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Harris Platinum Z2 CD Manual

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Platinum Z2CD™
FM Transmitter Manual
888-2406-002
Platinum Z2 CD™
FM Transmitter Manual
June 9, 2003
T.M. No. 888-2406-002
Rev. C
© Copyright Harris Corporation 2000, 2001
All rights reserved

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Do you have a question about the Platinum Z2 CD and is the answer not in the manual?

Questions and answers

George Basanio
March 12, 2025

Transmitter not coming up low power light is amber when try to turn on tx

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1 comments:
Mr. Anderson
March 12, 2025

The low power light on the Harris Platinum Z2 CD transmitter is amber because the exciter has detected a fault. The transmitter does not turn on because an exciter AFC fault or Exciter FAULT has been recorded. No action is taken until an exciter low power condition is detected. If this occurs, the controller delays for 10 seconds before switching to another exciter, if available.

This answer is automatically generated

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Summary of Contents for Harris Platinum Z2 CD

  • Page 1 Platinum Z2CD™ FM Transmitter Manual 888-2406-002 Platinum Z2 CD™ FM Transmitter Manual June 9, 2003 T.M. No. 888-2406-002 Rev. C © Copyright Harris Corporation 2000, 2001 All rights reserved...
  • Page 2 TELEX service (650/372-2976). Replaceable Parts Service Replacement parts are available 24 hours a day, seven days a week from the HARRIS Service Parts Department. Telephone 217/222-8200 to contact the service parts department or address correspondence to Service Parts Department, HARRIS CORPORATION, Broadcast Systems Division, P.O.
  • Page 3 MANUAL REVISION HISTORY Platinum Z2 CD™ 888-2406-002 Rev. Date Pages Affected 12-17-01 47926 Title page, added MRH1/MRH2, sections 2 and 4. 06-09-03 Title page, MRH1/MRH2 and page 2-30. 888-2406-002 WARNING: Disconnect primary power prior to servicing.
  • Page 4 888-2406-002 WARNING: Disconnect primary power prior to servicing.
  • Page 5 C001 and is not the actual part number for C001. In the ten digit part numbers, if the last three numbers are 000, the item is a part that Harris has purchased and has not manufactured or modified.
  • Page 6 888-2406-002 WARNING: Disconnect primary power prior to servicing.
  • Page 7 The installation, operation, maintenance and service of this equipment involves risks both to personnel and equipment, and must be performed only by qualified personnel exercising due care. HARRIS CORPORATION shall not be responsible for injury or damage resulting from improper procedures or from the use of improperly trained or inexperienced personnel performing such tasks.
  • Page 8 888-2406-002 WARNING: Disconnect primary power prior to servicing.
  • Page 9 FIRST-AID Personnel engaged in the installation, operation, maintenance or servicing of this equipment are urged to become familiar with first-aid theory and practices. The following information is not intended to be complete first-aid procedures, it is a brief and is only to be used as a reference.
  • Page 10 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 11: Table Of Contents

    Typical remote/extended control and status connec- Harris DIGIT Digital FM Exciter ....1-3 tions ........2-25 Harris SuperCiter Analog Exciter .
  • Page 12 Table of Contents RF Flow Block Diagram Description ... . . 4-1 APC, Automatic Power Control ... . . 4-32 Exciters .
  • Page 13 Table of Contents PA Replacement......5-6 Asterisk and Pound Signs(*, #) ....6-12 Directional Coupler Removal and Replacement .
  • Page 14 Table of Contents PAC#_J#, Cable Fault ..... . . 6-24 Power Supply Controller Faults....6-26 General Power Supply Troubleshooting .

  • Page 15: Introduction/Specifications

    • Section 5: Maintenance/Alignments-Adjustments, lists and explains alignments and adjustments which might be required once the transmitter leaves the Harris Broadcast factory. • Section 6: Troubleshooting, is included as a servicing aid, to be used along with Sections 4 and 5 by qualified service personnel to identify and correct any equip- ment problem which might develop.

  • Page 16: Features/Benefits

    The Z2CD and Z2FM are 2kW versions of the Platinum Z FM transmitter. The Z2CD (Clearly Digital) utilizes the Harris DigitCD, Digital FM exciter, while the Z2FM would designate an analog exciter such as the Harris SuperCiter is being used.

  • Page 17: Harris Digit Digital Fm Exciter

    1.3.1 Harris DIGIT Digital FM Exciter The Harris DIGIT FM exciter is supplied as standard equipment with all Platinum Z transmitters. The DIGIT, with its digital input module, generates the complete stereo FM waveform in the digital domain, using a digital signal processor (DSP) as a stereo generator and composite limiter, and a 32-bit numerically controlled oscillator (NCO) as a digital modulator.

  • Page 18: Rf Combining

    Introduction/Specifications The IPA consists of a standard PA Module with one PA on each side of the heatsink. Only one half of the IPA module is active at a time to provide the required drive to the PA. The transmitter contains sensing, logic and switching circuitry which will automatically switch from a failed IPA to the remaining one.

  • Page 19: Directional Rf Sample Port

    Introduction/Specifications 1.3.7 Directional RF Sample Port Platinum Z FM transmitters provide an RF sample port with 30dB nominal directivity. A directional RF sample provides more accurate performance measurements by supplying a nearly reflection free RF sample source for external monitoring equipment. 1.3.8 Power Supplies The Z2 can be configured with a 3-Phase or Single Phase power supply.
  • Page 20 Introduction/Specifications 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 21: Installation & Initial Turn-On

    The contents of the shipment should be as indicated on the packing list. If the contents are incomplete or if the unit is damaged electrically or mechanically, notify the carrier and HARRIS CORPORATION, Broadcast Systems.

  • Page 22: Air Cooling Requirements

    Installation & Initial Turn-On Air Cooling Requirements Harris transmitters are designed to operate in a free, unobstructed environment with a maximum inlet air temperature of 50°C. This means that the transmitter air system is designed to supply sufficient air at the required static pressure to cool the transmitter only.

  • Page 23: Transmitter Placement

    Installation & Initial Turn-On 2.5.1 Transmitter Placement Set the transmitter in place on a level surface near power and signal cables. Either or both sides of the FM Transmitter may be placed against a wall or other equipment. Complete access is through the front and rear of the transmitter. The floor must be capable of supporting a load of 250 pounds per-square-foot (1221 kg per-square- meter) (refer to Cabinet Outline drawing).

  • Page 24: Exciter Installation

    Installation & Initial Turn-On b. Controller Connections 1. Check the Ribbon cables connected to the back of the controller boards and to the exciter(s). 2. Make sure that all of the boards in the controller are properly seated in the backplane (motherboard) connector. 2.5.3 Exciter Installation The exciter may or may not be removed from the transmitter depending on the...

  • Page 25: 3-Phase Power Supply Installation

    Installation & Initial Turn-On 2.5.4 3-Phase Power Supply Installation The Z2 transmitter can be configured with either a 3-Phase or Single Phase power supply. Operation of the supplies is basically the same with both using the dynamic tap switching for efficiency. However, their physical make-up is different and requires separate installation procedures.
  • Page 26 Installation & Initial Turn-On Figure 2-1 3-Phase Power Supply Top View b. The cable labelled A1P2 (multi-conductor cable with gray connector) plugs into its mating connector on the left wall of the power supply compartment, see Figure 2-1. c. Wires #1, #2, and #3 (orange cables tied up on the left side of the power sup- ply compartment) and two smaller gray wires #40 and *#41 plug into the gray Wago block connector, A17TB1 on the front of the power supply tray (A17 designates a component on the power supply tray).
  • Page 27 Installation & Initial Turn-On To insert the wires into the Wago block, insert a screwdriver into the rectangular slot above the wire hole and then carefully lift up. This will open the contact inside the Wago block and the wire can be inserted. Be very careful not to let the wire ends fray as the con- nectors are very close together and could cause a short.

  • Page 28: Dual Power Supply Option

    Installation & Initial Turn-On 2.5.4.3 Dual Power Supply Option To add redundancy the Z2 can be configured with an optional second power supply. The installation procedure only changes slightly for this configuration. The following lists only the additions to the above procedure. h.

