MODULATION BOARD GENERAL ELECTRICAL SCHEMATIC ....................37
FIG. 7.2 - PLL STAGE ELECTRICAL SCHEMATIC....................................................................................38
FIG. 7.3 - VCO STAGE ELECTRICAL SCHEMATIC ..................................................................................39
FIG. 7.4 - LF 1 STAGE ELECTRICAL SCHEMATIC ..................................................................................40
FIG. 7.5 - LF 2 STAGE ELECTRICAL SCHEMATIC ..................................................................................41
FIG. 7.6 - FILTER STAGE ELECTRICAL SCHEMATIC .............................................................................42
FIG. 7.7 - “SINTEL 96” MODULATION COMPONENT LAYOUT (DB 9604-010) ...................................43
FIG. 8.1 - AMP30 PRE AMPLIFIER ELECTRICAL SCHEMATIC..............................................................48
FIG. 8.2 - AMP30 PRE AMPLIFIER COMPONENT LAYOUT (DB 0110_010A) .......................................49
FIG. 9.1 - AMP300 AMPLIFIER ELECTRICAL SCHEMATIC ....................................................................52
FIG. 9.2 - AMP300 AMPLIFIER COMPONENT LAYOUT (DB 9812_001) ................................................53
FIG. 9.3 - L. P. FILTER AND DIR. COUP. ELECTRICAL SCHEMATIC....................................................55
FIG. 9.4 - L. P. FILTER AND DIR. COUP. COMPONENT LAYOUT (DB 9611-005) ................................56
FIG. 10.1 - PROTECTION /CONTROL STAGE N°1 GENERAL SCHEMATIC ........................................59
FIG. 10.2 - UNBALANCING PROTECTION STAGE ...................................................................................60
FIG. 10.3 - FWD PROTECTION STAGE........................................................................................................61
FIG. 10.4 - TEMPERATURE PROTECTION STAGE ...................................................................................62
FIG. 10.5 - POWER LIMITING STAGE .........................................................................................................63
FIG. 10.6 - PROTECTION /CONTROL STAGE N°1 COMPONENT LAYOUT (DB 9702_004)...............66
FIG. 10.7 - PROTECTION /CONTROL STAGE N°2 GENERAL SCHEMATIC.........................................68
FIG. 10.8 - PROTECTION STATUS STAGE .................................................................................................69
FIG. 10.9 - POWER SUPPLY STAGE ............................................................................................................70
FIG. 10.10 - MEASURES ADJ. STAGE..........................................................................................................71
FIG. 10.11 - LED INDICATIONS STAGE ......................................................................................................72
FIG. 10.12 - PROTECTION /CONTROL STAGE N°2 COMPONENT LAYOUT (DB 9703_011).............73
FIG. 11.1 - MICROPROCESSOR STAGE ELECTRICAL SCHEMATIC (DB 9903_040) ...........................76
FIG. 11.2 - MICROPROCESSOR BOARD COMPONENT LAYOUT (DB 9903_040) ................................77
FIG. 11.3 - DISPLAY STAGE ELECTRICAL SCHEMATIC (DB 9903_050) ..............................................79
FIG. 11.4 - DISPLAY BOARD COMPONENT LAYOUT (DB 9903_050) ...................................................80
FIG. 12.1 - IN-AUDIO BOARD ELECTRICAL SCHEMATIC......................................................................82
FIG. 12.2 - IN-AUDIO BOARD COMPONENT LAYOUT (DB 9909_010)..................................................83
FIG. 13.1 - STEREO ENCODER GENERAL SCHEMATIC..........................................................................87
FIG. 13.2 - L/R PEAK DETECTOR STAGE ELECTRICAL SCHEMATIC .................................................88
FIG. 13.3 - INPUT STAGE ELECTRICAL SCHEMATIC .............................................................................90
FIG. 13.4 - RIGHT FILTER STAGE ELECTRICAL SCHEMATIC ..............................................................91
FIG. 13.5 - LEFT FILTER STAGE ELECTRICAL SCHEMATIC.................................................................92
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FIG. 13.6 - OSCILLATOR STAGE ELECTRICAL SCHEMATIC ................................................................93
FIG. 13.7 - 19 KHZ STAGE ELECTRICAL SCHEMATIC.............................................................................94
FIG. 13.8 - 38 KHZ STAGE ELECTRICAL SCHEMATIC.............................................................................95
FIG. 13.9 - OUTPUT STAGE ELECTRICAL SCHEMATIC .........................................................................96
FIG. 13.10 - STEREO ENCODER COMPONENT LAYOUT (DB 9506-001)...............................................97
FIG. 14.1 - CONTRAVES BOARD ELECTRICAL DIAGRAM ..................................................................102
FIG. 14.2 - CONTRAVES BOARD COMPONENT LAYOUT (DB 9308-020)...........................................103
FIG. 17.1 - MOSFET REPLACEMENT ........................................................................................................108
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1. PM300 FM TRANSMITTER
1.1 GENERAL DESCRIPTION
The PM300 is a FM broadcasting transmitter with continuously adjustable output power, 0
to 300W.
They can be used as stand-alone complete transmitters or as drivers for high power
amplifiers.
The PM300 transmitter is built with MOS transistor technology.
On the PM300 the use of MOSFET yields:
- Higher efficiency (about 85%);
- High gain (high transconductance and low internal reactive capacitance);
- High thermal stability (negative coefficient for drain current).
The output frequency range is between 87.5 and 108 MHz. Frequency setting is made using
internal dip switches or contraves on front panel (/C option). The minimum frequency step
is 10 kHz.
The /S option has a built-in digital stereo coder with stereo separation in excess of 65 dB
and a SNR of more than 80 dB.
The /P option includes a stereo audio processor with a wide range compression threshold,
attack and release time adjustments and full compatibility with digital audio mixing
consoles.
The /R option consists of full remote control capability with remote adjustments and
checks for all main parameters: power output adjustment, ON/OFF command, protections
reset, forward and reflected power measure, frequency deviation measure and alarms
status.
The /FSK option makes the PM300 transmitter fully compatible with the FCC automatic
identification system.
The /VDC option provides battery operation.
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The transmitters have high frequency stability, due to the use of the Digital Phase Locked
Loop system and very low drift reference quartz.
An internal deviation limiter controls the maximum frequency deviation, thus avoiding
adjacent channel interference in case of accidental over modulation. In order to limit over
modulation, it is necessary to insert the jumper jp6 on the modulation board (see Fig. 7.7).
Valuable characteristics of PM transmitters include intelligent protection circuits to prevent
load mismatching (VSWR), to prevent over-temperature (TEMP) and provide an
unmatched durability.
On the front panel every alarm condition is monitored by LEDS.
The multiple led indicators of the front panel enable the full, easy and fast verification of
all the main parameters and condition of operation. The output power, the reflected power,
the voltage supply of the power amplifier, the frequency deviation, L & R, and MPX are
continuously monitored.
It is possible, using the front panel adjustments, to control the following settings: output
power (PWR adj.), frequency deviation (DEV adj.), transmitting frequency (option /C),
manual /remote control selection (option /R) and the mono /stereo selection (option /S).
An output LP filter ensures a pure RF spectrum, compatible with the most stringent
international requirements. As well, a high efficiency switching mode power supply
reduces the power consumption, and ensures reliable operation.
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Fig. 1.1 - FRONT VIEW
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Fig. 1.2 - REAR VIEW
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Fig. 1.3 - TOP VIEW
1) Remote control board (option)
2) Equipment Power Supply Board
3) Low Pass Filter Board
4) AMP300 RF Amplifier Board
5) AMP30 Driver Board
6) Ventilation System
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7) IN-AUDIO Board
8) “Sintel 96” Modulator Board
9) Stereo Encoder Board
10) Switching power supply module (PBIT2180)
11) Meter and microprocessor boards
12) Protection boards (N°1, N°2)
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2. TECHNICAL SPECIFICATIONS
Output frequency range...............................................................................................87.5 to 108 MHz
Output frequency setting ..................................... synthesized with internal dip switches, 10 kHz step
or synthesized by contraves on front panel (/C option)
Output impedance .......................................................................................................................... 50 W
Output connector................................................................................................................................. N
Output power........................................................................................................................ 0 to 300 W
Harmonics ...................................................................................................................... £-80 dB (Typ.)
