PA1000 FM Broadcast Amplifier

Transcription

1 PA000 FM Broadcast Amplifier Technical Manual v.0 No part of this manual may be re-produced in any form without prior written permission from BW Broadcast. The information and specifications contained in this document is subject to change at any time without notice. Copyright 00 BW Broadcast

2 CONTENTS. Introduction. FM Power Amplifier. Warranty. Safety. Front And Rear Connections. Control And Monitor LCD. Installation And Setup. R.F. Power Setup. R.F. Fail Alarm. RS Control & Monitoring. Windows remote control application. Terminal control of the amplifier.. Specifications. Circuit Description. LCD control board. Control and alarm port. Power amplifier board. Block Diagram. Internal Wiring / Case Overview. Schematics. LCD control board. Remote control and alarm board. Power amplifier board. PSU interface. Bus bar. Fan Connector board. D to IDC Board. PA Controller Board. Double Pallet. Output combiner. Parts List. LCD control board parts list. Remote and alarm board parts list. Power amplifier board parts list. PSU interface. Bus bar. Fan Connector board. D to IDC board. Controller Board. Double Pallet. Output combiner BW Broadcast technical manual Page

3 . PA000 FM POWER AMPLIFIER Introduction The BW Broadcast PA000 is a high specification FM broadcast power amplifier. Its broadband no-tune design allows.-0 MHz operation and digital PWM techniques provide an easily adjustable and accurate automatic level controlled R.F. output of the MOS-FET power amplifier stage. RF power, temperature and other parameters are shown on the LCD graphics display. This display offers a very easy method of amplifier parameter monitoring and a new level of ease for setup and installation, with metering accuracy normally only found on expensive test equipment. Local and remote personal computer control and metering are achievable via RS interface and there's an alarm I/O as well. The lightweight universal mains input design ensures a high reliability efficient design compatabile with any mains system in the world. BW Broadcast technical manual Page

4 . WARRANTY Introduction BW Broadcast warrants the mechanical and electronic components of this product to be free of defects in material and workmanship for a period of two () years from the original date of purchase, in accordance with the warranty regulations described below. If the product shows any defects within the specified warranty period that are not due to normal wear and tear and/or improper handling by the user, BW Broadcast shall, at its sole discretion, either repair or replace the product. If the unit has a manufacturers fault within twenty eight () days then BW Broadcast will pay the freight at their discretion. If the warranty claim proves to be justified, the product will be returned to the user freight prepaid. Warranty claims other than those indicated above are expressly excluded. Return authorisation number To obtain warranty service, the buyer (or his authorized dealer) must call BW Broadcast during normal business hours BEFORE returning the product. All inquiries must be accompanied by a description of the problem. BW Broadcast will then issue a return authorization number. Subsequently, the product must be returned in its original shipping carton, together with the return authorization number to the address indicated by BW Broadcast. Shipments without freight prepaid will not be accepted. Warranty regulations Warranty services will be furnished only if the product is accompanied by a copy of the original retail dealer s invoice. Any product deemed eligible for repair or replacement by BW Broadcast under the terms of this warranty will be repaired or replaced within 0 days of receipt of the product at BW Broadcast. If the product needs to be modified or adapted in order to comply with applicable technical or safety standards on a national or local level, in any country which is not the country for which the product was originally developed and manufactured, this modification/adaptation shall not be considered a defect in materials or workmanship. The warranty does not cover any such modification/adaptation, irrespective of whether it was carried out properly or not. Under the terms of this warranty, BW Broadcast shall not be held responsible for any cost resulting from such a modification/adaptation. Free inspections and maintenance/repair work are expressly excluded from this warranty, in particular, if caused by improper handling of the product by the user. This also applies to defects caused by normal wear and tear, in particular, of faders, potentiometers, keys/buttons and similar parts. Damages/defects caused by the following conditions are not covered by this warranty: Misuse, neglect or failure to operate the unit in compliance with the instructions given in BW Broadcast user or service manuals. Connection or operation of the unit in any way that does not comply with the technical or safety regulations applicable in the country where the product is used. Damages/defects caused by force majeure or any other condition that is beyond the control of BW Broadcast. Any repair or opening of the unit carried out by unauthorized personnel (user included) will void the warranty. If an inspection of the product by BW Broadcast shows that the defect in question is not covered by the warranty, the inspection costs are payable by the customer. Products which do not meet the terms of this warranty will be repaired exclusively at the buyer s expense. BW Broadcast will inform the buyer of any such circumstance. If the buyer fails to submit a written repair order within weeks after notification, BW Broadcast will return the unit C.O.D. with a separate invoice for freight and packing. Such costs will also be invoiced separately when the buyer has sent in a written repair order. Warranty transferability This warranty is extended exclusively to the original buyer (customer of retail dealer) and is not transferable to anyone who may subsequently purchase this product. No other person (retail dealer, etc.) shall be entitled to give any warranty promise on behalf of BW Broadcast. Claims for damages Failure of BW Broadcast to provide proper warranty service shall not entitle the buyer to claim (consequential) damages. In no event shall the liability of BW Broadcast exceed the invoiced value of the product. Other warranty rights and national law This warranty does not exclude or limit the buyer s statutory rights provided by national law, in particular, any such rights against the seller that arise from a legally effective purchase contract. The warranty regulations mentioned herein are applicable unless they constitute an infringement of national warranty law. BW Broadcast Technical Manual Page