  • Page 29: Single Phase Power Supply Installation

    Installation & Initial Turn-On NOTE: Terminals 1 and 2 are connected inside the Wago block as are terminals 3 and 4 and terminals 5 and 6. This allows for connections to the second supply on the output side of the Wago block. j.
  • Page 30 Installation & Initial Turn-On Figure 2-4 Single Phase Power Supply Top View b. The cable labelled A1P2 (gray and yellow multi-conductor cable with gray connector) plugs into its mating connector on the left wall of the power sup- ply compartment, see Figure 2-4. c.
  • Page 31 Installation & Initial Turn-On e. Wire 80 (large orange cable tied up with the transformers) connects to the feed-thru terminal C3 at the top of the power supply compartment. See Figure 2-5. f. The large orange ground wire #52, coming from the power supply attaches to the ground stud at the top-front edge of the power supply compartment.

  • Page 32: Dual Power Supply Option

    Installation & Initial Turn-On 2.5.5.3 Dual Power Supply Option To add redundancy the Z2 can be configured with an optional second power supply. The installation procedure only changes slightly for this configuration. The following lists only the additions to the above procedure. a.

  • Page 33: Transmitter Ac Connections

    Installation & Initial Turn-On 2.5.6 Transmitter AC Connections The AC input for the transmitter should be low impedance, 50/60 Hz, single or three phase depending on transmitter phase supply with sufficient capacity to supply the transmitter. Refer to the “Z2 Outline Drawing” in the drawing package for current ratings, nominal fuse sizes and wire gauge for the 3 phase delta, 4 wire wye, and single phase input voltage combinations.

  • Page 34: Three Phase Ac Connection

    If applicable, the phase-to-earth 275 volt MOVs in the RV7 through RV13 and RV20 positions may be replaced with 510 volt MOVs (Harris part number 5600042000, quantity 8). For safety reasons, you also must install a 4 pole disconnect device if your neutral line is not connected to earth ground.

  • Page 35: Single Phase Ac Connection

    Installation & Initial Turn-On 2.5.6.3 Single Phase AC Connection The single phase connects to the top of the AC mains contactors K1. The two wires should be connected to the terminals closest to the front of the transmitter. The last terminal (toward the rear) is not connected.

  • Page 36: Low Voltage Power Supply And Blower

    Installation & Initial Turn-On may show up as noise or feedback. Wire and cable shields should normally be connected at both ends to the equipment chassis. A ground strap attachment point is located on the top, right rear, of the cabinet (use four 1/4-20 brass screws with brass washers).

  • Page 37: External And Failsafe Interlock Connections

    Installation & Initial Turn-On 2.5.9 External and Failsafe Interlock Connections The transmitter is shipped with two jumpers installed on TB1, the Remote Control Interface terminal strip: TB1-7 to TB1-6(GND) is for External Interlock and TB1-8 to TB1-10(GND) is for Failsafe. 2.5.9.1 External Interlock Connection To use the External Interlock connection, remove the jumper between terminals TB1-7 to TB1-6(GND), then connect external interlock wires.

  • Page 38: Initial Turn-On

    Installation & Initial Turn-On Initial Turn-on Each transmitter is thoroughly checked out during factory final test but adjustment may be required during installation due to shipping, variations in primary power, antenna systems, or transmission line differences. Any remote or extended control connections should be connected only after the transmitter is checked out and fully operational.
  • Page 39 Installation & Initial Turn-On Step 4: Press the PA VOLTS button on the front panel of the controller. Step 5: Press the LOW power ON button on the front of the controller, but be ready to quickly press the off button if necessary. The PA VOLTS reading on the front panel should be above 40Vdc and the blower should come on at HIGH speed.
  • Page 40 Installation & Initial Turn-On IPA_2 IPA_1 Figure 2-8 PA Compartment Front View Figure 2-9 PA Compartment Rear View 2-20 888-2406-002 WARNING: Disconnect primary power prior to servicing.
  • Page 41 Installation & Initial Turn-On Step 7A: Optimization - The Factory Test Data Sheet contains the serial numbers of each of the PA modules. The data sheet also tells which slot each of the PA modules were connected into during factory testing. While it is Not Critical to operation, the transmitter readings may be closer to the data sheet if the PA modules are placed in the same positions as during factory testing.
  • Page 42 Installation & Initial Turn-On Step 10: Turn the transmitter back ON at LOW power. Verify that the exciter power is the same as the factory test data sheet. NOTE: The fan will run at high speed for 1 minute then will automatically switch to low speed provided there are no faults.

  • Page 43: Remote Control Connections

    Installation & Initial Turn-On Remote Control Connections The Platinum Z2 Transmitter may be operated by remote control by connecting a remote control system. If the transmitter is to be remotely controlled, it is important to initiate thorough routine inspection and maintenance procedures at the transmitter location.

  • Page 44: Remote/Extended Control And Status Connections

    Installation & Initial Turn-On 2.7.1 Remote/Extended Control and Status Connections Input control lines are standard ground switching inputs. The inputs can be operated by relay contact or transistor switching. See Figure 2-12. Grounds are provided on TB1 for use as common. Figure 2-12 Ground Switching for Remote Control The status output lines on TB1 are transistor type - open collector.

  • Page 45: Typical Remote/Extended Control And Status Connec

    Installation & Initial Turn-On NOTE: Maximum status line current is 25 mA. If the output is used to drive a small printed circuit board type relay, check current requirements for relay coil and be sure to install a circuit protection diode across the coil. A 1N4004 or equivalent will work.

  • Page 46: Extended Metering

    Installation & Initial Turn-On 2.7.1.2 Extended Metering Extended metering can also be connected to TB1 terminals. See Figure 2-15 for typical extended metering connections. Figure 2-15 Extended Metering 2.7.2 UPS IN/Remote Exciter Select, Configurable Input TB1-9 The remote input at TB1-9 is a software configurable input which is set via the Diagnostics Display Menu.

  • Page 47: Using An Uninterruptable Power Supply Or Ups

    Installation & Initial Turn-On Using an Uninterruptable Power Supply or UPS If the transmitter is backed up with a UPS, to keep it operating during an AC power failure, then the logical thing to do is to lower the transmitter power to conserve the UPS for as long as possible.

  • Page 48: Optimizing Efficiency

    Installation & Initial Turn-On Optimizing Efficiency The transmitter has the ability to Manually or Automatically optimize its own operating efficiency. It is not a requirement, and the transmitter will meet all specifications without activating this function. When activated, the controller will adjust the transmitter operating parameters to get the best possible efficiency.

  • Page 49: Setting The Low Power Alarm

    Figure 2-20 Remote Low Power Alarm Set [HOME, MORE, CONFIGURATION B,D,B 2.11 Jumper Settings for Installation of a Harris Exciter The following is for installing an exciter other than the one (or two) which came with the transmitter. Any exciter tested and shipped with the transmitter will have already been configured properly for the transmitter and should not require any jumper changes (Mounting kits are available for each of the exciters).
  • Page 50 Installation & Initial Turn-On Table 2-1 TB1 Remote Control Interface Connections 2-30 888-2406-002 WARNING: Disconnect primary power prior to servicing.
  • Page 51 Installation & Initial Turn-On Table 2-1 TB1 Remote Control Interface Connections (continued) 888-2406-002 2-31 WARNING: Disconnect primary power prior to servicing.
  • Page 52 Installation & Initial Turn-On Table 2-2 Jumper Settings for Installing a Harris Exciter 2-32 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 53: Power Distribution For Optimum Transmitter

    Performance This section is applicable to the three phase supplies only, as well as other three phase equipment. For many years HARRIS engineers have recommended that the three phase power distribution system should be either a closed delta or WYE configuration to provide better radio and television transmitter performance by helping prevent line unbalance.

  • Page 54: The Causes Of Line Unbalance

    For this reason, along with their inherent susceptibility to transients, Harris does not recommend the use of open delta systems. Figure 2-21 3 Phase Closed Delta vs. Open Delta...