Spurious .......................................................................................................................... £-85 dB (Typ)
Syncro AM modulation............................................................................................................. £-55 dB
Asyncro AM modulation........................................................................................................... £-60 dB
Frequency stability
Vs. Line Voltage (±15%) ......................................................................................................... ± 0.7 Hz
Aging drift..................................................................................................................... ± 300 Hz / year
MODULATION
Mono operation
Input level -6 to +10 dBm
Input connector............................................................................................................... XLR balanced
Input impedance .......................................................................................................................... 600 W
Bandwidth (± 0.25 dB).................................................................................................20 Hz to 15 kHz
Attenuation of frequencies ³ 19 kHz ......................................................................................... ³50 dB
Preemphasis ..........................................................................................................................50/75 msec
S/N ratio (± 75 kHz peak dev. with 1 kHz input, 50ms deemphasized).................................... ³75 dB
THD+N (± 75 kHz peak dev. with 1 kHz input, unweighted).....................................................£0.1%
Stereo operation (with stereo coder included in /S model)
L & R input level ...........................................................................................................-6 to +10 dBm
Input connectors .............................................................................................................. XLR balanced
Input impedance .......................................................................................................................... 600 W
Bandwidth (± 0.25 dB).................................................................................................20 Hz to 15 kHz
Attenuation of frequencies ³ 19 kHz ........................................................................................ ³50 dB
Preemphasis ..........................................................................................................................50/75 msec
S/N ratio (± 75 kHz peak dev. with 1 kHz input, 50ms deemphasized)..................................... ³70 dB
THD+N (± 75 kHz peak dev. with 1 kHz input, unweighted).....................................................£0.1%
Stereo separation ........................................................................................................................ ³60 dB
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Stereo operation (with external stereo coder)
MPX input level ..............................................................................................2.2 Vpp per 75 kHz dev.
Input connector ..............................................................................................................................BNC
Input impedance ........................................................................................................................... 10 kW
Bandwidth (± 0.25 dB)..............................................................................................20 Hz to 100 kHz
POWER REQUIREMENTS
Operating voltage ............................................................................... 110/220 VAC ± 10 %, 50/60 Hz
Power consumption (at max. output power) ............................................................................. 550 VA
Battery operation (option /VDC) ........................................................................................2 x 24 VDC
OPERATING CONDITIONS
Cooling....................................................................................................air forced, 24 VDC axial fans
Temperature range ............................................................................................................-5° to +45° C
Humidity ................................................................................................................................95% max.
WEIGHT AND DIMENSION
Weight (Kg) ...................................................................................................................................... 16
Dimension (W x H x D) mm........................................................................................ 483 x 132 x 513
OPTIONS
External frequency setting ................................................................................................................ /C
Stereo coder ....................................................................................................................................... /S
Audio processor ................................................................................................................................ /P
Remote control ................................................................................................................................. /R
Battery operation ......................................................................................................................... /VDC
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3. INSTALLATION
To install the PM300 transmitter:
1. Control that the main ON /OFF switch on the rear panel is in the OFF position (labeled “0”).
2. Set the correct main supply voltage (220 Vac or 115 Vac) using the PWR supply selector.
3. Connect an antenna or a dummy load to the RF power output connector.
4. Connect the transmitter to the main power supply using the power cord included.
5. Switch ON the transmitter: on the front panel you will see the “ON” led light
(If the led remains OFF refer to the TROUBLESHOOTING section).
6. Control that the “LOCK” led on the front panel lights up a few seconds after the power is turned on.
If it is not, please refer to the TROUBLESHOOTING section.
7. Adjust the output power using the potentiometer on the front panel using the front panel meter.
8. Select the FWD setting, using the “Measure select” push-button.
WARNING: The transmitter can work properly within ± 10 % of the nominal main supply voltage
and is designed to support main supply spikes, although it is preferable to use the main voltage
stabilizers to reduce the risk of damage.
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4. FREQUENCY SETTING
1. Lower the output power to its minimum level.
2. If the exciter is equipped with the “EXTERNAL FREQUENCY SETTING” (/C option) the
selection of the frequency is immediate using the external contraves.
The weights of the contrave numbers are as follows;
Fig. 4.1 - CONTRAVES WEIGHT
3. If the transmitter has internal frequency setting, to change frequency open the cover of the
modulator board (N° 8 Fig. 1.3) and use the internal dip-switches (see Chapter 7). The weight of
the internal dip-switches is indicated on the next page. To find the correct dip-switches
configuration corresponding to the needed FM channel, please refer to the following example with
98 MHz frequency.
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a - Put every dip-switches of the modulator board on the ON position
b - Select the OFF position for the dip-switch with the maximum weight, lower than or equal to the
frequency wanted (for example f 0 = 98 MHz put on OFF the 81.92 MHz switch)
c - Select 98 - 81.92=16.08 MHz, the minimum weight, lower than or equal to 16.08 MHz, is 10.24
MHz; now put off the corresponding switch.
d - Select 16.08 - 10.24 = 5.84 MHz, the minimum weight, lower than or equal to 5.84 MHz, is 5.12
MHz, now put off the corresponding switch .
e - Select 5.84 - 5.12 = 0.72 MHz, the minimum weight, lower than or equal to 0.72 MHz, is 0.64
MHz, then put off the corresponding switch.
f - Select 0.72 - 0.64 = 0.08 MHz, there is a weight equal to 0.08 MHz, so turn OFF the
corresponding switch to complete the setting.
The final configuration is:
4 - Adjust the desired output power using the front panel potentiometer.
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5. ADJUSTMENTS AND MEASURES
AF INPUTS DEVIATION ADJUSTMENT
For the Left and Right input signals (/S option) use the corresponding XLR female connectors on
the rear panel. - see also appendix A for information about the connection
The input impedence is 600 W.
The transmitter accepts, adjusting input trimmers, input signal levels from -6 dBm to +10 dBm for a
75 kHz peak deviation.
For Mono input signal (PM300 without /S option) the input female XLR connector have the same
input levels than the stereo amplifier.
For MPX input signal (PM300 without /S option) the BNC input connector, labeled MPX IN (10
kW input impedance), accepts 0 dBm MPX signal level.
For SCA signals (>53 kHz) use BNC input connectors (1 kW input impedence): the input level for a
correct deviation of the main carrier (about 1.25 kHz peak) is 2.2 Vpp. To adjust the peak deviation
of the main carrier use the front panel potentiometer: look at the front panel meter and select the
DEV measurment by means of the selection button.
The front panel allows to monitoring all the main functions and protections of the transmitter.
Þ “LOCK” led: It shows the correct lock of the frequency synthesis circuit (PLL) on the modulator
board.
Þ “STEREO” led: It shows the use of the internal stereo generator board (/S option present). This
led is related to the switch labeled “STEREO/MONO” which allows selection of the type of signal
to be modulated.
The mono signal is obtained by a semi-sum of the left and the right signals. If the internal stereo
generator board is not present, the switch mentioned above and the corresponding LED are not used.
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Þ “REMOTE” led: It indicates if the operation of the transmitter can be remote controlled. This
selection is made using the switch “REMOTE/MANUAL”. This switch and the relative led will be
unused if the transmitter is not equipped with the remote optional control board.
Þ “ON” led: It shows the ON/OFF state of the transmitter, thus the presence of main power supply.
Þ “OVERHEAT” led: It indicates that the over temperature protection is enable.
This protection does not need a RESET because it restores the normal working conditions
automatically, when the temperature goes back to normal values.