5 . SAFETY Introduction MAINS VOLTAGE This equipment operates from an AC power source of between 90 and volts. There are hazardous voltages present internally. PLEASE OBSERVE CAUTION WITH THE COVER REMOVED. SWITCHED MODE POWER SUPPLY HAZARD Please note that the power supply units in this equipment is of the switched mode variety and have lethal voltages present internally. The switched mode supplies are universal input fully approved type. They are non serviceable modules and should be fully replaced should they fail. FUSES Only use fuses with the specified voltage and current ratings as stated on the back panel. Failure to do so may increase the risk of equipment failure, shock and fire hazard. R.F. The N type R.F. power output socket contains R.F. voltages which may burn or present a shock. Please make sure that the equipment is connected to an adequately rated load or antenna system while in operation. TOXIC HAZARD This equipment includes R.F. components that may contain Beryllium oxide which is a highly toxic substance that could be hazardous to health if inhaled or ingested. Care should be taken when replacing or discarding such devices. Seek expert advice from the manufacturer should you physically damage a device that contains Berillyium Oxide. The main R.F. output power transistor contains Beryllium oxide. OTHER SAFETY CONSIDERATIONS Do not operate this equipment in the presence of flammable gases, fumes or liquids Do not expose this equipment to rain or water. CE CONFORMANCE This device complies with the requirements of the 99//EC Radio and Telecommunications Terminal Equipment (R&TTE). The equipment will meet or exceed the following standards: EN 0:99 (Safety Requirements for Radio Transmitting Equipment), EN 0 9- (ERM/EMC for Radio Equipment, Part Specific Conditions for FM Transmitters), EN 0 0- ERM (Transmitting Equipment for FM Radio Broadcasting service) This amplifier together when used with an FM exciter may form an FM transmitter system intended for FM audio broadcasting utilising operating frequencies not harmonised in the intended countries of use. The user must obtain a license before using the product in the intended country of use. Ensure respective country licensing requirements are complied with. Limitations of use can apply in respect of operating frequency, transmitter power and/or channel spacing. WEEE COMPLIANCE BW Broadcast Ltd is registered with Northern Compliance PCS number WEE/ UPPR/SCH and has been issued with WEE/FA0RX as its unique producer ID by the appropriate environment agency. BW Broadcast Ltd full comply with it explicit responsibilities, subject to WEEE Collections Policy outlined in their General Terms and conditions of Sale, when it sells Electrical and Electronic Equipment (EEE) to BB customers in the UK and EU. This appliance has been designed and manufactured with high quality materials and components that can be recycled and reused. Electronic appliances are liable to contain parts that are necessary in order for the system to work properly but which can become a health and environmental hazard if they are not handled and disposed of in the proper way. Consequently, please do not throw your inoperative appliance with the household waste. Having purchased this appliance it is your responsibility to dispose of this equipment appropriately. BW Broadcast technical manual Page

6 . FRONT AND REAR PANELS Introduction 9 0 FAULT VSWR TEMP,. RF Input. I/O + Alarms. RS. R.F. output. Power socket. Chassis ground post. RF monitor output -0dBc (not suitable for harmonic measurements). VSWR and temperature fault LEDs 9. Maximum forward power adjust 0. LCD display. Up / Down frequency buttons FAULT VSWR TEMP 9 I/O - Alarms D-type connector pinout: Pin +V DC 00mA Pin RF Mute Pin RF failure alarm (TTL) Pin PLL failure alarm (TTL) Pin MOD failure alarm (TTL) Pin GND Pin RF failure alarm (OC) Pin PLL failure alarm (OC) Pin 9 MOD failure alarm (OC) BW Broadcast technical manual Page

7 . CONTROL AND MONITOR LCD Introduction The front panel LCD graphics display has seven screens (shown below). These allow monitoring of the amplifier s R.F., audio and other parameters and the adjustment of the amplifier s power. You can move through the screens by pressing the NEXT button, which will display them in the following order. Main parameter screen. This shows together the three most important amplifier parameters. R.F. output power, PA temperature and DC voltage. R.F. Power The forward and reverse R.F. powers are displayed. The up/down buttons will allow power control if internally allowed. The maximum output power is governed by the maximum power set adjustment (see R.F. pwr control section). Power supply Power amplifier voltage is shown together with the amplifiers secondary supply that feeds the exciter section. The power amplifier voltage will vary depending on set output power and the presence of any fault conditions which also cut the voltage back and with it the R.F. output. P.A. temperature This display indicates the temperature of the heatsink that the R.F. power transistor is bolted to. The normal operating temperature range is 0-0 degrees at full R.F. power output. BW Broadcast technical manual Page