  • Page 55: Three Phase Wye Distribution Transformers

    Installation & Initial Turn-On There is another problem which can occur with an open delta system, and that is caused by lightning and switching transients. When lightning strikes or heavy loads are switched on a power distribution system, high voltage transients are propagated throughout the system.
  • Page 56 Installation & Initial Turn-On Today, many transformers are supplied with all of the primary terminals available so that either a delta or WYE connection can be made. Table 2-4 shows the different line-to-line voltages that are available with this configuration. Table 2-3 Typical Line Voltages, Delta or WYE Delta Connected WYE Connected...

  • Page 57: Operator Guide

    Operator Guide Introduction This section contains normal operational procedures and information pertaining to the function of the Platinum Z2 FM Transmitter. Most important, is the information regarding use of the Diagnostic System. All of the information in this section assumes the transmitter and controller are in proper working order. Figure 3-1 Controller Front Panel 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 58: Transmitter Controls

    Operator Guide Transmitter Controls The transmitter controls are mostly on the right half of the controller front panel at the top of the transmitter, See Figure 3-1. These controls and their function are listed below. OFF - Used to turn the transmitter off ON - HIGH - Turns the transmitter on to the previous HIGH setting.

  • Page 59: Transmitter Metering

    Operator Guide Transmitter Metering There are five function keys below the Transmitter display on the front of the controller: 1. FWD PWR (Forward Power) 2. RFL PWR (Reflected Power) 3. PA Amps 4. PA Volts 5. APC (Automatic Power Control) These are dedicated metering selections for the 5 most important transmitter parameters.

  • Page 60: Using The Diagnostic Display

    Operator Guide Using the Diagnostic Display The Platinum Z Series transmitters utilizes a very unique and powerful diagnostic system. The diagnostic system is actually your interface to the inner workings of the transmitter. It is used for Status, Metering, Fault Logging, Configuration and even hardware and software Testing of the controller.

  • Page 61: Home

    Operator Guide 3.4.1 HOME HOME takes you to the home layer or root menu. This menu should look like the one in Figure 3-3, which is the first of two screens in this layer. The second screen in the HOME layer is accessed by pressing the “D” function key to the right of the display which is labelled “MORE -”...

  • Page 62: Back

    Operator Guide 3.4.2 BACK BACK takes you to the previous layer in the menu tree, not necessarily to the previous screen. As an example, if you were to press HOME and then choose STATUS you would now be in layer 2 of the STATUS menu. You should see the screen shown in Figure 3-5.

  • Page 63: Diagnostic Codes

    Operator Guide 3.4.4 Diagnostic Codes For ease of discussion a simple code will be used to guide you to the area or screen being discussed. The code will have the name of one of the HOME menu items listed above, followed by the appropriate A, B, C or D function key presses required to get to the screen being discussed.

  • Page 64: Asterisk And Pound Signs(*, #)

    Operator Guide Example 2 You want to check or possibly change the Maximum High Power Setting. This falls under the category of CONFIGURATION, but this menu item only shows up on the second screen of the HOME layer. Therefore, press the following keys: [HOME, MORE, CONFIGURATION B,B] This should have taken you to the screen shown in Figure 3-7.

  • Page 65: Fault Logging

    Operator Guide 3.4.6 Fault Logging The Fault Log is located under “Fault” in the Main Menu. Pressing Fault will take you to the screen shown in Figure 3-8. This screen gives you a choice of resetting the transmitter faults and fault log (and clearing any red indicators) or viewing the Fault Log.

  • Page 66: Emergency Operating Procedures

    Operator Guide Emergency Operating Procedures WARNING: THE PA MODULES ARE DESIGNED TO HANDLE VERY HIGH TEMPERATURES AND MAY BE EXTREMELY HOT. DO NOT TOUCH THE MODULES WITH BARE HANDS AFTER THE TRANSMITTER HAS BEEN RUNNING, ESPECIALLY IN HIGH AMBIENT TEMPERATURE ENVIRONMENTS. 3.5.1 Multiple PA Failures in a Foursome If two PAs were to fail in a single group of four or Foursome, the resulting system...

  • Page 67: Manual Exciter Switching

    Operator Guide Manual Exciter Switching The active exciter (if dual exciters are installed) can be switched manually from the Status menus in the Diagnostics Display. To manually switch from Exciter 1 to Exciter 2 press [STATUS D,C]. This will bring up the screen shown in Figure 3-10. Pressing [D] will toggle between the two Exciters.

  • Page 68: Optimizing Efficiency

    Operator Guide Optimizing Efficiency The transmitter has the ability to Manually or Automatically optimize its own operating efficiency. It is not a requirement, and the transmitter will meet all specifications without activating this function. When activated, the controller will adjust the transmitter operating parameters to get the best possible efficiency. The user must select whether the function is in Manual or Automatic mode via the Diagnostics Display Menus, see Figure 3-12.

  • Page 69: Fan Speed

    Operator Guide NOTE: The REF Voltage in Figure 3-13 is merely an internal reference point the con- troller uses to reduce the wupply voltgae in optimized mode. THis reading is usually in the low 40’s when the transmitter is optimized (well below the actual supply voltage).
  • Page 70 Operator Guide 3-14 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 71: Overall System Theory

    Overall System Theory Introduction This section contains theory of operation and circuit descriptions of the Platinum Z2™ FM Broadcast Transmitter. The Platinum Z2™ has two possible designations: • Z2CD, which is a 2kW FM transmitter supplied with the DIGIT, digital FM exciter.
  • Page 72 Overall System Theory Figure 4-1 RF Flow Block Diagram 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 73: Exciters

    Overall System Theory 4.2.1 Exciters It starts with the built in dual exciter option (in other words the switching components are present but the exciter is optional). The RF output of both exciters (if present) connect in to the Exciter/IPA Backplane board. The exciter RF switch shown on this board is activated by the controller if Exciter A were to fail, placing Exciter B on the air automatically.

  • Page 74: Z-Plane Combiner Board

    Overall System Theory 4.2.3.2 Z-Plane Combiner Board The Combiner Board receives the outputs from the 8 PAs and combines them in two 4 Way Isolated Wilkinson Combiners, whose outputs are then combined in a 2 way Wilkinson combiner for a 2.5kW nominal output. Each PA is capable of delivering up to 425 watts into a good load, but will be operating at approximately 325 watts nominally for 2kW of combined transmitter output.

  • Page 75: Detailed Rf Theory Of Operation

    Overall System Theory Detailed RF Theory of Operation The exciter theory is described in a separate technical manual included with the transmitter. Each of the remaining RF sections of the transmitter are described in the following paragraphs. 4.3.1 Exciter Operation The exciter output is basically fixed and should not require adjustment.

  • Page 76: Ipa

    Overall System Theory 4.3.2 The IPA amplifier and/or module is identical to any one of the PA modules except that it has an amplifier on each side of the module whereas the PA modules only have a single PA mounted on the module heatsink (the opposite side is empty). This allows a PA module to be used in place of a failed IPA.

  • Page 77: Main/Alternate Exciter Switching

    Overall System Theory 4.3.3.1 Main/Alternate Exciter Switching Exciter selection is done via relay K1 and the EXCITER SELECT control signal from the Life Support Board. The EXCITER SELECT signal is normally low which places K1 in the position shown on the schematic, sending the Exciter 1 RF output to the IPA input relay K2.

  • Page 78: Ipa Monitoring

    Overall System Theory 4.3.3.3 IPA Monitoring The IPA Backplane Board provides for monitoring and/or interfacing of 4 main IPA parameters: • IPA temperature (VTEMP_IPA1 and/or VTEMP_IPA2). If the IPA board exceeds 100°C, the controller will mute the transmitter and/or switch to the alternate IPA. The sensor is actually located on the IPA board, but is interfaced through the Backplane.

  • Page 79: Ipa Power Divider (3Db Hybrid)

    Overall System Theory 4.3.3.6 IPA Power Divider (3dB Hybrid) The IPA power divider is actually a 3dB hybrid which is used in the Z5 and Z10 transmitters to split the IPA output into 2 equal amplitude signals 90 degrees out of phase to drive Z Planes A and B.