Þ “VSWR” led: It shows that the VSWR protection is active. This intelligent protection is
characterized by an automatic reset delayed by about 2-3 seconds to avoid the risk of accidental
intervention. This auto-reset tries to resume to normal operation only 3-4 times, then turns the
transmitter off definitively (after the intervention of the VSWR protection, use the “RESET” pushbutton.
Þ “PWR LIM” led: It shown that the output forward power becomes greater than the preset value
(normally 300W).
MEASURES
On the front panel there is a leds meter bar which allows the measurement of the most important
parameters of the transmitter. The push-button labeled “MEASURE SELECT” allows to select the
measurement required.
Each measure selected light on one of the leds below the bar.
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6. POWER SUPPLY SECTION
6.1 GENERAL DESCRIPTION
PM 300 transmitter power supply is composed of the following elements:
n°1 switching power supply module (PBIT 2180) to power supply the mosfet amplifier and the
equipment power supply board.
n°1 equipment power supply board (Fig. 6.8) capable of ±12 VDC (6A max) and +24 VDC (10A
max) to power supply the Protection and control boards, meter stage, Sintel ’96 modulator board,
AMP30 Driver stage and all optional boards present .
WARNING: before substituting a broken switching module it is necessary to disconnect its output
and to set the output voltage, without any load, at the right value (22.5v ± 2%) before reconnecting
the switching module output to the other circuits and boards in order to avoid overvoltage roblems.
The switching-mode power supply provides:
1. the efficiency is 80% higher hence provides a considerable reduction of the internal heating, thus
simplifying the cooling system;
2. a lower thermal and mechanical stress for associated components, such as transformer, diodes,
rectifier bridges is inflicted;
3. the power supply voltages at the output of the switching regulators are constant even in case
of wide main fluctuations (± 15 %).
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Fig. 6.1 - SWITCHING POWER SUPPLY MODULE ELECTRICAL SCHEMATIC “A”
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Fig. 6.2 - SWITCHING POWER SUPPLY MODULE ELECTRICAL SCHEMATIC “B”
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Fig. 6.3 - SWITCHING POWER SUPPLY MODULE COMPONENT LAYOUT
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6.2 SWITCHING POWER SUPPLY MODULE PART LIST
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Fig. 6.4 – EQUIP. PWR SUPP. BOARD GENERAL ELECTRICAL SCHEMATIC
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Fig. 6.5 - EQUIP. PWR SUPP. BOARD +24 V STAGE ELECTRICAL SCHEMATIC
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Fig. 6.6 - EQUIP. PWR SUPP. BOARD-12V STAGE ELECTRICAL SCHEMATIC
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Fig. 6.7 - EQUIP. PWR SUPP. BOARD +12V STAGE ELECTRICAL SCHEMATIC
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 6.8 - EQUIP. PWR SUPP. BOARD COMPONENT LAYOUT (DB 0206_090)
30 /108
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
6.3 EQUIP. PWR SUPP. BOARD PARTS LIST (DB 0206_090)
ITEM
QUANTITY
REFERENCE
PART
____________________________________________________________________________________________
CN2,CN3,CN4,CN5,CN6,CN0
AK700 2VIE MORS2
C37,C1
1nF NP0 CC2010
C2,C5,C12,C27,C28,C30,
100nF POL CP2010
C32,C33
C7,C3
1000uF 63V RHOE CEL75D16
C6,C31,C34
100uF 25V CE1025
C9
2n2F MKP 400V C40M
C10,C11
2200uF 50V RHOE CEL75D18
C20
220uF 35V CE2045
C21A,C25
100nF CER CP2010
10
C21,C24
220nF POL CP2010
11
C23
4n7F POL CP2010
12
C22
1n5F POL CP2010
13
C26
330uF 25V CE2045
14
C35
1uF POL CP2020
15
C36
100pF NPO CC2010
16
D1
18V 1W DZ4015
17
D2
BYV27 DBYV
18
D3
MUR3020 DO247V
19
D4
SB360 TRAD D6020
20
D5
1N5819 TRAD D4010
21
FA1
FAST2 TRAD FAST2V
22
F1
MURATA TRAD MURATA
23
JP3
STRIP10F STRIP10M
24
JP5
STRIP5F STRIP5M
25
L1
130uH TORO12A LT70150
26
L2
260uH TORO2A LT3595
27
L3
100uH TORO2A LT2865
28
L4
10uH TRAD L5015
29
L6
VK200 TRAD VK200H
30
Q1
IRFP150N DO247V
31
Q2
BD140 SOT32 +VITEeDADOM3+ALETTA
32
RS1
0.01Ω SHUNT SH1
33
RV1
22KΩ TRAD T1RV
34
RV2
1KΩ TRAD T1RV
35
R0
680Ω 4W R8020
36
R1
100KΩ 1/4W R4010
37
R2
5.6Ω 1% R3010
38
R3
22Ω 1/8W R3010
39
R4
10KΩ 1/8W R3010
40
R5
56Ω 1/2W R5015
41
R6
2K7Ω 1/4W R5015
42
R7
47Ω 1/8W R3010
43
R8
10Ω 1/8W R3010
44
R10
37K4Ω 1% R4010
45
R11
9K09Ω 1% R4010
46
R12
4K7Ω 1/4W R4010
47
R20
0.47Ω 2W R7020
48
R21
100Ω 1/4W R4010
49
R22
270Ω 1/4W R4010
50
R23
10Ω 1/2W R5015
51
R24
1K2Ω 1/4W R4010
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
ITEM
QUANTITY
REFERENCE
PART
____________________________________________________________________________________________
52
53
54
55
56
57
32 /108
R25
SC1
TA1
U1
U2
DB 0201_070
15KΩ 1/4W R4010
47V D10 V3015
150522 TA TA1
L4971 TRAD IC3008
UA78S40 TRAD IC3010
PRINTED BOARD
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 6.9 - DB 0201_070 PRINTED BOARD ELECTRICAL SCHEMATIC
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 6.10 - DB 0201_070 PRINTED BOARD COMPONENT LAYOUT
34 /108
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
6.4 DB 0201_070 PRINTED BOARD PARTS LIST
ITEM
QUANTITY
REFERENCE
PART
_______________________________________________________________________
C1
10nF X7R 0805
11
C2,C3,C4,C8,C9,C10,C17,
100nF X7R 1206
C19,C24,C28,C29
C6,C13,C15,C23,C26,C27
1nF X7R 0805
C7,R11,C14,C18,C22,C25
N.C. X7R 0805
C11
220pF C0G 1206
C12
4n7F X7R 1206
C16
100nF X7R 1206
C31,C21
1nF X7R 1206
C33
2n2F X7R 1206
10
D5,D1
LL4148 MMELF DIODO
11
D2,D6
3V3 MMELF ZENER
12
D3,D4
BAT85 MMELF DIODO
13
D7,D9,D10
BAV103 MMELF DIODO
14
D8
18V MMELF ZENER
15
JP3
STRIP10M MASCHIO 90°
16
JP5
STRIP5M MASCHIO 90°
17
P1
10KΩ 10GRO PANNELLO
18
Q1
BC847 SMD SOT23
19
Q2
BC857 SMD SOT23
20
R2,R25,R27
56K2Ω SMD1% 0805
21
R3
470KΩ SMD 0805
22
R21,R5
10KΩ SMD 0805
23
R6,R12,R20
0Ω SMD 0805
24
R7
10KΩ SMD 0805
25
R8,R29,R30,R33
10K0Ω SMD1% 0805
26
R9
100Ω SMD 0805
27
R10,R35
1KΩ SMD 0805
28
R13
5K6Ω SMD1% 0805
29
R14
3K32Ω SMD1% 0805
30
R15
8K2Ω SMD 0805
31
R16,R23
150KΩ SMD1% 0805
31
R17
20K0Ω SMD1% 0805
32
R18,R22,R26
10K0Ω SMD1% 1206
33
R19
4K7Ω SMD 0805
34
R28
33K0Ω SMD1% 1206
35
R31
2K4Ω SMD1% 0805
36
R32
120KΩ SMD1% 0805
37
R42,R34
4K7Ω SMD 1206
38
R36,R37,R41
330Ω SMD 1206
39
R43
47KΩ SMD 1206
40
R44,R45
100Ω SMD 1206
41
U1
LM324 SMD SO14
42
U2
UC3842 SMD SO8
43
U3
TL431 SOT23/TO92
44
U4
L6384 SMD SO8
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
7. MODULATION STAGE (Sintel 96)
7.1 GENERAL DESCRIPTION
The new modulator board SINTEL ’96 allows a high quality direct carrier modulation accepting a
composite stereo (MPX) or a mono input signal with up to 3 SCA subcarriers (for example RDS,
ARI, ...).