8 . R.F. POWER SETUP Installation and setup The R.F. power output from the amplifier can be controlled by an analogue potentiometer (POT) or from the front panel LCD screen or a combination of both. When the power is to be controlled from the front panel the max power set POT takes on a new role of setting the maximum power of the amplifier. If you want the LCD screen to have full power range control of the amplifier you will need to ensure that the max power set control is at maximum power. Otherwise your control range may be limited. This feature enables you to limit the amplifiers maximum power to a fixed level but to still allow the LCD screen to provide adjustment of the R.F. power down from that maximum power set point. This can be desirable in amplifier hire situations where you wish to govern the maximum output to a fixed level but to allow the customer (hirer of the amplifier) to run the power of the amplifier at a lower level if they so decide. The maximum power set is positioned to the lower left of the LCD screen on some models, other models may not have the hole in the front panel and you will need to remove the lid of the amplifier to access the adjustment which will be in the same position but on the other side of the PCB. You will need a small tweaker style flat-head screwdriver to adjust the pot. This control is quite delicate so try to not be too heavy handed in it s adjustment. 0 Please note that the VSWR and temperature protection circuitry will turn back the R.F. power if a fault condition exists. Make sure that you have a good VSWR (low reverse power reading) before setting the R.F. power as the removal of a fault condition may cause the R.F. power to increase. BW Broadcast technical manual Page

9 . R.F. FAIL ALARM Installation and setup The amplifier has an alarm that can alert the broadcaster if RF power fails. The alarm when set is available on the back panel 9-pin D-type as an open collector (OC) and a TTL level contact. The alarm induced active open collector can pull down any external signals and the TTL output will provide a Volt indication. The open collector can sink 00 ma MAX with an absolute maximum switched voltage of volts. The alarm is also visible if any RS monitoring (through the Windows Remote Control application or terminal software) is employed. The RS interface provides the ability to reset the alarms either through Windows Remote Control application or terminal software. More info is found in the following pages of the manual. BW Broadcast can also customise the alarm / fault software to meet the requirements of major broadcasters and networks or supply N+ solutions. More information on this and other custom features can be obtained from our technical department. For the alarm to function correctly the amplifier must be left on the default menu screen. This is the screen that displays R.F. power, temperature and PA voltage. To ensure that the alarm system functions correctly the amplifier will return to the default menu screen if the LCD is left on another menu screen for more than minutes. The R.F. power alarm will be set if the R.F. power falls below a threshold level during normal operation. This threshold is set below the normal operating lowest wattage available from the amplifier. If you require a different setting for the alarm, contact our tech dept. The alarm will only be set if the fault condition exists for sixty seconds or more. You will need to reset the amplifier to clear the alarm/s or you can do it via the RS connection. BW Broadcast technical manual Page 9

10 . RS CONTROL AND MONITORING Installation and setup The PA range of FM power amplifiers can be monitored or controlled from a personal computer either locally or remotely. The Transmitters can chat either by a windows application or via a standard serial terminal program. The windows application is the more versatile option and is to be preferred but the ability to use a terminal program can prove useful in the absence of the windows application or a computer that runs windows.. Windows remote control application The latest version of Windows remote control application can be downloaded from: Installation After downloading just click on the.msi file to run the set up program. The set up will place icons in both the Windows start menu and on your desktop. Simply run the program by clicking on icon from either location. Running the application When started the application will resemble the picture to the right. The application can connect to any COM port currently available on your computer that is running the application. Connect a serial cable between the RS connector on the rear of the transmitter and one of your computers COM ports. If you are using a codec or other STL device then you may be able to connect that device in line to act as part of the serial link. Selected the COM port you want to use and then click the Connect button. Remote Control Applictiona startup screen Remote Control Application If the application is able to connect to the transmitter then you will be presented with a screen similar to the one above. Once connected you should be able to monitor all the parameters of the transmitter as well as being able to mute the R.F., change the R.F. power and reset an alarm flag.. Terminal control of the transmitter Installation Please see the instructions for your terminal software package to find out how to connect to a remote serial device. The transmitter is internally set to communicate at 900 bps, no parity with stop bit and hardware flow control. This is commonly known as 900 N. If your using Windows then you can use the pre-bundled terminal program Hyper-terminal. This is located in the Programs -> Accessories -> Communications folder accessible BW Broadcast technical manual Page 0

