Page 1 Timer/Counter/ Analyzer PM6690 Service Manual...
Page 3: General Information
GENERAL INFORMATION Method of Notation This manual contains directions and information that apply to the PM6690 Timer/Counter/Analyzer. In order to simplify the references, the following designation system is used throughout the manual: – PM6690 is abbreviated to '90'. Warranty The Warranty Statement is included in the Getting Started Manual.
Page 4 This page is intentionally left blank.
Page 5: Table Of Contents
Contents Corrective & Preventive Maintenance GENERAL INFORMATION..... III Introduction ....... . 5-2 Safety Instructions Calibration.
Page 6 External Reference Input ....7-13 Internal Reference Oscillators....7-14 RF Input 3 GHz .
Page 7: Safety Instructions
Chapter 1 Safety Instructions...
Page 8: Caution And Warning Statements
Symbols WARNING: These servicing instructions are Shows where the protective ground terminal is con- for use by qualified personnel only. To re- nected inside the instrument. Never remove or duce the risk of electric shock, do not loosen this screw. perform any servicing other than that specified in the Operators Manual unless you are fully qualified to do so.
Page 9 and side panels is not obstructed. Leave 5 centimeters (2 Assembling the Rackmount Kit inches) of space around the counter. – Make sure the power cord is disconnected from the in- strument. Fold-Down Support – Turn the instrument upside down. For bench-top use, a fold-down support is available for use See Fig.
Page 10: Line Voltage
The long bracket has an opening so that cables for Input A, B, and C can be routed inside the rack. Reversing the Rackmount Kit The instrument may also be mounted to the right in the rack. To do so, first remove the plate on the long bracket and fasten it on the short one, then perform the preceding steps.
Page 11: Performance Check
Chapter 2 Performance Check...
Page 12: General Information
Note any error messages. –9 10 MHz, 1 * 10 (e.g. 909) for calibrat- ing PM6690/_5_ & PM6690/_6_ – If no faults are detected, the instrument returns to the normal measurement mode. DC -50 V to +50 V (e.g. 5500A) for...
Page 13 KEY(S) DISPLAY NOTES PARAMETER VALUE/SETTING STANDBY Red standby LED On Input A & B (Key common to ON) Trigger Level AUTO Backlight On Red standby LED Off Trigger Slope (Key common to STANDBY) Impedance 1 MW INPUT A Input A: Menu for setting Slope, Attenuator Coupling, Impedance...
Page 14: Short Form Specification Test
– Repeat the measurement with inverted polarity. Short Form Specification – Press and select INPUT A Test – Press EXIT/OK Sensitivity and Frequency Range CAUTION: Before the next step, make sure the input impedance is still 1 MW. Apply- – Recall the DEFAULT settings. ing more than 12 V without proper current –...
Page 15 Suitable – Repeat the trigger level settings above to verify the three Reference trigger indicator modes for Input B. Standard 10.00000000 MHz ± 150 Hz (PM6690/_1_) Input Controls OCXO 10.00000000 MHz ± 1 Hz – Recall the DEFAULT settings. (PM6690/_5_) –...
Page 16: Rear Inputs/Outputs
Selected Function Action Display Rear Inputs/Outputs 10 MHz 2) FREQ A 10 MHz OUT 10 MHz 2) FREQ B – Connect an oscilloscope to the 10 MHz output on the - - - - - - - - - - - - - - 3) rear of the counter.
Page 17: Check Of Hold Off Function
– Check that the timer/counter performs the correct mea- RF Options surement by displaying the result as shown under the “Display” column in Table 2-8. Input C Check – Select function via MEAS FUNC To verify the specification of the different RF prescalers (Input C), use the following basic test setup: –...
Page 18 This page is intentionally left blank. 2-8 Performance Check, RF Options...
Page 19: Disassembly
Chapter 3 Disassembly...
Page 20: Removing The Cover
RF Input 20 GHz Figure 3-1 Terms used in this manual. The PM6690 can be equipped with a number of options and accessories. Built-in timebase and prescaler options can be identified by pressing USER OPT ® About on the front panel.
Page 21: Fan
– Pull the interior unit out of the cover. – Disconnect the power cable. – Remove the cover from the counter. See page 3-2. – Remove the four screws, nuts and washers that fix the fan to the rear panel. –...
Page 22: Ocxo Options
– Reconnect the RF input cable. OCXO Options – Disconnect the power cable. – Remove the cover from the counter. See page 3-2. – Turn the instrument upside down. – Locate the five solder joints and remove the OCXO with conventional desoldering technique for plated-through holes.
Page 23: Circuit Descriptions
Chapter 4 Circuit Descriptions...
Page 24 This page is intentionally left blank.
Page 25: Version A
Version A The descriptions in this section apply to instru- ments having a Triscend microprocessor. See General Information on page III for details on relevant serial numbers etc. Version A 4-3...