The mono input signal is filtered by a 7th order elliptic filter with a very flat response (20Hz to
15kHz with ± 0.25 dB) and an optimum out of band attenuation (>50 dB for frequencies higher
than 19 kHz), then the signal is amplified (or attenuated) and passed to the VCO oscillator for the
FM carrier modulation. The VCO is controlled by a digital PLL circuit with a high stability quartz
reference to obtain a very stable synthetized oscillation: the frequency setting is customizeable using
on board dip-switches (the minimum step size is 10 kHz).
The composite stereo signal and the SCA subcarriers are just amplified or attenuated by the correct
modulation depth adjustment before going through the VCO stage: the stereo performances of
SINTEL ’96 are excellent, (stereo separation >60 dB from 20Hz to 15 kHz, SNR > 80 dB).
Before the VCO stage, an adjustable and bypassable deviation limiter prevents the FM carrier from
an excessive modulation depth and adjacent channel interference according to all the international
standards (CCIR, FCC). Furthermore, an automatic locking circuit enables the output modulated
signal of SINTEL ’96 only when the internal PLL is locked properly, in order to avoid unwanted
emissions.
36 /108
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 7.1 - “SINTEL 96” MODULATION BOARD GENERAL ELECTRICAL SCHEMATIC
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37 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 7.2 - PLL STAGE ELECTRICAL SCHEMATIC
38 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 7.3 - VCO STAGE ELECTRICAL SCHEMATIC
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 7.4 - LF 1 STAGE ELECTRICAL SCHEMATIC
40 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 7.5 - LF 2 STAGE ELECTRICAL SCHEMATIC
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 7.6 - FILTER STAGE ELECTRICAL SCHEMATIC
42 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 7.7 - “SINTEL 96” MODULATION COMPONENT LAYOUT (DB 9604-010)
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
7.2 “SINTEL 96” MODULATOR PARTS LIST
ITEM
QUANTITY
REFERENCE
PART
__________________________________________________________________
CN1
SMB SMB DA STAMPATO
CN3,CN2
AMP4
18
C1,C16,C18,C25,C26,C36,
100n POLY
C37,C84,C94,C95,C100,
C101,C108,C111,C114,C116,C118,C119
C2
15p
C3
10-60p
C4,C5,C8,C12,C21
10n POLY
C6,C7
4n7 POLY
C9,C14,C102
1u POLY
C10,C19,C59,C61,C63,C85,
10n CER
C86,C120,C121
10
C13
1u POLY
11
14
C15,C17,C23,C33,C39,C40,
1n CER
C41,C42,C43,C44,C45,C46,C47,C48
12
C22,C31,C79,C99,C115,
10u ELETT.25V
C117
13
C27,C28,C29,C82,C83
1u ELETT.25V
14
C30,C66,C67,C70,C105,
10p CER
C112,C122
15
C32
47u elettrol. tantalio
16
C34
33p CER
17
C35
22p CER
18
C51,C49
47p CER
19
C50,C52,C56,C58,C60,C62,
100p CER
C109,C110
20
C53,C71
330n poly
21
C57
4p7 cer
22
C64,C65
100u 25V
23
C69,C91,C92
100n cer
24
C72,C73,C75,C77,C80,C96,
3n3 CER
C97,C98
25
C87
220p CER
26
C88,C89,C90
4n7
27
C126,C93
100p
28
C103
100n CP1
29
C106
100n
30
C107
68p CER
31
C113
1p CER
32
C125
22p
33
C127
1u
34
C128
10n multistrato
35
D3,D12,D13,D15,D16,D17,
1N4148
D18
36
D4,D6,D9,D10
5V1 ZENER
37
D5
LED
38
D8,D7
BB809
39
JP6
JUMPER JUMPER X2
40
JP8,JP7
JUMPER
41
J1
CON20
44 /108
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
ITEM
QUANTITY
REFERENCE
PART
_______________________________________________________________________________
42
J4,J3
CON14
43
L1
INDUCTOR
44
L2,L15
100n INDUTT ASSIALE
45
L3
10R 1/2W 1/2 W
46
L9
10uH
47
L10
10uH R1
48
L11,L12,L14
10uH INDUTT.
49
L13
10uH INDUTT.
50
Q2,Q3
BC557
51
Q4,Q5,Q6,Q7,Q8
BFY90
52
Q9
BC307
53
Q10
BC237
54
R?
22K 1/8W
55
R1,R2,R3,R4
27K4 1% RES 1/8W
56
R5
48K7 1% RES 1/8W
57
R7,R6
27K RES 1/8W
58
R8
22K RES 1/8W
59
R9
48K7 1%
60
R10,R24,R73
1M RES 1/8W
61
R11
50K Trimmer multigiri
62
R12,R34,R38,R42,R108
47K RES 1/8W
63
R15
2.2K RES 1/8W
64
14
R16,R18,R22,R56,R74,R103,
10K RES 1/8W
R106,R130,R131,R132,R133,
R134,R135,R136
65
R17
560 RES 1/8W
66
R20,R29
1K5 RES 1/8W
67
R21,R31,R35,R124
470 RES 1/8W
68
R23
6.8K RES 1/8W
69
14
R25,R37,R39,R41,R54,R58,
1K RES 1/8W
R60,R75,R79,R80,R111,R118,R119,R121
70
R26,R69
5k6 RES 1/8W
71
R27
330 RES 1/8W
72
R28
15k RES 1/8W
73
R30,R36,R40,R62
33k RES 1/8W
74
R33,R32
100 RES 1/8W
75
R43
680R 1/8W
76
R45,R44
31K6 1% 1/4W
77
R47,R46
10K 1% 1/4W
78
R48,R49
169K 1% 1/4W
79
R138,R50
5K6
80
R51,R137
1M
81
R52
3K3 RES 1/8W
82
R53,R57,R71,R72
4K7 RES 1/8W
83
R55,R59,R61
180K RES 1/8W
84
R66,R110
4K7 TRIM MONOGIRO PICC.
85
R109,R68
560R RES 1/8W
86
R77
10K TRIMMER MULTIGIRI
87
R78
20K trim
88
R81
560R 1% 1/4W
89
R82
301k RES_1/4W_1%
90
R83
3k57 RES_1/4W_1%
91
R84
536R RES_1/4W_1%
92
R85,R91,R97,R115,R116,R117
3k01 RES_1/4W_1%
93
R87
3k3 RES_1/8W
94
R88,R94
2k trim multi
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
ITEM
QUANTITY
REFERENCE
PART
_____________________________________________________________________________
95
R89
4k64 RES_1/4W_1%
96
R90
2k74 RES_1/4W_1%
97
R93,R98
2K2 RES_1/8W
98
R95
4k02 RES_1/4W_1%
99
R96
1k91 RES_1/4W_1%
100
R100
2k RV64W
101
R101
2k61 RES_1/4W_1%
102
R102
301k 1/4W 1%
103
R104
2K2 RES 1/8W
104
R105
2K2
105
R107
10K TRIM MONOGIRO PICC.