11 from the Start menu. Select direct to COM port x where x is the com port that the transmitter is connected to. You will be presented with a dialog box like the one shown to the right. Select 900,, none, with hardware flow control and then click OK. Installation and setup If you are using another terminal program then you may need to consult the documentation for that software, but it should be pretty much straight forward. Operation The transmitter will respond to certain key presses and each one has a certain function. See the list below for details of what key to press for each function. The most important key press is the Enter key. This will need to be pushed as soon as you connect to the transmitter so you can get the transmitter to refresh your terminal window with the transmitters status and parameters. The transmitter won t respond to any of the other key presses until it detects the Enter key is pressed. Once the Enter key is pressed the transmitter will listen out for other key presses for 0 seconds. This Initial Enter key validation and time window is a safety feature to prevent the transmitter from detecting an erroneous key press such as R.F. power up and causing a service affecting problem. After performing a function you may need to press the Enter key to see a response to your function. For example, If you pressed ' for R.F. power up you would not see the effect of the R.F. power change until you refreshed the screen again because the terminal window would still be showing the transmitters R.F. power from the previous Enter (screen refresh) command, prior to you performing the R.F. power up command. Hyper Terminal connection FWD R.F. PWR REV R.F. PWR P.A. VOLTS P.A. TEMP ALARM R.F. FAIL (=alarm, 0=no alarm) Hyper Terminal window In some circumstances you may need to press the refresh screen key several times in order to see what s happening. It does no harm to wait a second or two before asking for a refresh screen or by asking for several refresh screens by pressing the 'Enter key a few times in succession. KEY COMMAND R.F. power up R.F. power down Reset alarm (to 0 / off) o Mute R.F. f Unmute R.F. ENTER Refresh screen BW Broadcast technical manual Page

12 . SPECIFICATIONS RF Output Power Input Power Input connector Output connector Harmonics Spurious Frequency range 00W - 00W -0W BNC /" DIN 0 Ohm better than dbc better than 90 dbc. - 0 MHz OTHER Control system External control/monitor Size Weight Voltage input Current input Power connector Switched mode approvals buttons, x graphics display I/O Alarm D9-type Male; RS D9-Type Female mm x 9mm x mm kg 0-0 VAC A A C9 IEC UL / TUV / CE BW Broadcast technical manual Page

13 . CIRCUIT DESCRIPTION. LCD CONTROL BOARD The LCD control board is the heart of the amplifier. The board contains an eight bit microcontroller, LCD display, a voltage regulator and a dual op-amp together with a few passive components. CON provides a 0 way interface to the power amplifier board and its sensors. Some of the connections of CON are routed around to the power supply modules. CON provides a way interface to the back panel D- type sockets for alarm/rs signals to the main microcontroller. The voltage regulator REG and decoupling capacitors C and C takes the volt auxillary supply from CON and regulate it down to volts for the microcontroller and LCD circuitry. The microcontroller is a 0 pin bit type running at MHz. The microcontroller has several ports that have various functions and connect to external components. PORTA ( bits) is primarily used for the analogue voltage inputs. Bit is the Fwd RF power. Bit, Bit and Bit are not used and bit of PORTA has a control connection to the LCD display. PORTB ( bits) has a few different functions. Bits, and of the port are the alarm signal outputs and are routed off via CON to the D-type on the back of the control/alarm board. Bit's, and are connected to the front panel buttons to allow navigation of the LCD functions. PORTC ( bits) bits 0 and are used to write information to the LCD display. Bit is the pulse width modulator output (PWM) and connects into unity gain DC amplifier op-amp ICA. The voltage generated by the PWM is set by the software in the microcontroller. This PWM level is then fed through potentiometer VR and smoothed by C before being buffered by the aforementioned op-amp. PORTC bits - are not used. Bit s and of PORTC are used by the UART inside the microcontroller. These pins are RXD and TXD for the RS interface. They are routed via CON to the back panel D-type. PORTD's bit's are interfaced to the bit data bus of the LCD display. The data byte on PORTD can be latched into the LCD display by the LCD control bits on PORTC. PORTE ( bits) has the remaining A/D inputs. Bit 0 is the PA volts, Bit is the Rev RF power and bit is for the PA temperature. The microcontrollers software reads all the analogue voltages, converts and displays them where neccessary and outputs alarm signals in the event of a amplifier error. There are various passive components associated with IC. Each A/D port has input current limiting resistors R- and decoupling capacitors C-. X, C and C provide the MHz signal for the clock of the microcontroller. R and R provide pull downs for correct operation of the inter processor communications channel. C provides supply decoupling for the microcontroller and VR sets the contrast of the LCD display. IC is a dual op-amp whose purpose is to control the output power of the amplifier. Side A of the op-amp is configured as a unity gain buffer for the PWM and was described previously. VR provides an adjustable DC level to side B of the op-amp. Side B is configured as a DC amplifier with the gain set by R, R, R9, R0 and R. The larger the DC signal provided by side A and the larger the DC signal at the output of Side B. This DC signal is used to turn down the output of the Power amplifiers power supply and with it the RF power output level. LED and R0 provide a connection from the reverse RF power sensor into the input the non inverting input of side B of the op-amp. LED only allows DC through above a certain level. Any DC above this level will increase the output voltage from the op-amp and the RF power level will decrease. This forms the VSWR protection for the amplifier. LED and LED also provide the same function but with the DC level this time being supplied by the temperature sensor on the PA board. Too high a temperature will cause the DC level to exceed the turn on point of the two diodes and voltage will once again turn up the op-amps voltage and turn down the RF power level which should lower the temperature of the amplifier. The output from side B is fed to the switched mode power supply of the power amplifier via R and CON. R and C provide supply decoupling for the op-amp. C,,,, provide further decoupling and feedback for the power control feedback loop formed around side B of the op-amp. BW Broadcast technical manual Page