  • Page 80: 8-Way Combiner

    Overall System Theory 4.3.4.2 8-Way Combiner Refer to the Combiner schematic for the following. Each 8-way combiner consists of two 4-way Wilkinson combiners, called FOURSOMES, followed by a 2-way Wilkinson combiner which combines the outputs of the two Foursomes. The Foursomes are split up as follows: •...
  • Page 81 Overall System Theory IPA_2 IPA_1 Figure 4-4 PA Compartment Front View Figure 4-5 PA Compartment Rear View 888-2406-002 4-11 WARNING: Disconnect primary power prior to servicing.

  • Page 82: Power Amplifier (Pa)

    Overall System Theory 4.3.4.4 Power Amplifier (PA) The RF drive from the IPA enters the PA Amplifier Boards at Pin C. The RF input level for each amplifier is typically 15-20 watts. TL1, C1 and C2 allow the input impedance to be matched to 50 ohms and permit the phase shift through the module to be trimmed to a nominal value which allows all modules to combine in-phase.
  • Page 83 Overall System Theory Maximum RF output is 425 watts. Typical output level is 300 to 340 watts. The power module is designed for single amplifier field replacement. In the event an RF power MOSFET fails, field replacement is not practical due to the cost of components, time and test equipment involved in repair and alignment of phase, gain and response.

  • Page 84: Harmonic Filter

    Overall System Theory 4.3.5 Harmonic Filter The vertical transmission line at the rear of the cabinet contains the Harmonic Filter which is connected directly to the output of the Z-Plane via a transmission line connection which is routed under the PA deck and through the power supply compartment.

  • Page 85: Power Supply Block Diagram Description

    Overall System Theory Power Supply Block Diagram Description There are two different types of power supplies in the transmitter, the PA Power Supply and the Low Voltage Power Supply. 4.4.1 PA Power Supply There are three power supply configurations available for the Z2 transmitter: •...

  • Page 86: 3-Phase Power Supply

    Overall System Theory 4.4.1.2 3-Phase Power Supply The Z2 transmitter uses a single main power transformers whose DC outputs are combined through large inductive chokes. Figure 4-8 shows a simplified diagram of the PA power supply transformer. For additional redundancy, the Z2 can be configured with an optional second supply (See Appendix A, Z2 Redundancy Package).
  • Page 87 Overall System Theory 4.4.1.2.1 Soft Start During transmitter turn on, a fifth set of SCRs is activated, See Figure 4-9. These are connected to the lowest voltage output tap (the one with the fewest secondary turns) of transformer secondary “B”. However, the Soft Start SCRs are connected through a common surge limiting resistor to ground, instead of the direct ground connection provided with the rest of the SCRs.

  • Page 88: Single Phase Power Supply

    Overall System Theory 4.4.1.3 Single Phase Power Supply The transmitter has one power supply for the standard Z2 and 2 power supplies for the Z2R (Redundant Package). These are designated PS1 (and PS2 for the Z2R). Figure 4-10 shows the placement of each of the power supplies and connection points for installation or removal of the supplies.
  • Page 89 Overall System Theory Figure 4-11 Simplified Single Phase Power Supply 4.4.1.3.1 Soft Start During transmitter turn on, a fifth set of SCRs is activated (these are located on the Rectifier Boards), See Figure 4-12. These SCRs are connected to the lowest voltage output tap of each transformer secondary (the one with the fewest secondary turns).

  • Page 90: Low Voltage Power Supply

    Overall System Theory 4.4.1.3.1 PA Power Supply Discharge The PA Power Supply Discharge circuit also uses the Soft Start resistor to discharge the 52Vdc PA supply. The discharge circuit is activated when the transmitter is turned off. When the discharge circuit is active, it disables the SCRs to prevent the supply from trying to turn on during a discharge cycle.

  • Page 91: Detailed Power Supply Descriptions

    Overall System Theory Detailed Power Supply Descriptions 4.5.1 3-Phase PA Power Supply Refer to the Overall System Block Diagram in the schematic package for the following discussion. The transmitter 3 phase AC inputs connect directly to K1, the AC mains contactor. The transformer side of the contactor is connected to A17TB1 on the front of the power supply tray.
  • Page 92 Overall System Theory Figure 4-13 Simplified 3-Phase Transformer Secondary 4-22 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 93: Rectifier Board Circuit Description

    Overall System Theory 4.5.1.2 Rectifier Board Circuit Description Refer to the Rectifier Board schematic and Figure 4-13 for the following. The Rectifier Boards perform three primary functions: • Dynamic secondary tap switching using SCRs, to maintain a relatively constant supply voltage and thus maintain constant transmitter power output despite fluc- tuations in the 3 phase AC line voltage.
  • Page 94 Overall System Theory Diagram for these connections). Note that both the “A” and “B” side SCRs have selected the same relative (lowest voltage) taps on each of the two transformer secondaries. 4.5.1.2.2 PA Power Supply Soft-Start Soft-Start is used to limit the surge current during transmitter turn on. The Soft Start and PA Power Supply Discharge circuits are able to use the same resistor, R48 since only one or the other will be active at any one time.

  • Page 95: Single Phase Pa Power Supply

    Overall System Theory To determine if a tap has failed (blown fuse), refer to the Diagnostics Display. For Power Supply 1, Press [STATUS, D,A,A,D] This will show you the screen in Figure 4-14. Figure 4-14 Power Supply Tap Status 4.5.2 Single Phase PA Power Supply Refer to the Overall System Block Diagram in the schematic package for the following discussion.

  • Page 96: Rectifier Board Circuit Description

    Overall System Theory secondary turns in circuit and will therefore give the lowest DC output voltage. This means that the taps which are furthest from the center will give the highest DC output voltage due to more active turns in the secondary. 4.5.2.2 Rectifier Board Circuit Description Refer to the Rectifier Board schematic for the following.
  • Page 97 Overall System Theory transformer secondaries. Note that both power supplies have selected the same relative (lowest voltage) taps on each of the transformer secondaries. 4.5.2.2.2 PA Power Supply Soft-Start Soft-Start is used to limit the surge current during transmitter turn on. The Soft Start and PA Power Supply Discharge circuits are able to use the same resistor, R48 since only one or the other will be active at any one time.

  • Page 98: Power Supply Id Jumpers

    Overall System Theory 4.5.2.2.5 Low Voltage Supply Regulators U1, U3 and U4 regulate the voltages from the Low Voltage Supply down to 7.1Vdc, +20Vdc and -20Vdc respectively. These voltages are sent to the controller where they will be distributed to the individual controller boards. Input voltages to these regulators will vary depending on the AC mains voltage.

  • Page 99: Low Voltage Power Supply Board

    Overall System Theory 4.5.4 Low Voltage Power Supply Board The AC input for this board is dependant on the AC voltage and configuration for the transmitter, 3-phase Delta (3 wire), 3-phase WYE (4 wire) or single phase. The same board is used in all three cases. The AC inputs to the board come from circuit breaker, CB1, and enter the board at J1-1 and J1-4.

  • Page 100: Cooling System Description

    Overall System Theory Cooling System Description The transmitter is cooled by the single, two speed fan in the lower rear of the transmitter. It uses a high volume, low velocity, air system. Air ducting for inlet air should be well filtered and, if possible, at a slightly positive pressure. The exhaust air ducting should cause very little or no back pressure due to the low velocity air system.

  • Page 101: Master Controller

    Overall System Theory The Controller functions include: • Transmitter Control Functions • Automatic Power Control, or APC • VSWR Monitoring and Overload Protection • Power Supply Monitoring and Protection • Power Amplifier Monitoring and Protection • Automatic power foldback for VSWR, Over-temperature and Over-current con- ditions.

  • Page 102: Apc, Automatic Power Control

    Overall System Theory All the individual bits or bytes of information stored here have a default setting which is stored in the firmware ROM. When the information in U39 is uploaded to RAM it is checked against the default values. If it is considered to be out of tolerance (or invalid data) it will automatically be replaced with the default value from the ROM.
  • Page 103 Overall System Theory The APC loop starts at the forward power directional coupler. The forward sample is connected to the Life Support Board where it is calibrated with R127 for 8.9V@ 100% TPO at TP9. This voltage sample is then sent to the Master Controller (schematic sheet 7) where it is squared by multiplier chip U1 (to make the voltage from the coupler proportional to power) and divided by 10.