106
R112
68K RES 1/8W
107
R113
12K1
108
R114
9K53 RES 1/8W
109
R120
10R RES 1/8W
110
R122
68 RES 1/8W
111
R123
10 RES 1/8W
112
R125
47 RES 1/8W
113
R126
220R RES 1/8W
114
R128
100R RES 1/8W
115
R129
330R RES 1/8W
116
SW2,SW1
DIP SW 8
117
TP1,TP4,TP5,TP6,TP7,TP8,
TP
TP10
118
U1
MC145152
119
U2,U19
TL082
120
U3
78L05
121
U4
MB501L
122
U6
78L08
123
U10,U16,U17,U18
TL084
124
U15
74HC14
125
Y1
2.56MHz
46 /108
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
8. AMP30 DRIVER STAGE
8.1 GENERAL DESCRIPTION
The pre amplifier/driver stage is realized by the new 30W MOSFET amplifier board
(DB 0110_010A). This board is basically composed of four amplification WIDE BAND stages.
The first stage uses a BFQ19 transistor to amplify the input level. The second and the third
transistors are 2N4427. The last amplification stage uses a BLF245 MOSFET to obtain an output
RF power 30 W maximum.
The P3 trimmer (see Fig. 8.2) in the AMP30 board allows to adjust the mosfet bias current.
.An external panel trimmer and the P2 trimmer in the AMP30 board allows to adjust the
output power.
The AMP30 board is equipped with an initial 5-6 seconds delay to avoid accidental out of
band emissions in the initial PLL locking period.
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 8.1 - AMP30 PRE AMPLIFIER ELECTRICAL SCHEMATIC
48 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 8.2 - AMP30 PRE AMPLIFIER COMPONENT LAYOUT (DB 0110_010A)
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
8.2 AMP30 PRE AMPLIFIER PARTS LIST
ITEM
QUANTITY REFERENCE
PART
_____________________________________________________________________________
C1
47uF
35V
p=3.5mm f=8mm
C2,C7,C9,C35,C59
100uF
25V
p=2.5mm f=6,5mm
C3,C4,C5,C23,C24,C39,C51 10nF
X7R
1206
C6,C53,C65
10nF
COG
1210
C11,C12,C36,C37
100pF
COG
1206
C16
47pF
TEKELEC 1210
C20,C32,C40,C42
10uF
25V
p=2.5mm f=5,5mm
10
C30,C21
100nF
X7R
1206
11
C27,C28,C29,C33
1nF
X7R
1206
12
C31,C34,C52
1nF
COG
1206
13
C38
10pF
TEKELEC 1210
14
C41
330pF
COG
1206
15
C54,C44
1nF
TEKELEC 1210
16
C45
33pF
TEKELEC 1210
17
C50
100uF
35V
p=3.5mm f=8mm
18
C55
82pF
TEKELEC 1210
19
C57
3p3F
TEKELEC 1210
20
DZ1
5V1
ZENER
SOD80
21
D2,D1
LL4148
DIODO
MMELF
26
L1,L2,L5,L9,L11,L12
VK200
TRAD
VK200SMD
27
L3
15nH
SMD
1210
28
L6,L7,L10
CU x BOBINE IN ARIA
33
P2,P3
5KΩ
SMD
1GRV
5x5mm
34
Q1
BFQ19
SMD
SOT89
35
Q2
BDX53
TRAD
TO220
36
Q3
2N3866 / 2N4427
TO205
37
Q4
2N4427
TRAD
TO205
38
Q5
BLF245
SMD
SOT123A
39
Q6
BC857
SMD
SOT23
40
R1,RX,R0
0Ω
1/4W
R4010
41
R2
100Ω
SMD
1206
42
R14,R3
1K5Ω
SMD
1206
43
R4
100Ω
2W
P=16mm f=4mm
44
R5
22KΩ
SMD
1206
45
R6,R8,R42
1KΩ
SMD
1206
46
R7
56Ω
SMD
1206
47
R7A
47Ω
SMD
1206
48
R10,R12,R15,R16
300Ω
SMD
1206
49
R11
18Ω
SMD
1206
50
R13
150Ω
SMD
1206
51
R17
10Ω
SMD
1206
52
R20,R21,R24
10KΩ
SMD
1206
53
R22
220KΩ
SMD
1206
54
R23
100KΩ
SMD
1206
55
R43A,R43
220Ω
SMD
1206
56
R44
2K7Ω
SMD
1206
57
R59
220Ω
4W
P=20mm f=5mm
58
U1
LM7815
TRAD
TO220
59
U2
NE555
SMD
SO08
50 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
9. RF AMPLIFIER STAGE
9.1 AMP300 AMPLIFIER BOARD
The AMP300 amplifier shown in Fig. 9.2 is implemented with MOS transistors Philips
BLF278 or equivalent.
The BLF278 offer a better performance than a BJT implementation.
The BLF278 technical data (for class C operation) is:
- operation in the 87.5 - 108 MHz frequency range
- 45 - 50 Vds Voltage between drain and source
- 80% efficiency (typical)
- 300 W Output Power with 22 dB gain (typical)
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 9.1 - AMP300 AMPLIFIER ELECTRICAL SCHEMATIC
52 /108
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 9.2 - AMP300 AMPLIFIER COMPONENT LAYOUT (DB 9812_001)
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
9.2 AMP300 AMPLIFIER PARTS LIST
ITEM
QUANTITY
REFERENCE
PART
_____________________________________________________________________________
CS1
DB971202
CS2
DB9812-001
CS3
DB9704-015
C0
10pF CER
C1
150pF CER
C2
56pF CER
C8,C3
100nF 200V
C4
10nF 200V
C5,C6,C7
1nF HQ300V
10
C9
100uF 63V
11
C10
5,6pF HQ
12
L1
6 TURNS 17cm 0.8RS
13
L2
FERR2TUBE
14
Q1
BLF278
15
R5
150 kR 1206
16
R6,R7,R8,R9
22R4W
17
TP1,TP2
CPFXCS
18
TR1
2TUBEOTTx2cm+TEFLONRSx20cm
54 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
9.3 LOW PASS FILTER AND DIRECTIONAL COUPLER
Fig. 9.3 - L. P. FILTER AND DIR. COUP. ELECTRICAL SCHEMATIC
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55 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 9.4 - L. P. FILTER AND DIR. COUP. COMPONENT LAYOUT (DB 9611-005)
9.4 L. P. FILTER AND DIR. COUP. PARTS LIST
ITEM QUANTITY REFERENCE
PART
________________________________________________________
C1,C4,C5,C9
15p
C2,C3
18p
C12
10p
C7
33p
C6,C8,C10,C11
1n
D3
1N4148
D1
BAR10
L1,L2,L6
2 TURNS WITH COPPER WIRE
L3,L8
5 TURNS WITH COPPER WIRE
10
L4,L7,L9
3 TURNS WITH COPPER WIRE
11
L5,L10
4 TURNS WITH COPPER WIRE
12
R2,R3
100R
13
R4,R5
1K
14
R6
1K
56 /108
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
1.5mm
1.5mm
1.5mm
1.5mm
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
10. PROTECTION STAGE
DB 9702-004 and DB 9703-011 boards are connected together and located just behind the front
panel. They realize the intelligent protection, control and monitoring of PM 300 transmitter.
On the J1 input/output connector (see Fig. 10.6) of the DB 9702-004 there are:
1) “FWD” and “REFL” signals coming from the directional coupler.
These are DC voltages that correspond to output forward and reflected power levels.
2) The “V+” signal. It is a 45 VDC voltage that power supply the protection board.
3) The “Measure INSTR” signal represents the selected measure that is visualized on the front
panel meter.
4) “VPA” signals are the DC power supply voltages (@ 45V in normal operation) of the 300W
power module.
5) “IPA” signals are the DC power supply current (@ 9A in normal operation) of the 300W power
module.