14 . CONTROL AND ALARM PORT The control and alarm board is the interface of the amplifier with the outside world. It has two main functions - one is the remote control of the amplifier with a personal computer (via RS). The other is to provide TTL and open collector alarm for RF fail and the ability to mute RF power (i.e. for backup switch-over). CONA is a 9-pin D-type connector for RS connection to the PC. Pins and are transmit and receive connections for the RS interface (IC and associated C-C). IC communicates via pins and on CON with the microcontroller on the LCD control board. TTL signals coming from LCD control board on pins - are routed through R-R to the control/alarm D-type connector CONB on the back of the amplifier. They are also used to drive NPN transistors T-T that provide open collector outputs for these alarm signals. Pin on CONB is used as an input to mute the power amplifier RF output. REG is a V voltage regulator for IC. It is fed by V from the LCD control board (pin on CON). REG supply rails are decoupled with C, C and C. BW Broadcast technical manual Page

15 . POWER AMPLIFIER BOARD PSU interface CON (0 Pin) provides the interface between the plugin power supply and the interface PCB, and supports the main 0V output as well as the V auxiallary power, and all PSU control parameters. LED's D & D are used to indicate AGC_OFF and AC_OK status. The high current inductor L and capacitor C smooth the main output voltage, and the headers J & J set PS_ON and PS_Kill status. Bus bar board The busbar PCB is located onto the side face of the windtunnel and interfaces with the Fan control PCB and D to IDC PCB through sub-minature D-type connectors, fixed in place with several hanks.the main voltage from the PSU arrives at input of REG through the -pin EDGE connector. REG is a switching regulator. The khz output signal from REG is half rectified by D and smoothed out through L, C and C. The resulting DC voltage is used to drive both the rear panel 0mm fans. R which is in the feedback loop of REG, adjusts the maximum voltage to accommodate different fan types and/or calibrate the fan speed. Part of the feedback loop includes a temperature sensor TH (placed on the rear of the bus bar board), making the amount of airflow in the amplifier temperature dependent through the fan speed adjustment. The LED D indicates there is an output voltage present for the fans. The V Auxillary output from the PSU is fed to a boost regulator REG through the -pin edge connector where it is increased to V, half recitifed by D before being fed to the V regulator REG and out to the 0 Pin header J to provide the power to the Combo board. C, and C are used to smooth the V output from REG. Fan Connector Board This PCB provides two independant V fan outputs via the screwless terminal connector CON, and is filtered by the two capacitors C, and C. D to IDC Board The way D-type connector J interfaces with the Way D-type J on the D to IDC PCB. Each pin on the D-type is filtered individually with SMT capacitors C-C, with 0 pins running to the Controller Board and the remaining carrying the 0V line to power the dual Double Pallets. PA Controller board The controller board controls the power output of an output amplifier based on forward VSWR detection, reverse VSWR detection, forward power signal from the LCD board and temperature. All op-amps are supplied with +V from the AUX power supply line, buffered by the capacitors C, C, C and C. Detected reverse VSWR (sniffed of the power amplifier's main RF output line) arrives through CON and input filter C-R to the ICA. The gain of the op-amp is set by R and R. Amplified signal is smoothed by C and C and fed to the OR-ing circuit on the input of ICB. Detected forward VSWR (sniffed of the power amplifier's main RF output line) arrives through CON and input filter C-R to the ICB. The gain of the op-amp is set by R9, R0 and VR. Amplified signal is smoothed by C and fed to the OR-ing circuit on the input of ICB. Forward power control signal comes from the micro controller on the LCD board to the inverting input of ICA through R and C0. A voltage divider R and R sets the voltage reference to the non-inverting input to be half of the AUX power supply rail. The gain of the op-amp is set by R and R. Output signal is fed directly to the ICB. ICB includes an OR-ing circuit on the input and a summer (R-R) to combine the reverse VSWR, forward VSWR and PA control signals together. Output of ICB is then a final control signal that controls the output of the power amplifier by controlling it's power supply voltage. R and VR set the voltage reference to the inverting BW Broadcast technical manual Page