Page 26: Block Diagram Description
Block Diagram Description General Block Diagram The PM6690 Timer/Counter consists of three main units: Figure 4-1 contains a block diagram of the electrical functions of the counter. They are divided among the main circuit board, – Front unit the display board, the rear panel and the optional prescaler –...
Page 27 LINE SEPARATE BOARD ON/OFF AC/DC -15 V +15 V +5 V MEMORY +15 V STDBY -FLASH 8 MB +12 V -SDRAM 32 MB +5 V POWER -12 V SUPPLY -5.2 V KEYBOARD -2.1 V +3.3 V +2.5 V +1.8 V DISPLAY BOARD MICROPROCESSOR RESET...
Page 28: Hardware Functional Description
Hardware Functional Description Front Unit output signals are LVPECL (+2.4 V and +1.2 V approxi- mately) and fed to the measuring logic. The front unit consists of a front piece in molded aluminum, a For a block diagram of the input amplifiers, see Figure 4-2. silicon rubber keypad with conducting contact surfaces, a graphic LCD with LED backlight, and a PCB having etched Impedance Selector...
Page 29 Crossover Switch from an optional prescaler. It has PECL levels (+4.1 V and +3.4 V) that are converted to LVTTL levels (+2.4 V and 0 V). This stage uses relays to direct the signal to the two compara- tors. The following combinations are possible: Oscillator Circuits •...
Page 30 The 10 MHz reference signal is multiplied in a PLL to An external control input BNC is located on the rear panel. A 100 MHz. The 100 MHz signal is used in the measuring logic signal applied to this connector can be used for controlling the as a reference.
Page 31 – Power supply inlet including EMI filter INPUT A INPUT B INPUT C GPIB IEEE 488 10 MHz OUT EXT REF EXT ARM 1Vrms IN 50W FREQ INPUT INPUT E 191125 Figure 4-3 Rear panel, PM6690. Hardware Functional Description 4-9...
Page 32: Test Routines
– Optional main inputs replacing corresponding front panel inputs OUTPUTS: – Internal reference 10 MHz (BNC) Prescaler Circuit Board There are several different optional prescalers available with different frequency ranges. The prescaler is located on a sepa- rate circuit board that is connected to the main circuit board with a PCB connector.
Page 33: Version B
Version B The descriptions in this section apply to instru- ments having a Sharp microprocessor. See General Information on page III for details on relevant serial numbers etc. Version B 4-11...
Page 34: Block Diagram Description
Block Diagram Description General Block Diagram The PM6690 Timer/Counter consists of three main units: Figure 4-7 contains a block diagram of the electrical functions of the counter. They are divided among the main circuit board, – Front unit the display board, the rear panel and the optional prescaler –...
Page 35 LINE SEPARATE BOARD ON/OFF AC/DC -15 V +15 V +5 V MEMORY +15 V STDBY -FLASH 8 MB +12 V -SDRAM 32 MB +5 V POWER -12 V SUPPLY -5.2 V KEYBOARD -2.1 V +3.3 V +1.8 V DISPLAY BOARD MICROPROCESSOR RESET ARM 7...
Page 36: Hardware Functional Description
Hardware Functional Description Front Unit output signals are LVPECL (+2.4 V and +1.2 V approxi- mately) and fed to the measuring logic. The front unit consists of a front piece in molded aluminum, a For a block diagram of the input amplifiers, see Figure 4-8. silicon rubber keypad with conducting contact surfaces, a graphic LCD with LED backlight, and a PCB having etched Impedance Selector...
Page 37 Crossover Switch from an optional prescaler. It has PECL levels (+4.1 V and +3.4 V) that are converted to LVTTL levels (+2.4 V and 0 V). This stage uses relays to direct the signal to the two compara- tors. The following combinations are possible: Oscillator Circuits •...
Page 38 The 10 MHz reference signal is multiplied in a PLL to start of a measurement, for instance. A comparator converts 100 MHz. The 100 MHz signal is used in the measuring logic the analog input signal to a logic signal. as a reference.
Page 39 – Optional main inputs replacing corresponding front standby mode panel inputs INPUT A INPUT B INPUT C GPIB IEEE 488 10 MHz OUT EXT REF EXT ARM 1Vrms IN 50W FREQ INPUT INPUT E 191125 Figure 4-9 Rear panel, PM6690. Hardware Functional Description 4-17...
Page 40: Test Routines
OUTPUTS: – Internal reference 10 MHz (BNC) Prescaler Circuit Board There are several different optional prescalers available with different frequency ranges. The prescaler is located on a sepa- rate circuit board that is connected to the main circuit board with a PCB connector. A typical prescaler consists of a limiter, an amplifier, a fre- quency divider, and a detector.
Page 41: Corrective & Preventive Maintenance
Chapter 5 Corrective & Preventive Maintenance...
Page 42: Introduction
to the same bus. Firmware upgrade over USB works Introduction with firmware version V1.07 or above installed in the instrument. This chapter contains information about measures to be taken – Send *IDN? to the instrument and watch the response. for keeping the instrument in operative condition, or in other If the ID string is OK you can exit the communication words, what you can do to maintain the measurement accu- program and start the upgrading procedure.