6) The “TEMP” signal is connected to a temperature sensor (bimetallic lamina type) mounted on
the heat sink. This sensor works like a contact normally closed to ground, that opens when the heat
sink temperature becomes higher than 70°C.It closes again when the temperature decreases below
45°C.
7) “GATE” signal is a control voltages connected to the MOSFET gate on the 300W-power
amplifier. The gate voltage control allows to realize protection and AGC controls.
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The equipment has three protections:
1) VSWR protection: When the output reflected power becomes greater than a preset value
(normally 30W), the output power reduces to maintain the reflected power below the preset value.
For changing the preset value, adjust the R40 trimmer (Fig. 10.6).
When the protection is active the front panel “VSWR” led lights on.
2) PWR LIMIT protection: When the output forward power becomes greater than a preset value
(normally 300W), e.g. because of a high driving power, the amplifier gain reduces to maintain a
stable output power level (+/-2%). For changing the preset value, adjust the R47 trimmer (Fig. 10.6).
When the protection is active the front panel “PWR LIM” led lights on.
3) Temperature protection: When the heat sink temperature becomes higher than 70°C the output
power decreases to a preset value (normally 40W). For changing the preset output value for
temperature protection, adjust the R121 trimmer (Fig. 10.6). When the protection is active the front
panel “OVERHEAT” led lights on.
WARNING: Any modification or variation must be made only with DB Elettronica
authorization, otherwise voiding the warranty.
58 /108
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 10.1 - PROTECTION /CONTROL STAGE N°1 GENERAL SCHEMATIC
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 10.2 - UNBALANCING PROTECTION STAGE
60 /108
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Fig. 10.3 - FWD PROTECTION STAGE
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Fig. 10.4 - TEMPERATURE PROTECTION STAGE
62 /108
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Fig. 10.5 - POWER LIMITING STAGE
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
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Fig. 10.6 - PROTECTION /CONTROL STAGE N°1 COMPONENT LAYOUT (DB 9702_004)
66 /108
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
10.1 PROTECTION /CONTROL STAGE N°1 PARTS LIST
ITEM QUANTITY
REFERENCE
PART
_______________________________________________________________________
67
10
14
10
11
12
13
14
20
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
C1,C2,C3,C4,C5,C6,C7,C8,
C9,C10,C11,C12,C13,C14,
C15,C16,C17,C18,C25,C26,
C28,C29,C30,C31,C32,C34,
C35,C36,C70,C71,C72,C74,
C75,C76,C80,C84,C88,C102,
C105,C106,C107,C108,C109,
C114,C115,C116,C117,C118,
C119,C120,C121,C123,C124,
C125,C126,C127,C128,C129,
C130,C131,C132,C133,C134,
C135,C136,C137,C138
C19,C20,C21,C22,C37,C38,
C39,C40,C68,C69
C27,C33,C73
C122
D5,D6,D7,D8,D9,D10,D11,
D13,D14,D21,D23,D24,D25,
D26
FIS1,FIS2
JP1
JP2,JP3
J1
J2
J3,J4,J5,J6,J7,J8,J9
Q2,Q3
R5,R6,R7,R22
R8,R9,R10,R11,R12,R13,
R14,R15,R16,R17,R18,R19,
R21,R24,R26,R119,R151,
R152,R153,R154
R20,R27,R28,R35,R43,R116,
R124
R23,R40,R47,R121
R25,R127
R34,R36,R42,R44
R87,R37
R38,R46,R130
R39
R41,R48,R117
R45,R128,R129
R53
R118,R159
R120
R122
R123
R125
R126
U1,U2,U3
U9
U10
1n CER
100n POLY
1u POLY
1n POLY
1N4148
FIS
JUMPERx2
JUMPERx2
JUMPERx3
JUMPERx3
CON24 CON AMP 24
CON20 CON FLAT 20
PINSTRIP Fx2 PINSTRIP Fx2
BC237
33K RES 1/8W
10K RES 1/8W
4K7 RES 1/8W
5K TRIM MULTIG.
1K RES 1/8W
10K RES 1/4W 1%
3K3 RES 1/4W
1M
RES 1/8W
5K62 RES 1/4W 1%
1K
RES 1/4W 1%
1K
RES 1/4W
20K RES 1/4W 1%
2K2 RES 1/4W
8K66 RES 1/4W 1%
3K3 RES 1/8W
22K RES 1/8W
15K RES 1/8W
47K RES 1/8W
TL084
79L05
TL082
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67 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 10.7 - PROTECTION /CONTROL STAGE N°2 GENERAL SCHEMATIC
68 /108
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Fig. 10.8 - PROTECTION STATUS STAGE
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69 /108
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Fig. 10.9 - POWER SUPPLY STAGE
70 /108
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Fig. 10.10 - MEASURES ADJ. STAGE
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71 /108
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Fig. 10.11 - LED INDICATIONS STAGE
72 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 10.12 - PROTECTION /CONTROL STAGE N°2 COMPONENT LAYOUT (DB 9703_011)
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73 /108
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
10.2 PROTECTION /CONTROL STAGE N°2 PARTS LIST
ITEM
QUANTITY
REFERENCE
PART
______________________________________________________________________
10
10
11
12
13
14
15
16
17
18
19
20
21
22
23
10
24
25
26
27
28
29
30
31
32
33
34
35
36
74 /108
C54,C132
10u
Elett.50V
C55,C92,C93,C94,C98,C110,
1n
CER
C111,C112,C113,C131
C56,C57,C64,C128,C129,
100u
Elett.25V
C133,C134
C58
22u
Elett.63V
C59,C60,C62,C130,C135
10n
POLY
C61,C127
100p
CER
C65,C66,C82,C83,C103,
100n
POLY
C104
C77,C81,C85,C89
10u
Elett.25V
C95,C96,C97,C99
1u
POLY
D15,D17,D18,D19,D20,D22
LED
LED3MM
D16,D27
1N5819
Diodo
FIS1,FIS2,FIS3,FIS4
FIS
J3,J4,J5
PINSTRIP Mx2 PINSTRIP Mx2
L1,L9
100u
INDUTT
L3,L4,L5,L6,L7,L8
150u
INDUTT
Q1,Q4,Q5,Q6,Q7
BC237
R29,R50,R52,R133
1M
RES 1/8W
R30,R49,R51,R132,R140,
1K
RES 1/8W
R144,R145,R150
R88,R89,R90
1K5
RES 1/4W
R91
100R
RES 4W
R92
1K54
RES 1/4W 1%
R93
16K9
RES 1/4W 1%
R95,R96,R97,R98,R99,R100,
1K
TRIM RO
R135,R136,R137,R138
R102,R141,R142,R147,R148,
22K
RES 1/8W
R155,R156,R157,R158
R103,R111
1K
RES 1/4W
R104,R105,R106,R109
150K
RES 1/8W
R107,R108
15K
RES 1/8W
R110,R112,R113,R131
4K7
RES 1/8W
R114,R115,R134
1K2
RES 1/4W
R139,R143,R146,R149
47K
RES 1/8W
R160
1K
RES 1/4W 1%
R161
8K66
RES 1/4W 1%
R162,R163,R164,R165
1R
RES 1/4W
U11,U4
TL084
U7,U12
UA78S40
U8,U13
LT1054
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
11. METER STAGE
11.1 GENERAL DESCRIPTION
The meter stage is built using two boards:
The ST62T25 microprocessor board DB 9903_040
The display board DB 9903_050 is composed of forty LED bargraph display.