  • Page 104: Calibration Factors And A/D Values

    Overall System Theory Example 3 The following is an example of how the entire loop would work. For our example the power output of the transmitter goes down due to a failed PA. This would decrease the output of the forward power directional coupler and the voltage at the input to the difference amp at U5-6 on the Master Controller Board.
  • Page 105 Overall System Theory Calibration Factors: • Forward Factor - 0.003079 • Reflect Factor - 0.000123 • APC_Factor - 3.03 • EXC_Factor - See Factory Test Data (Frequency dependent) • IPA_Factor - See Factory Test Data (Frequency dependent) A/D Readings • DAC_APC_REF - 660 (nominal) •...

  • Page 106: Dac_Apc_Ref

    Overall System Theory The following is a description of each of these parameters. 4.7.2.1 DAC_APC_REF DAC_APC_REF [HOME, MORE, CONFIGURATION C,B] is a counter (internal to the micro), whose output will be between 0 and 900, that is controlled by the RAISE and LOWER buttons on the front panel.

  • Page 107: Apc Factor

    Overall System Theory The Forward Factor is now used for all forward power level settings. For example, to set the Low power control to 1kW you press the lower button. This gradually lowers the transmitter power output by reducing the DAC_APC_REF and therefore the APC_REF voltage and transmitter power.

  • Page 108: Max High, Max Low And Ups Power Levels4-38

    Overall System Theory 4.7.2.4 MAX HIGH, MAX LOW and UPS Power Levels MAX HIGH, MAX LOW and UPS power levels are set using the Diagnostics Display and stored in the EEPROM, U39. MAX HIGH SET screen [HOME, MORE, CONFIGURATION B,B] sets the maximum power level when the HIGH ON button is pressed.

  • Page 109: Exc Factor And Ipa Factor

    Overall System Theory This is now the highest possible number for the DAC_APC_REF and will limit the transmitter power to 2.4kW.To prove that: FWD PWR = APC Factor * DAC_APC_REF FWD PWR = 3.03 * 792 = 2.4kW 4.7.2.5 EXC Factor and IPA Factor When the transmitter Forward Power is calibrated, the micro samples the exciter and IPA outputs and sends the A/D readings to the screen as: •...

  • Page 110: Vswr Foldback

    Overall System Theory A/D_RFL_PWR = SQRT(RFL_PWR / Reflect Factor) A/D_RFL_PWR = SQRT(80W / 0.000123) = 806 (Fault) or A/D_RFL_PWR = SQRT(44W / 0.000123) = 598 (Foldback) VSWR protection is based on this A/D reading, which is directly proportional to a reflected power level, not on a calculated VSWR reading.

  • Page 111: Master Controller Faults

    Overall System Theory 4.7.3.1 Master Controller Faults For a complete listing of all of the faults associated with the Master Controller refer to Section VI, Troubleshooting. 4.7.3.1.1 3 Strike Routine There are 2 faults in the transmitter that will initiate what is called a 3 strike routine. They are: •...

  • Page 112: Pa Controller Board

    Overall System Theory 4.7.4 PA Controller Board The PA Controller Board utilizes a micro-controller which reports to the Master Controller, but operates independently of the Master. The board ID is set via DIP switches to make it PA Controller #1. The Backplane Board has slots for up to 4 PA Controllers which are used for the higher power Z Series transmitters such as the Z5 and Z10.

  • Page 113: Crossover (Xover) Protection (Z2R Only)

    Overall System Theory • PA Current - The current draw of each PA is monitored by measuring the voltage drop across 0.01 ohm resistors, R11-R18, on the Z-Planes. The resistors show up as part of the Divider Schematic. This allows the current of each individual PA to be available on the Diagnostics Display.

  • Page 114: Pa Controller Faults

    Overall System Theory 4.7.4.4 PA Controller Faults For a complete listing of the faults associated with the PA Controllers refer to Section VI, Troubleshooting. 4.7.5 Power Supply Controller There is only one PS Controller Board and one power supply in the standard Z2 transmitter.

  • Page 115: Pa Power Supply Discharge

    Overall System Theory sequence will be aborted. After 3 (or 6) seconds, if the voltage is within tolerance, the PS Controller will activate the lowest available voltage tap by activating one of the four DRIVER signals. Since DRIVER_1 is connected to the 48V tap, it will be activated first (if available) and the power supplies will come up to full charge.

  • Page 116: Reset

    Overall System Theory A sample of the voltage across the discharge resistor is sent to the PS Controller at J1-20 and J2-20. If the voltage is more than 30Vdc, the comparator will trip, and the output at U1-1 or U1-2 will go LOW. The fault signal 1_DISCH_SAMPLE is then sent to U9-2 where it is buffered before reaching the micro-controller.

  • Page 117: Ps Controller Faults

    Overall System Theory 4.7.5.8 PS Controller Faults For a complete listing of all of the faults associated with the PS Controller refer to Section VI, Troubleshooting. 4.7.6 Life Support Board The Master Controller is backed up by the Life Support Board. The Life Support Board allows safe transmitter operation at reduced power if the Master Controller is not operating.
  • Page 118 Overall System Theory 4.7.6.1.1.1 Pulse Stretcher, U4 U4 is a pulse stretcher which will output a 100mSec pulse whenever the transmitter ON button is pressed. Provided there is no power failure signal, POWERFAIL(BAR) from U37-7, The 100mSec pulse from U4-10 will pass through to U6-13, U8-12 and leaves the board to reset the PA and PS Controller Boards at J1-A83.
  • Page 119 Overall System Theory 4.7.6.1.1.4 CONTACTOR_ON(BAR), K4-4 The signal at K4-4 is called CONTACTOR_ON(BAR) and ties to several places, U33-12, U30-12, and U30-10. This signal is low when K4 is in the SET position and the contactor is engaged. a. The CONTACTOR_ON(BAR) signal at U33-12 is only used during Life Support Mode.
  • Page 120 Overall System Theory SUPPLY_DISABLE at U30-11 to shut off the power supply and a SYSTEM_MUTE via U30-10 which will mute the exciter and IPAs. 4.7.6.1.2.1 Remote Transmitter Turn OFF REM_OFF(BAR) is activated via the remote control interface. When the remote control pulls this line low, it will activate optical isolator, U23, bringing U23-6 low.
  • Page 121 Overall System Theory 4.7.6.1.3 External Interlock The External Interlock input can be used for any purpose which requires shutting off the transmitter, such as a protective door being opened or a water (or air) switch on a dummy load. The primary purpose is for the protection of personnel. a.
  • Page 122 Overall System Theory a. PA_CTRL#_MUTE. This a mute command from the PA Controller Boards which will be triggered by various events such as a PA being removed or inserted (# is a number from 1-4). b. MASTER_IPA_MUTE. c. FAILSAFE. Discussed earlier. d.

  • Page 123: Power Control

    Overall System Theory • The low from K2-4 goes off the board to the IPA Backplane Board where it actu- ates the IPA select relays, K2 and K3 to the position shown on the schematic. It also goes to the Master Controller as a status signal, so it knows which IPA is selected.