16 input of ICB. A temperature sensor circuit is located close to the main RF transistors. This temperature sensor is mounted into the heatsink and consists of the sensor itself which is located under the board and an op-amp circuit for level adjustment. The op-amp ICA provides a suitable voltage reference while ICB and associated components convert the output signal from the temperature sensor to a level more suitable for the micro controller and protection circuitry on the LCD board. Double pallet The RF signal arrives at the input connector CON. From here the 0 ohm input impedance is distributed to two branches via a bridge consisting of two quarter-length 0 Ohm lines. In each branch a RTF (RTF) impedance matching balun provides an unbalanced to balanced connection to the two gates of gemini packaged FET transistor T (T). Transistors are biased through R9 (R), VR (VR), R, R, R and R. In case of excessive VSWR, a sniffed signal from the output combiner coming through VR will turn the diodes D and D on, and negatively bias transistors T and T off. The drain outputs of T (T) are connected to another balun transformer RFT (RTF) which provides impedance step up as well as proving a DC feed to the transistors drains via a center tapped winding. The DC power applied to the center of balun comes from the main adjustable power supply module which can control the RF power output by having it s output voltage adjusted. C- (C-), FB (FB), R0- (R-), and C (C) provide filtering and RF decoupling to the power feed into the center tap of balun RFT (RTF). Output combiner Two output signals from RTF and RTF are combined together via a bridge consisting of two quarter-length 0 Ohm lines. On each line there is a sniffed signal that drives LEDs D and D in case of excessive VSWR and/or bridge unbalance. Another RF sense circuit consisting of R, R, C, C, D and R produces a negative voltage in the event of excessive VSWR on the combined output which shuts transistors T and T on the double pallet off. The output of the bridge is fed into a low pass output filter. These components reduce the level of any harmonic products generated by the power amplifier. The output of the low pass filter is sniffed by VSWR sensors R, R, C, D, C and R, R, C, D, C which generate forward and reverse RF power measurements for metering and for VSWR fault protection and alarms. BW Broadcast technical manual Page

17 . BLOCK DIAGRAM 0-0 VAC BW Broadcast technical manual Page

18 . WIRING AND INTERNAL OVERVIEW BNC / Socket 9-Pin D-Types IEC Socket (Alarms & RS) FAN FAN Remote/Alarm Interface Board SEMI RIGID COAX Fan Connector PCB RG VSWR OUTPUT COMBINER & FILTER V 00W POWER SUPPLY BusBar WY RIBBON DOUBLE PALLET AMP DOUBLE PALLET AMP Filtered Power PCB PSU Interface board PA Controller PCB 0 WAY RIBBON INPUT SPLITTER LCD Board RF Mon BNC BW Broadcast technical manual Page

19 . LCD CONTROL BOARD BW Broadcast technical manual Page 9

20 . REMOTE CONTROL AND ALARM BOARD 0 9 C+ TIN ROUT TIN ROUT C+ IC TOUT RIN TOUT RIN C- C- VS+ VS- R T R 9 0 VO VI CON CON C C CON A C R B R R T R T R R CONN REG GND C C C C C DRAWN BY: R.K FILENAME: DESIGN TITLE: PA Alarm Port SHEET TITLE: REV: PAGE: / CREATED: 0//99 MODIFIED: 09/0/0 Z:\Products\BW Products\PROTEUS\Current Production 9 9 BW Broadcast technical manual Page 0

21 . PSU Interface 0 9 VRTN VOUT VOUT D C EDGE CONN-DIL VOUT GND AC_OK PS_ON PS_Kill I_SHARE 9 0 P_GOOD V_SB+OUT IC ADRO Vout SENSE+ V_SB+OUT V_SB+OUT IC ADR Vout SENSE- V_SB RETURN V_SB RETURN IC ADR IC DATA V_SB RETURN V_SB RETURN PS_PRESENT IC CLOCK PS_KILL V_SB OUT CTR 0 CTR J J CON D A K R I_SHARE 9 FCI CON K D C A CTR K A I_SHARE V_SB OUT IC ADR0 Vout SENSE+ IC ADR Vout SENSE- IC ADR IC DATA PS_PRESENT IC CLOCK L L V_SB OUT PS_KILL IC ADR0 IC ADR PS_PRESENT IC DATA Vout SENSE+ IC ADR IC CLOCK Vout SENSE- 9 0 J 9 0 J VOUT BW Broadcast technical manual Page

22 . Bus Bar REG VI FeedBack VO LMHVT-ADJ GND ON-OFF C L R R D C C / R R C 0 V VIN K A 0 V VIN T L D +V +V C0 C R0 C9 Vin Switch Comp Feedback LM-ADJ GND C R9 0 V VIN REG R TH C REG +V VI VO V J J V VIN GND J J R 9 C R C C L C C C C PS_KILL C EDGE PSU_CTRL +V PS_KILL PSU_CTRL V R 0 D 0 +V 9 PSU_CTRL BW Broadcast technical manual Page

23 . Fan Connector Board 9 J C J / / / / C BW Broadcast technical manual Page

24 . D to IDC Board J e 9 0 J g C C C C C C C C9 C0 C n o m C C C C C C C C9 C0 C C C C C C j i h g f e d a b c p k r s t q l j b d a c e h j i f x p n v r t l w u q o m y s k u v w x y 0V y x w v u s q p o n m l t r a f d c b h i g TO LCD 0V L BW Broadcast technical manual Page