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DB
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Fig. 11.1 - MICROPROCESSOR STAGE ELECTRICAL SCHEMATIC (DB 9903_040)
76 /108
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Fig. 11.2 - MICROPROCESSOR BOARD COMPONENT LAYOUT (DB 9903_040)
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77 /108
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
11.2 MICROPROCESSOR BOARD PARTLIST
ITEM QUANTITY
REFERENCE
PART
__________________________________________________________________________
10
11
12
13
14
15
16
17
18
19
20
21
78 /108
C17,C18,C19,C20,C25
C21,C23,C24
C22
DL7,DL8,DL9
D1,D2,D3
JP1,JP2
JP10,JP11
JP21,JP20
J1,J2,J3
J4
J6
J7
R9,R10,R12,R13,R16,R17,R18
P1
R11,R14,R19,R20,R21,R22
P2,P3,P4,P5
Q2,Q1
R15
S1,S2
U8
U9
100Nf mul.
1nF cer.
1uF 50V ele.
LED 3mm.
1N4148
STRIP2M
STRIP7M
STRIP5M
CNM20V
CNM14V
AMP4
CNM10V
1K
1K
10K
10K
BC547
680R
C&K
TL082
74HC32
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 11.3 - DISPLAY STAGE ELECTRICAL SCHEMATIC (DB 9903_050)
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79 /108
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 11.4 - DISPLAY BOARD COMPONENT LAYOUT (DB 9903_050)
80 /108
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
11.3 DISPLAY BOARD PARTS LIST
ITEM
QUANTITY
REFERENCE
PART
1nF cer.
10
11
11
12
13
14
15
16
17
18
19
20
21
22
23
C1,C8,C9,C10,C11,C12,C13
C14,C15
C2
C3
C4,C16
C5,C6
C7
DL1,DL2,DL3,DL4,DL5,DL6
JP30,JP31
L1,L2,L3
Q3,Q4,Q5,Q6,Q7,Q8
RR1,RR2,RR3,RR4,RR5,RR6,
RR7,RR8,RR9,RR10,RR11
R0,R1
R2
R3
R4,R5,R8
R6,R7
SW1
U1
U2
U3
U4,U5,U6,U7
U10
Y1
1uF 50V ele.
10uF 50v ele.
100nF
mul.
22pF cer.
1u pol.
LED 3mm.
STRIP12M
10uH
BC517
4X1K rete res.
47R 1W
4M7
47K
4K7
1K
PULSMOZ
ST6225
ULN2803
4028
LED_BAR
78L05
4MHz QUARZO
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81 /108
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12. IN-AUDIO BOARD
Fig. 12.1 - IN-AUDIO BOARD ELECTRICAL SCHEMATIC
82 /108
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Fig. 12.2 - IN-AUDIO BOARD COMPONENT LAYOUT (DB 9909_010)
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
12.1 IN-AUDIO BOARD PARTS LIST
ITEM QUANTITY REFERENCE
PART
________________________________________________________
C1,C3,C5,C7
C2,C4,C6
JP1,JP2,JP3,JP4,JP5
J1
J2,J3
J4,J10,J20
J5,J6,J7,J8,J11,J12,J13,J14
100pF CER.
4n7F POL.
STRIP3M
CNM20V
CNM14V
CNM10V
BNC90CS
10
11
12
13
L1,L2,L3,L4
PR,PL
RL,RR
R1
TMPX
TSC1,TSC2,TSC3
10uH
XLRF90CS
5K 10GROP
470R 1/4W
10K 10GROP
1K 10GROP
84 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
12.2 IN-AUDIO BOARD JUMPERS SETTING
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13. STEREO ENCODER BOARD (Option)
13.1 CHANNELS PRE- EMPHASIS SETTING
RIGHT CHANNEL PRE-EMPHASIS
(see Fig. 13.3 and Fig. 13.10)
To change the pre-emphasis, you need to set (or change position of) the JP3, JP4 jumpers on the
STEREO encoder board.
To disable preemph you have to remove both jumpers; to get a 50 us preemph, you have to insert
only JP3; if you want a 75 us preemph both JP3 and JP4 must be inserted.
LEFT CHANNEL PRE-EMPHASIS
(see Fig. 13.3 and Fig. 13.10)
To change the pre-emphasis, you need to set (or change position of) the JP5, JP6 jumpers on the
STEREO encoder board.
To disable preemph you have to remove both jumpers; to get a 50 us preemph, you have to insert
only JP6; if you want a 75 us preemph both JP5 and JP6 must be inserted.
86 /108
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DB
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Fig. 13.1 - STEREO ENCODER GENERAL SCHEMATIC
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
87 /108
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Fig. 13.2 - L/R PEAK DETECTOR STAGE ELECTRICAL SCHEMATIC
88 /108
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89 /108
DB
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Fig. 13.3 - INPUT STAGE ELECTRICAL SCHEMATIC
90 /108
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DB
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Fig. 13.4 - RIGHT FILTER STAGE ELECTRICAL SCHEMATIC
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
91 /108
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Fig. 13.5 - LEFT FILTER STAGE ELECTRICAL SCHEMATIC
92 /108
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Fig. 13.6 - OSCILLATOR STAGE ELECTRICAL SCHEMATIC
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93 /108
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Fig. 13.7 - 19 kHz STAGE ELECTRICAL SCHEMATIC
94 /108
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Fig. 13.8 - 38 kHz STAGE ELECTRICAL SCHEMATIC
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95 /108
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Fig. 13.9 - OUTPUT STAGE ELECTRICAL SCHEMATIC
96 /108
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Fig. 13.10 - STEREO ENCODER COMPONENT LAYOUT (DB 9506-001)
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
13.2 STEREO ENCODER PARTS LIST
ITEM
QUANTITY
REFERENCE
PART
_______________________________________________________________
C64,C65,C135
220n poly
C1
56p cer np0
38
C2,C3,C4,C10,C13,C14,C15,
100n poly
C16,C17,C22,C23,C24,C25,
C26,C27,C28,C29,C36,C37,
C51,C52,C53,C54,C55,C56,
C57,C58,C59,C66,C69,C81,
C82,C83,C84,C85,C86,C89,
C90
C8
33p cer np0
C9
10-60p orange
C11,C44
10p cer np0
C12
18p cer np0
C20,C21
330p cer
C38
3p3 cer np0
10
C39
5p6 cer np0
11
C40
27p cer np0
12
C41
47p cer np0
13
17
C42,C107,C108,C109,C110,
3n3 polistirene
C111,C112,C113,C114,C117,
C118,C119,C120,C121,C122,
C123,C126
14
C43,C61
82p cer np0
15
C45,C49
470p polistirene
16
C46
330p polistirene
17
C47,C63
68p cer np0
18
C48
15p cer np0
19
C62,C50
120p cer np0
20
C60
3-18p red
21
12
C67,C68,C79,C80,C91,C92,
10u tant 25V
C95,C96,C115,C116,C124,
C125
22
C70,C71,C77,C78
100p
23
C72,C73,C75,C76
10p cer
24
C74,C102,C106
100p cer
25
C87,C88,C97,C98
330n poly
26
C99,C100,C101,C103,C104,
4n7 polistirene
C105
27
C127
100p cer np0
28
C128
680p cer np0
29
C129
10p
30
C130,C134
3n3
31
C132,C131
47u TANTALIO
32
C133
1n poly
33
D1,D2,D3,D4
1N4148
34
JP2,JP1
jumper
98 /108
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ELETTRONICA TELECOMUNICAZIONI S.p.A.