  • Page 124: Life Support Mode

    Overall System Theory 4.7.6.1.9 Forward Power Sample The forward power sample from the directional coupler enters the Life Support Board at J2. The sample is detected by CR8 and buffered by U1-14. The DC voltage at TP8 is directly proportional to the forward power output of the transmitter. This is sent to the Master Controller where it is used for monitoring, display, automatic power control or APC and calibration.
  • Page 125 Overall System Theory 4.7.6.2.1.1 MASTER_NORMAL This signal goes low when the Master Controller fails and only has one function. It is the control signal for U5-13, an analog switch. The input to the switch at U5-1 is the analog control signal, MSTR_IPA_CTL from the Master Controller APC circuit, which controls the IPA gate voltage and therefore the power output of the transmitter.
  • Page 126 Overall System Theory e. MSTR_NORMAL 1 applies a low to NAND gate U7-2 causing U7-3 to go high. This enables the direct connection of the front panel overlay buttons to the on and off logic by enabling U26-13 and U26-2, bypassing the control cir- cuits on the failed Master Controller.
  • Page 127 Overall System Theory c. MASTER_NORMAL(BAR) applies a high to the CLEAR line of U8-3. This enables U8-6, the Q output, to apply a 3 second SOFTSTART_MUTE after a power failure. The POWERFAIL(BAR) signal comes from U37-7 and is a minimum 200mSec low pulse. U37 is monitoring the +20Vdc supply and will bring pin 7 low if the voltage drops below +12Vdc.
  • Page 128 Overall System Theory 4.7.6.2.2 Reflected Power The reflected power sample enters the board at J3. It is detected by CR10 and buffered by U1-1. The voltage at TP7 is directly proportional to the amount of reflected power coming back to the transmitter from the antenna or transmission line.
  • Page 129 Overall System Theory Table 4-1 PA Control Distribution Standard Z2 PA Designations Related Related PA Designations on PA on Combiner and Isolation Isolation Controller Schematic Divider Schematic Relay # Resistor # PA Designations PA5 (J5) PA6 (J6) PA7 (J7) PA8 (J8) Z-PLANE PA4 (J4) PA3 (J3)
  • Page 130 Overall System Theory 4-60 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 131: Maintenance And Alignment

    Maintenance and Alignment Introduction This section provides maintenance and alignment information, for the purpose of routine maintenance and replacement of PC boards and other major components of the Platinum Z2 FM BROADCAST TRANSMITTER. Routine Maintenance Routine maintenance of the Platinum Z series transmitter basically consists of regular cleaning and monitoring of temperatures, currents, voltages and faults.

  • Page 132: Transmitter Logbook

    Maintenance and Alignment 5.2.2.2 Transmitter Logbook As a minimum performance characteristic, the transmitter should be monitored (using front panel metering and the Diagnostic Display) and the results recorded in the transmitter logbook at least once a day. 5.2.2.3 Maintenance Logbook The maintenance logbook should contain a complete description of all maintenance activities required to keep the transmitter operational.

  • Page 133: Module Cleaning

    Maintenance and Alignment 5.2.3.1 Module cleaning The heatsinks on the modules are high efficiency, and therefore do not have large openings for airflow and will tend to collect dirt over time. The modules should be cleaned with compressed air on a schedule to be determined on site, depending on the air system, filtering, humidity etc...

  • Page 134: System Test

    Therefore the resistors and thermistors, labeled RT1 - RT8, must be obtained from Harris, pre-assembled. De-soldering on the Isolation Board requires a lot of heat due to the large amount of ground plane. If the resistors are not heated and removed properly, the PC board will be damaged and the feed- throughs pulled out.

  • Page 135: Isolation Board Removal

    Maintenance and Alignment 5.5.1 Isolation Board Removal There are 2 ribbon cables connecting to the Isolation assembly. The STEP 1 cables should be disconnected from the RFI filter board. They can be removed from the Isolation Board once it is removed from the transmitter.

  • Page 136: Installation Of Isolation Assembly

    Maintenance and Alignment NOTE: The resistors should be ordered as an assembly, with the thermistor already attached as this is very critical to proper transmitter operation. 5.5.1.2 Installation of Isolation Assembly If a new Isolation Board is being installed be sure to set the ID jumpers to the proper location as marked on the PC Board next to the jumper pins.

  • Page 137: Directional Coupler Removal And Replacement

    Maintenance and Alignment Directional Coupler Removal and Replacement First, note that 2 of the couplers are labeled Forward sampling and one is Reflected. They cannot be interchanged as the coupling ratio is different. The difference is how far the coupler is inserted into the base. The Forward couplers are not inserted as far as the reflected and have a small gap between the coupler and the base.

  • Page 138: Setting Maximum Power Limits

    Maintenance and Alignment Setting Maximum Power Limits There is a maximum power limit which can be set for each of the transmitter power settings, LOW and HIGH. The “MAX HIGH SET” sets the maximum power output when the transmitter is on HIGH power. The “MAX LOW SET” sets the maximum power output when the transmitter is on LOW power.

  • Page 139: Setting Fwd Pwr To Display 100

    Maintenance and Alignment Setting FWD PWR to Display 100% This procedure simply makes the transmitter FWD PWR % meter read 100% at the present transmitter power output (this will not change the kW reading on the FWD PWR display). Changing TPO does not require re-calibration and is accomplished with the following 2 steps: Set the power to the desired TPO using the raise and lower buttons.

  • Page 140: Forward Power Calibration

    Maintenance and Alignment 5.11 Forward Power Calibration If at all possible, it is recommended that the transmitter be calibrated at the full 2kW power level, even if your TPO is different. This restores all of the calibration parameters to the same relative values as were set up in the factory. It will also assure that the transmitter will be able to reach its full 2kW power output if so desired (this is a user defined level which is set by the MAX HIGH SET in the configuration menus).
  • Page 141 Maintenance and Alignment Figure 5-3 APC Calibration Factor Screen [HOME, MORE, CONFIGURATION C,A,D,C] Set R127 on the Life Support Board maximum CW. STEP 6 Turn the transmitter on. Make sure the exciter is on and un-muted. STEP 7 Exciter power should be about 24 watts, see factory test data to verify. Press [HOME, MORE, CONFIGURATION C,B].
  • Page 142 Maintenance and Alignment Figure 5-5 Forward Power CAL Screen [HOME,MORE,CONFIGURATION C,C] Set the Transmitter LCD meter (the right-hand display) to read FWD STEP 11 PWR in kW. Calibrating - Verify once more that the FWD POWER CAL screen STEP 12 and the external power meter agree.

  • Page 143: Reflected Power Calibration

    Maintenance and Alignment 5.12 Reflected Power Calibration This procedure can be done using the forward power reading on the transmitter. If the forward power also needs to be calibrated, an external meter will have to be used. Shut the transmitter off. Turn R128 on the Life Support Board STEP 1 maximum CCW.
  • Page 144 Maintenance and Alignment Raise the transmitter power very slowly until the Forward Power STEP 7 meter reading is 60 watts (or 00.06 kW). If Forward Power is not yet calibrated, then an external meter will have to be used. Press [HOME, MORE, CONFIGURATION C,B]. You should now STEP 8 be at the screen shown in Figure 5-7, A/D RFL PWR.

  • Page 145: Pc Board Replacement Procedures

    Support Board. JP1 and JP2 select the main and alternate exciter mute as active HIGH or LOW. Table 2-2 shows the proper settings for a Harris exciter. JP3 should be set from pins 1-2 for a Z2. Be careful to mark and note where all cables connect to the defective STEP 4 Life Support Board before removing.
  • Page 146 Maintenance and Alignment Turn on the AC at the wall breaker but do not turn the transmitter on STEP 6 yet. Make sure CB1, the circuit breaker in the rear of the transmitter is also turned on. Setting the +5V REF - with a digital voltmeter, check TP4, the +5V STEP 7 REF(reference).

  • Page 147: Replacing The Power Supply Controller Board

    Maintenance and Alignment 5.13.2 Replacing the Power Supply Controller Board Replacement of a PS Controller Board requires no analog adjustments. Set all dip switches and jumpers to the same position as the board being replaced. If the new board does not have the firmware IC’s already installed, then the firmware will have to be transferred from the old board.

  • Page 148: Replacing The Master Controller Board

    Maintenance and Alignment 5.13.4 Replacing the Master Controller Board In the unlikely event that the Master Controller Board needs to be replaced, there are two possible scenarios: a. Replacement using EEPROM U39 from the old board. This procedure should be tried first. b.

  • Page 149: Replacing Eeprom U39

    Maintenance and Alignment NOTE: To verify the most important configuration parameters, follow the steps listed under “Configuration,” later in this section, before continuing. Turn the transmitter on and check the calibration. If the transmitter STEP 8 calibration and configuration seem to be okay, then this procedure is finished.
  • Page 150 Maintenance and Alignment • S1-9 OFF (ON = Microcontroller RESET) • S1-10 ON (APC ON) Turn on the Low Voltage breaker in the rear of the transmitter. If the STEP 6 EEPROM is blank, the Fault Log will register EEPROM_DEF which means it loaded the default settings for the EEPROM (shown in Table 5-1).