25 . PA Controller Board AUX V+ C C C C R R C R C IC:A REV REV R C C IC:B FWD R9 FWD /// CON R C /// CON C C VR R0 IC:A R IC:B R C R9 C R VR R PA CTRL R R R PA V+ C IC:A R C C0 R R C R R R9 R0 R C9 R C IC:B TEMP C REV SWR IN FWD SWR IN TEMP V+ AUX AUX C0 C R PAV+ AUX R C9 PACNT TEMP REV PAV+ FWD PACNT 0 9 CON D D D R R R AUX AUX R C R0 R C R PACNT R R DRAWN BY: FILENAME: VR DESIGN TITLE: SHEET TITLE: Controller PCB REV: PAGE: / CREATED: /09/0 MODIFIED: /0/0 BW Broadcast technical manual Page

26 . Double Pallet FB C C R9 VR D C C R T DRAWN BY: R.K FILENAME: RFT RFT C PCB R PCB C C0 D R R C C R T RF OUT RFT RFT PCB C PCB R VR C D D C FB C9 CON /// R R9 R0 R Passive VSWR C R R R C C R RF OUT D D C9 TEMP V- ADJ V+ Temp Signal PWR +0V RF IN RF IN PWR +0V C C R R R0 D VR Passive VSWR D R R R PCB PCB and Assembly Components GND 0 Ohm 0 Ohm BW Broadcast technical manual Page

27 . Output Combiner FWD VSWR DETECTION K D A C C R R9 R D R R R C D A K C A K VSWR PROTECTION REV VSWR DETECTION VSWR Return K A R D R0 D VSWR LED INDICATOR K A RF Output VSWR LED INDICATOR D RF Sense D RF INPUT RF INPUT R / RF Sense RF Sense RF Sense R OUTPUT FILTER R R D A K VSWR PROTECTION VSWR Return K A R D9 D R VSWR LED INDICATOR K A VSWR LED INDICATOR D0 D RF INPUT RF INPUT Combiner Power Resistors RF Sense RF Sense RF Sense BW Broadcast technical manual Page

28 . PARTS LIST. LCD control board Qty Reference Value Description C, C, C, C.uF V Electrolytic Cap C, C 00n.mm Pitch Radial Multilayer Ceramic ( YV ) C, C pf pf Ceramic.mm Pitch 0 C, C, C, C, C9, C0, C, C, C, C 0pF 0pF Ceramic D N N LED mm Mini mm Green LED - L-0GD LED mm Mini mm Red LED - L-0GD R, R, R k / W Metal Film % - CR R, R, R k / W Metal Film % - CR R, R, R0, R 00R / W Metal Film % - CR R 0R / W Metal Film % - CR R9 00k / W Metal Film % - CR R, R, R, R9, R0, R 0R / W Metal Film % - CR R, R 90R / W Metal Film % - CR R 0k / W Metal Film % - CR R k / W Metal Film % - CR R, R R / W Metal Film % - CR R K / W Metal Film % - CR VR 00R Bourns 9 W /in VR 00R Bourns Minipot VR 00k Minipot Spectrol M Reg 0 0CV A VOLTAGE REGULATOR IC 0 Pin 0 Pin PICF-0P (NOT FITTED) IC CA0EZ CA0 Op Amp 0 IC TBA NOT FITTED SW- 9.mm 9mm Tactile Switch X MHz MHz Crystal Connector 0-Way Header Strip (0-Way) LCD Screen LCD Blue LCD Display IC 0-Pin 0 Pin IC Socket IC,IC -Pin -Pin IC Socket Panel Buttons n/a Molded Cap for Switch (NOT FITTED) Con 0-Way 0 Way Boxed Header Con -Way Way Boxed Header. Remote and alarm board Qty Reference Value Description R-R K / Watt Carbon Film - Tolerance +- % R,R 0R / Watt Metal Film Resistor- Tolerance % C-C, C 00n YV Radial Multilayer Ceramic.mm pitch - YV Dielectric C,C 00uF Radial Electrolytic - mm Dia,.mm Pitch, Tolerance +- 0% IC STCN STCN RS TRANSCIEVER T, T, T BC (C) C- TO9 0V NPN GP TRANS REG L0 +V Voltage regulator L0 CON Way Dual Female Dual Double Height D-Type PCB-Mount Connector CON R/A BNC Right Angled BNC PCB-Mount Connectors CON MCX MCX PCB Mount Socket CON way Straight IDC Header CON pin Pin Dil IC socket BW Broadcast technical manual Page