ITEM
QUANTITY
REFERENCE
PART
_________________________________________________________________
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
JP6,JP3
JP5,JP4
J2,J1
J3,J4
L5
L1,L2,L3,L4
RL1
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R11,R68,R75
R12
R13,R80,R82,R83,R102,
R104,R106
R14
R15
R16
R17,R30,R55,R76
R18
R19,R26
R20,R25
R21,R24
R22,R23
R27,R63,R64,R67,R69,R70,
R74
R28,R29
R31
R32
R33
R34
R35,R36
R37
R39,R38
R40,R53,R54,R58,R59
R41
R42
R43
R44
R45
R46
R47
R48,R49
R50,R51
jumper ON/OFF
jumper 50/75us
CON14
CON20
10uH ind. assiale
10uH
G6H-2-100 OMRON 22Z3K3 12V
1k 1/8W
1M 1/8W
11k 1/4W 1%
11k5 1/4W 1%
12k4 1/4W 1%
14k3 1/4W 1%
17k4 1/4W 1%
23k2 1/4W 1%
37k4 1/4W 1%
113k 1/4W 1%
9k53 1/4W 1%
8k66 1/4W 1%
2k trim multi
511R 1/4W 1%
5OOR trim multi
487R 1/4W 1%
4k7 1/8W
10k 1/4W
324k 1/4W 1%
115k 1/4W 1%
75k 1/4W 1%
64k9 1/4W 1%
12k1 1/4W 1%
2k15 1/4W 1%
6k81 1/4W 1%
13k 1/4W 1%
10k5 1/4W 1%
909R 1/4W 1%
1k47 1/4W 1%
5k trim multi
10k 1/4W 1%
31k6 1/4W 1%
50k trim multi
20k 1/4W 1%
825R 1/4W 1%
1k5 1/4W
20k trim multi
15k 1/4W
0R 1/4W
10k 1/8W
100k 1/8W
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
ITEM
QUANTITY
REFERENCE
PART
__________________________________________________________________
83
84
85
86
87
88
89
12
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
100 /108
R52,R60
R56
R57
R61,R62
R65,R66,R71,R77
R73,R72
R78,R81,R93,R94,R95,R98,
R100,R103,R105,R115,R116,
R118
R79,R101
R84,R85,R107,R108
R86,R91,R99,R113
R87,R109
R88,R110
R89,R111
R90,R112
R92,R114
R96,R117
R97,R119
R122
R123
R124
R125
R126
R127
U1
U2
U3
U4,U5,U12,U13
U6,U16,U23,U24,U25,U26
U7A,U7,U18B,U27
U8
U9,U10,U11
U14,U15
U19,U22
U20
U21
Y1
680R 1/4W
10k trim multi
2k2 1/8W
560R 1/4W
169k 1/4W 1%
22k 1/8 W
3k01 1/4W 1%
3k3 1/4W
2k2 1/4W
301k 1/4W 1%
3k57 1/4W 1%
4k64 1/4W 1%
4k02 1/4W 1%
2k61 1/4W 1%
1k91 1/4W 1%
2k74 1/4W 1%
536R 1/4W 1%
0R
5k6
100R 1/4 W
100R 1/4W
4K7
10k 1/4 W 1%
4001
4024
4013
4035
MC33079
NE5532
4066
4053
TL084
TL082
7805
7905
2.432MHz
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
14. CONTRAVES BOARD (Option)
14.1 GENERAL DESCRIPTION
On the synthesized board the dip-switches are changed with a 20 pin connector, so that it is
possible connect with a flat type cable this circuit (that manage PLL) to a microprocessor.
The frequency change is fast, because it is only necessary put directly the frequency using the
contraves on the front panel.
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 14.1 - CONTRAVES BOARD ELECTRICAL DIAGRAM
102 /108
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 14.2 - CONTRAVES BOARD COMPONENT LAYOUT (DB 9308-020)
14.2 CONTRAVES BOARDS PARTS LIST
ITEM QUANTITY REFERENCE
PART
______________________________________________________
CN1
CONN 20
CN2
CONN 10
C2,C1
10p cer
C3,C4,C6
10u
C5,C7,C8
100n pol
21
D1 - D22
1N4148
D21
LED d3
JP1,JP2,JP3,JP4,JP5, jumper
JP6,JP7,JP8,JP9,JP10
R1,R2,R3,R4
47K
10
R5
1k
11
R6
2M2
12
R8,R7
10k
13
S1,S2,S3,S4,S5
CONTRAVES
14
U1
78L05
15
U2
MC68HC705C8P
16
X1
2-4 MHz
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
15. TROUBLESHOOTING
In the following table there is a list of the most frequent malfunctions, the corresponding symptoms
and their possible solutions for the PM300 transmitter.
CAUSE
AC main absent
SYMPTOM
ACTION SUGGESTED
-PWR led OFF when
Check the presence of the
transmitter
connection to the electric line
switched ON
and the integrity of the power
cord.
Check the fuse (N°1 Fig. 1.2).
If the fuse is burnt check that
the voltage of the electric line
is the same (115 or 230Vac) as
the one selected by the rear
panel switch (N° 2 Fig. 1.2)
and then replace the fuse.
VSWR or TEMPERATURE
- No output power
If on the front panel the
protection intervention or
-VSWR led ON or TEMP led
VSWR led is light on, check
defective lock of the PLL circuit ON or LOCK led OFF.
the integrity of the output load
on modulator.
(antenna or dummy load) and
the corresponding cables, then,
perform a RESET using the
push-button (N° 12 Fig. 1.2).
If the led TEMP on the front
panel is light on, control the
room temperature (should be <
45°C). If under 45°C, allow
about 15 minutes for the
proper cooling of the
equipment; the protection will
turn off automatically.
If the problem persists, please
104 /108
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
contact DB’s Technical
Service.
If on the front panel the LOCK
led is light off, control the DC
voltage that is on the audio
and SCA inputs (the DC
voltage should be lower than
1 V otherwise there could be
PLL locking problems):
if it is correct, please open the
transmitter cover and the
modulator box cover (N° 8
Fig. 1.3 and check the supply
voltages ±12Vdc
presence on the modulator
board. If the voltages are not
correct, please check the
internal connectors and the
relative cables. If the problem
persists contact DB
Elettronica.
Output power adjustment not
- Very low output power
correct
Adjust the output power level
using the front panel trimmer
(Fig. 1.1).
Excessive or low deviation
- Received audio: very low or
- Adjust input audio levels and
badly distorted
front panel potentiometer (Fig.
1.1) following indications in
Chapter 5.
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
16. APPENDIX A
16.1 XLR AUDIO CONNECTORS PINOUTS
Connection procedure to connect the audio signal cables to the XLR female connectors for a
balanced or unbalanced signal.
XLR FEMALE
XLR CONNECTOR PIN
106 /108
BALANCED SIGNAL
ground
" +"
"-"
UNBALANCED SIGNAL
ground
not connected
signal
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
17. APPENDIX B
17.1 MOSFET REPLACEMENT
1. Disconnect the supply voltage from the output board (faston connection).
2. Unscrew the damaged MOSFET and the output matching board.
3. Unsolder the MOSFET.
4. Clean the input and output boards to prevent short-circuits before replacing the MOSFET.
5. Locate properly the white teflon sheets between the output circuit and the heat sink: affix the
circuit using the two screws.
6. Put on the thermically conductive compound between the MOSFET case and the heat sink.
7. Fix the MOSFET to the heat sink (screws must be strongly fixed) and solder all the four pins of
the MOSFET: careful attention must be paid to the output board soldering since an
excessive quantity of tin can cause a short circuit between different board layers. Reconnect
also the 2 GND interconnections, indicated on Fig. 17.1, and check the right soldering of the
input transformer and gate resistor.
8. Verify that the supply voltage is 45V (if it is not, there is a problem in the switching power
supply boards). Reconnect the supply voltage to the 300W module (faston connection), placing
an ammeter in series (minimum full scale deflection 10A).
9. Control the output power level (it should be 300W) and the absence of spurious emissions (to
check it, use a spectrum analyzer and an output RF monitor sufficiently attenuated). Pay
attention to the ammeter: the MOSFET must not drain more than 9A.
10. In case the replaced MOSFET doesn’t reach the nominal output power or in case of spurious
emissions you need to improve the input matching of the MOSFET: to do this compress or
expand manually the input circuit coil (see Fig. 17.1) to maximize the output power.
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DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
Fig. 17.1 - MOSFET REPLACEMENT
108 /108
PM 300 - FM Broadcasting Transmitter - USER’S MANUAL
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Title                           : PM300  R2.0    24/06/2004
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