  • Page 151: System Configuration And Calibration

    Maintenance and Alignment 5.14 System Configuration and Calibration System configuration and calibration is mainly for setting the transmitter up for the first time by factory personnel. The procedures contained here should NOT be done as part of a routine maintenance or adjustment schedule. The following procedure should only be done if EEPROM U39 on the Master Controller Board is bad or suspect (EEPROM U39 is the memory chip which contains all of the transmitter configuration and calibration settings).
  • Page 152 Maintenance and Alignment • UPS/EXCITER. This is the configurable remote input at TB1-9. Set for UPS if the low power UPS mode is to be used, or to EXC if it is going to be used to remotely switch exciters. •...

  • Page 153: Calibration

    Maintenance and Alignment 5.14.2 Calibration To finish replacing the Master Controller EEPROM U39 a complete calibration is required. To calibrate the transmitter refer to the following procedures in this order: • Reflected Power Calibration, then • Forward Power Calibration WARNING: REFLECTED POWER CALIBRATION MUST BE COMPLETED FIRST TO PROVIDE VSWR PROTECTION DURING THE FORWARD POWER CALIBRATION PROCE- DURE.
  • Page 154 Maintenance and Alignment Firmware IC Removal: • Shut off the Low Voltage breaker in the back of the transmitter. • Pull out the controller and remove the pc board hold-down bracket. • It will be necessary to remove the appropriate PC board and place it on an anti- static work surface (a large anti-static bag works well if an anti-static mat is not available).
  • Page 155 Maintenance and Alignment Table 5-2 Z2 Recommended Minimum Transmitter Log Readings 888-2406-002 5-25 WARNING: Disconnect primary power prior to servicing.
  • Page 156 Maintenance and Alignment 5-26 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 157: Troubleshooting

    Troubleshooting Introduction In order to assist in the troubleshooting of the Platinum Z2 transmitter this section will concentrate in the following areas: • Using the Diagnostics Display System, concentrating on the Fault Log. • Defining all of the transmitter fault indications, their origin, and their effect on the transmitter.

  • Page 158: Power Amplifier Repair

    ING AT THE LOCATION OF THE USER. IT MUST NEVER BE THROWN OUT WITH THE GENERAL OR DOMESTIC WASTE. Defective PAs should be exchanged by contacting the Harris, Service Parts Department (available 24 hours a day 7 days a week).

  • Page 159: Multiple Pa Failures In A Foursome

    Troubleshooting Table 6-1 Transmitter Power vs. Module Failures Platinum Z2 (*Z2R) Component Not Operating Best Case Power Out Worst Case Power Out 1 PA Failed or Removed 100% 100% 2 PAs Failed or Removed 100% 3 PAs Failed or Removed *1 Power Supply Failed *1 PA Controller Failed *Only Applies to Z2R (Redundancy Package)

  • Page 160: Software Revision

    Diagnostics Display Menu labeled, “SOFTWARE REV.” To check the software revisions press [MORE, SOFTWARE REV]. This will bring up the screen shown in Figure 6-1. Before calling Harris Technical Support personnel it is a good idea to get the software revisions for each of the controller boards.

  • Page 161: Strike Routine

    Troubleshooting 6.4.1 3 Strike Routine There are 2 faults in the transmitter that will initiate what is called a 3 strike routine. They are: • RFL_PWR - VSWR greater than 1.5:1 • ISO_BZ_OT - The predicted temperature of R9 on the “B” Z-Plane Isolation board is greater than 130 •...

  • Page 162: Diagnostics Display Menu Tree

    Troubleshooting Diagnostics Display Menu Tree The most important documentation concerning the Diagnostics Display is the “Diagnostics Display Menu Tree” located in the schematic drawing package. This shows the complete Diagnostics Display menu structure. The menus flow from the Main Menu at the left (on each sheet) up to 6 layers deep to the right. Due to the number of menu screens, the drawing is divided by main menu items into 3 drawings.

  • Page 163: Front Panel Fault Led

    Troubleshooting 6.6.1 Front Panel Fault LED When a fault is detected the Fault LED on the front panel of the controller will illuminate a steady red as long as there is an active fault. If there are faults in the log, but none are active, the Fault LED will flash to alert the technician to check the Fault Log.

  • Page 164: Fault Listing

    Troubleshooting • COMM - Communications • XOVER - Crossover Protection: One PA Controller crosses over to protect the PAs controlled by another PA Controller, should it become inoperative (only used with optional Z2 Redundancy Package). • PSC - Power Supply Controller •...

  • Page 165: System Test

    Troubleshooting Figure 6-4 Diagnostic Test Menu 6.7.1 System Test The purpose of the SYSTEM test is to check the combiner configuration, cabling and integrity. The length of time required for the SYSTEM test will be indicated on the display. The test will reduce the transmitter power to 50% of nameplate TPO (1kW) and will be going through a MUTE cycle for each PA.

  • Page 166: Pa Muting Test

    Troubleshooting This test should be used as part of a routine maintenance program at least once a year. It should also be done if major combiner components are removed and/or replaced, such as a Z-Plane or Isolation Board or if cabling is disconnected and re- connected to the Z-Plane or Isolation Board.

  • Page 167: Pa Rf Switch Test

    Troubleshooting d. The thermistor has come loose from the resistor. Each thermistor is attached to the resistor which a high temp epoxy. If this has come loose the thermistor would not heat up as it should. With the transmitter on and operating nor- mally, check the ISO temperature of the PA reported as bad and see if it is approximately the same as the others on that Z-Plane.

  • Page 168: General Troubleshooting Tips

    Troubleshooting The display will read “Main DAC Test Running.” With the scope probe, mon- itor TB1-36 on the Remote control terminal strip which is labelled “SPARE OUT” or on the Master Controller Board U9-14, or either side of R47. There should be a 28Hz sinewave at about 4Vp-p.

  • Page 169: Master Controller Faults

    Troubleshooting used in the Vg (Gate Control Voltage for the individual PAs) menus and signifies that there has been a crossover (this is a condition where one PA Controller crosses over and mutes the PAs associated with another PA Controller). Master Controller Faults The following is a listing of the faults which are handled by or merely related to the Master Controller.

  • Page 170: Ref_Warning, +5V Reference Warning

    Troubleshooting 6.9.3 REF_WARNING, +5V Reference Warning This is simply a warning that the +5Vdc reference voltage, used for system software calibration, is less than 4.75Vdc. No transmitter action is taken other than to report the fault in the fault log and light the Fault LED on the front panel. The +5V Ref can be checked at TP4 on the Life Support Board where it originates.

  • Page 171: Intlk, External Interlock Fault

    Troubleshooting It is also possible that a VSWR fault could be caused by a defective forward or reflected directional coupler or simply from calibration error. An external reflected power meter should be used to verify if there is really a VSWR problem or if it is an internal sensor problem.

  • Page 172: Ups, Uninterruptable Power Supply Fault

    Troubleshooting CAUTION: TURN OFF ALL POWER TO THE TRANSMITTER AT THE WALL BREAKER BEFORE ATTEMPTING TO SERVICE THE BLOWER MOTOR. THE THERMAL PROTECTION, INTERNAL TO THE MOTOR, IS AUTOMATIC. IT WILL SHUT THE BLOWER OFF IF THE MOTOR TEMPERATURE GETS TOO HIGH, BUT IT WILL ALSO AUTOMATICALLY TURN IT BACK ON AFTER A FEW MINUTES AS THE TEMPERATURE GOES DOWN.

  • Page 173: Ipa_Tw, Ipa Temperature Warning

    Troubleshooting 6.9.15 IPA_TW, IPA Temperature Warning If the temperature of an IPA exceeds 85°C the fan will be switched to high speed and IPA_TW will be registered in the Fault Log. There is a 10°C hysterisis so the fan will not switch back to low speed until the IPA reaches 75°C or less. 6.9.16 IPA_OT, Fault If the IPA amplifier temperature exceeds 100°C, as detected by the thermal sensor on the amplifier, the transmitter will initiate a 3 strike routine.