29 . PSU Interface Qty Reference Value Description J Way Way Straight PCB D Plug J 0 Way 0 Way Straight Boxed Header. Bus Bar board Qty Reference Value Description R,R R W Resistor R?? 0.W Metal Film Resistor R,R K 0.W Metal Film Resistor R K 0.W Metal Film Resistor R,R,R9 K 0.W Metal Film Resistor R0 K 0.W Metal Film Resistor C 00uF Electrolytic capacitor mm 0deg Low ESR C,C,C0,C,C,C,C 0uF Electrolytic capacitor mm 0deg Low ESR C nf Ceramic Plate.mm Pitch C 0nF Polycarbonate.mm Pitch C,C,C9,C,C 00nF Ceramic YV Capacitor.mm Pitch C,C 00nF Ceramic YV Capacitor mm Pitch D,D UF0F UF0F Diode D mm LED mm Green LED Reg LMHVT- ADJ Reg LM-ADJ Voltage Reg Reg LM Voltage Reg Voltage Reg (High Voltage) L 0uH 0uH Inductor L 00uH DVE SLR0 J 9 Way 9 Way Straight PCB D Socket J Way Way Straight PCB D Socket J 0 Way 0 Pin IDC straight PCB Male EDGE (J) Way Edge Way Edge PCB Mount + PCB Card Fingers PCB Black Oxide PCB Board (Black). Fan connector board Qty Reference Value Description C,C 00nF Ceramic disc capacitor.mm Pitch J 9Way IDC 9 Way Straight PCB D Plug J DEG Way, Screwless degree, Terminal Block BW Broadcast technical manual Page 9

30 . D to IDC board Qty Reference Value Description R K /W Metal film resistor C 0UF (Not Fitted) V 0DEG Low Impedance Electrolytic C 00pF Ceramic disc capacitor.mm Pitch D V.V Zener 00mW D,D Green LED mm Green LED L uh IHLP 00 Inductor,uH,A,.mohm L uh (Not Fitted) IHLP 00 Inductor,uH,A,.mohm J way Way SIL Header Strip J Way Way SIL Header Strip. Controller board Qty Reference Value Description R k 0.0% Resistor R k 00 % Resistor R,R,R R 00 % Resistor R,R k 00 % Resistor R,R,R,R,R,R,R9,R0 0k 00 % Resistor R k 00 % Resistor R,R M 00 % Resistor R0,R 00k 00 % Resistor R,R k 00 % Resistor R,R NOTUSED 00 % Resistor R0 k 00 % Resistor R-R,R-R NOTUSED 00 % Resistor R9 0R 00 % Resistor R k 00 % Resistor R k 00 % Resistor R9 k 00 % Resistor VR 0R 0 0 Ohm Link VR 0k 0k 0% mm G SMT Cermet Trimmer VR NOTUSED SMT Cermet Trimmer Resistor C NOTUSED SMT Capacitor (X.mm) C-C,C,C9-C,C-C 00nF 00N 00 0V YV Capacitor C uf 00 SMT Capacitor C,C nf 00 SMT Capacitor C 0uF SMT Capacitor (X.mm) C NOTUSED 00 SMT Capacitor C NOTUSED 00 SMT Capacitor C NOTUSED 00 SMT Capacitor C uf SMT Electrolytic Capacitor C n 00 SMT Capacitor D-D NOTUSED SMT Diode IC-IC CA0EZ DUAL BIMOS Op-Amp CON,CON NOTUSED CON CONN-H0 0 WAY Straight boxed header BW Broadcast technical manual Page 0

31 . Double Pallet Qty Reference Value Description R,R k SMT /W Resistor R,R 00R SMT /W Resistor R,R,R,R R SMT W Resistor R9,R K SMT W Resistor R0-R,R-R R SMT W Resistor R 00R 00W Power Resistor R-R 00R SMT W Resistor VR-VR 0k SMT 0k Variable Resistor C,C pf SMT 00nF Capacitor C,C,C,C 00nF SMT 00nF Capacitor C,C 00uF 00uF V Electrolytic Capacitor C,C nf SMT 00V Capacitor C,C nf Polyester Capacitor C9,C0 p Metal clad capacitor C,C Not fitted SMT 00nF Capacitor C9 00nF SMT Capacitor FB,FB H SMT Ferrite Bead,. x.mm D-D BLU-LED SMT Blue LED D,D Not fitted SMT Blue LED T,T BLF BLF Transistor CON CONN-H MCX Connector PCB,PCB PCB PCB Feedback Inductor PCB PCB RFT,RFT - SemiRigid Coax CCW RFT,RFT PCB PCB Transformer TEMP LMZ. Output Combiner Qty Reference Value Description R,R K K 00 Resistor R,R,R,R 0R 0R 00 Resistor R 0R 0R 00 Resistor R 0R 00 Resistor R,R0,R,R R R 00 Resistor R9,R R R 00 Resistor R R 0R 00 Resistor R 0R R R 00R 00 Resistor R R R Resistor R9 NOT FITTED 00 Resistor C,C N 00 Capacitor C,C pf 00 Capacitor C pf 00 Capacitor D-D,D,D,D9,D BAT BAT Single Schotky Diode SOT- D,D,D0,D LED Green LED PCB PCB Board BW Broadcast technical manual Page

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