  • Page 174: Amb_Warning, Ambient Temperature Warning6-18

    Troubleshooting 6.9.21 AMB_WARNING, Ambient Temperature Warning If the ambient temperature exceeds 50°C, the controller will switch the fan to high speed. If the temperature goes down after high fan speed is initiated, the fan will go back to low speed when the ambient temperature reaches 45°C (the hysterisis between 50 and 45°C prevents the fan from quickly oscillating between low and high fan speed).

  • Page 175: System Iso Overload (Fault)

    Troubleshooting 6.9.23.2 System ISO Overload (Fault) If the System ISO APC Foldback routine fails to reduce the temperature of the ISO_Bz load and the temperature reaches 145°C, the Master Controller will mute the IPA and the exciter and the PA Controller will mute the PAs. At this point an ISO_Bz fault will be reported in the fault log and the transmitter will mute momentarily.

  • Page 176: Pa Signal Tracing

    Troubleshooting 6.10 PA Signal Tracing Tracing signals from the PA Controller to the PAs can be very confusing. The problem lies in the fact that the PA Controller Boards and the Z-Plane are generic except for the ID jumper settings which designate the board for a specific position. Since the schematics for each of these boards must apply to any position, the labeling is also generic.

  • Page 177: Pa Controller Faults

    Troubleshooting 6.11 PA Controller Faults The following paragraphs give a detailed description of all faults associated with the PA Controller Boards. This mostly deals with the PAs and Isolation resistors. A quick reference of these faults is given in Table 6-2 at the end of this section. 6.11.1 General PA Troubleshooting As a general rule, the first step in troubleshooting any PA (or IPA) problem is to swap the PA or the entire module with another in the transmitter.

  • Page 178: Pa#_Uc, Pa Under-Current Fault

    Troubleshooting 6.11.4 PA#_UC, PA Under-Current Fault PA Under-current is comparing the current readings of the PAs which are common to each foursome. For example, B1, B2, B3 and B4. All four of these PAs are plugged into one 4-way combiner. If one of these PAs has a current reading that is less than 10% of the average current of the other three, the system will be muted for 120mS, the isolation switch for that PA activated, removing the PA from the combiner (removing the PA from the combiner), and the mute released on the rest of...

  • Page 179: Pa_Iso_Ot

    Troubleshooting absorb the imbalance, increasing its temperature. The bigger the imbalance the faster the temperature rises. Each resistor has a thermistor attached to it with a special epoxy to sense the resistor temperature. When 150°C is exceeded (or predicted to do so), the fault log will register a PA#_ISO fault (where # is a number from 1-8), the transmitter will be muted for 120mS, the problem PA will be switched out and the mute released.

  • Page 180: Pa_Iso_Sw, Fault

    Troubleshooting 6.11.11 PA_ISO_SW, Fault This fault will only show up if there is a problem found with the PA ISO Switch during the System Test. During the System Test each PA, and its related ISO resistor, are switched out one at a time. The ISO resistor for that PA should be disconnected and therefore should not increase in temperature.
  • Page 181 Troubleshooting has ID jumpers to select it as Z Plane B. The Isolation Board also has ID jumpers to select it for use with Z Plane B. The ID Jumpers are necessary for the higher power transmitter configurations which have more than one of each of these boards. The ID jumpers prevent cabling errors.

  • Page 182: Power Supply Controller Faults

    Troubleshooting 6.12 Power Supply Controller Faults The following paragraphs give a detailed description of all faults associated with the PS Controller Board. A quick reference of these faults is given in Table 6-3 at the end of this section.There are two types of power supply faults: •...

  • Page 183: Soft Start Circuit Fault

    Troubleshooting 6.12.2.1 Soft Start Circuit Fault This fault is tripped, and the power supply shut off, if the PA voltage does not reach a minimum of 40 volts within 3 seconds (5 seconds for a single phase supply) of activating the softstart circuit. This prevents the SCR’s (other than the soft start SCR’s) from attempting to charge a partially (or perhaps completely) discharged capacitor which would overload the fuses.

  • Page 184: Psc#+20V, Fault

    Troubleshooting • IPA_LOW • EXC#_AFC These faults are incidental and simply occur due to the timing of when the phase loss occurs and which components see it first. 6.12.2.5 PSC#+20V, Fault +20 Volts supply fault. Since this voltage is of paramount importance for the operation of the controller (without it no analog reading can be carried out) it is continuously monitored by the watchdog IC (MAX 705).

  • Page 185: Non Critical Power Supply Faults

    Troubleshooting 6.12.3 Non Critical Power Supply Faults Non-Critical faults provide indications that there is a problem with the power supply which is not serious enough to take any immediate transmitter action, but should be corrected as soon as possible. 6.12.3.1 PS#_TAP#, Power Supply Tap Fault Detection is based on the level of 50/60 Hz ripple at the output of a two stage, DSP based, band pass filter in the PS Controller.
  • Page 186 Troubleshooting Table 6-2 Power Supply Tap Troubleshooting Chart 3 Phase Power Supply Single Phase Supply Rectifier Board "A" Rectifier Board "B" SCRs Fuses SCRs Fuses SCRs Fuses TAP 1 TAP 2 TAP 3 TAP 4 Soft Start There are no Soft Start SCRs on Rectifier Board "A"...
  • Page 187 Troubleshooting Figure 6-7 3 Phase Power Supply Component Locator Top View 888-2406-002 6-31 WARNING: Disconnect primary power prior to servicing.
  • Page 188 Troubleshooting Figure 6-8 Single Phase Power Supply Rectifier Assembly Component Locator, Top View 6-32 888-2406-002 WARNING: Disconnect primary power prior to servicing.
  • Page 189 Troubleshooting Table 6-3 Z2 or Z2R Master Controller Related Faults ABBREVIATION COMMENT ACTION MSTR_REF +5V reference fault. Indicates +5V reference Mute XMTR (IPA & Exciter, Power is < 4.6V supplies) REF_WARNING Indicates +5V Reference is out of tolerance Reports fault in Log without shutting down at the Master Controller Board with error of the PAs.
  • Page 190 Troubleshooting Table 6-3 Z2 or Z2R Master Controller Related Faults ABBREVIATION COMMENT ACTION IPA_LOAD Z-Plane currents are checked during startup Mute XMTR to determine if IPA load is balanced. Most likely caused by bad rf cable. PSC#_COMM Power supply Controller Indication of fault communication to Master PAC#_COMM...
  • Page 191 Troubleshooting Table 6-4 Z2 or Z2R PA Controller Related Faults ABBREVIATION COMMENT ACTION PAC#_REF +5V voltage reference fault (< 4.6V) Mute all PAs for the designated (n = 1 or 2) Transmitter will go to about 20% power as PA Controller and energize all long as only one PA Controller was affected.
  • Page 192 Troubleshooting Table 6-4 Z2 or Z2R PA Controller Related Faults PAC#_J11 Configuration or Cabling fault. Check Mute XMTR cabling and ID jumpers. PAC#_J12 Configuration or Cabling fault. Check Mute XMTR cabling and ID jumpers. PAC#_J1 Configuration or Cabling fault. Check Mute XMTR cabling and ID jumpers.
  • Page 193 Troubleshooting Table 6-5 Z2 or Z2R PS Controller Related Faults ABBREVIATION COMMENT ACTION PSC# +20V +20V DC supply to PSC failed Shut PS OFF and discharge PS#_DSCHG Discharge circuit failed which means Transmitter is shut OFF the PS will not discharge. If discharge resistor is open, a PS#_START fault will prevent the transmitter from being turned on again.
  • Page 194 Troubleshooting 6-38 888-2406-002 WARNING: Disconnect primary power prior to servicing.

  • Page 195: Parts List

    Parts List Refer to separate Acrobat PDF file for Replaceable Parts List information Parts List Index 888-2406-002 WARNING: Disconnect primary power prior to servicing.
  • Page 196 Parts List 888-2406-002 WARNING: Disconnect primary power prior to servicing.

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