Page 43: Utility Program
Running the Application After installation you can start the utility application by run- ning the program PM6690 Utility.exe from the chosen direc- tory. Refer to the readme.txt file for closer information on top- ics not covered by the application user interface.
Page 44 This page is intentionally left blank. 5-4 Other Important Information...
Page 45: Repair
Chapter 6 Repair...
Page 46 This page is intentionally left blank.
Page 47: Version A
Version A The descriptions in this section apply to instru- ments having a Triscend microprocessor. See General Information on page III for details on relevant serial numbers etc. Version A 6-3...
Page 48: Troubleshooting
Troubleshooting General do the checks in Chapter 2, Performance Check. Recalibrate if required by following the adjustment instructions in Chapter The '90' is a highly integrated Timer/Counter in which a dedi- 7, Calibration Adjustments. cated FPGA counter circuit handles the signal processing, and a microcontroller does the postprocessing and supervising Logic Levels jobs.
Page 49 the ON/OFF circuitry and the optional oven oscillator are It can be difficult to measure the resistance in the supply con- powered. nector J17 on the main circuit board, because charges are kept by capacitors some time after line power is removed. Remove The AC/DC module should not be repaired.
Page 50 On connection of line power, R478 and C389 keep the TP14: +3.3 VD (from +5 VU) RESETN input of the flip-flop U29 low. This sets the QN out- TP1: +2.5 V (from +5 VU) put of U29 high. Via Q47 (output signal low) and Q58 (output TP2: +1.8 V (from +5 VU) signal high) the secondary power supply will be set in ON Some voltages derived directly from the AC/DC module are...
Page 51 Fan Control The fan is connected to +15 VU over a speed control circuit. It is only ON if a control signal from the processor is present. The first 8 minutes after power-up the fan will run at a fixed speed, fed with +8.3 V.
Page 52: Input Amplifiers
+5VU ON L ON H OFF H OFF L +5VU R449 R449 ON H R593 R593 OFF L R584 R584 R453 R453 OFFCTRL U29A U29A R592 R592 OF F R466 R466 BC847B BC847B BC847B BC847B R472 R472 LVC74A LVC74A ONCTRL R478 R478 C389...
Page 53 Figure 6-7 Test points for troubleshooting the input amplifiers. Figure 6-8 Oscillogram showing the signal at the interconnection of R140 (R212) and R141 (R213). Troubleshooting 6-9...
Page 54 Figure 6-9 Oscillogram showing the signal at the interconnection of R156 (R229) and C109 (C140). Figure 6-10 Oscillogram showing the signal at U3:9 (U3:13). 6-10 Troubleshooting...
Page 55 Figure 6-11 Oscillogram showing the signal at U1:2 (U2:2). Figure 6-12 Oscillogram showing the signal at X6, Period Single A. Troubleshooting 6-11...
Page 56: Timebase Reference Circuits
Figure 6-13 Oscillogram showing the signal at X7, Period Single B. nal oscillator. Check for correct signals at U4:6 for the stan- Timebase Reference dard oscillator, at U4:8 for ther oven oscillator and at U33:3 Circuits for the external reference. Check also that the selected timebase reference is present at the internal reference output BNC connector on the rear panel.
Page 57 X17. The oven oscillator should be powered also in standby 100 MHz Multiplier mode. See Figure 6-14 and Figure 6-16. The oven oscillator outputs a 10 MHz signal if powered. It 100 MHz is used in the measuring logic, mainly as a reference should be 1.3 V measured at R282.
Page 58 Figure 6-16 Important locations in the internal timebase reference circuits. Figure 6-17 Important locations in the external timebase reference circuits. 6-14 Troubleshooting...
Page 59: Prescalers
locked, and the VCO will go to one of the extremes. The typi- Microprocessor & Memories cal range of the VCO is 95 to 105 MHz, thus giving an error of typically 5 % in the measuring results. Startup Process Check the loop voltage (DC) at R272.
Page 60 R492 Figure 6-18 Important locations on PCB 1 during startup. processor. See Figure 6-22. The loading starts when PROGN interrupt to the processor. Check at J13:9; low is interrupt. is set low. The FPGA responds with a negative pulse on The processor then scans the keys via the I C bus to find the INITN and setting DONE low.
Page 61 Figure 6-20 Microprocessor, memories - startup. Troubleshooting 6-17...
Page 62 OSC 32 MHz µP CLK 30 MHz FLASH PROM CEØ SDRAM CEØ RESETN Figure 6-21 Startup timing - processor, memories, fan. PROGN INITN DONE CLOCK RESETN Figure 6-22 FPGA loading. 6-18 Troubleshooting...
Page 63 RESETN Figure 6-23 Fan startup - extended timescale. ON via I CONTRAST RESETN Figure 6-24 LCD control signals, ocillogram #1. Figure 6-25 LCD control signals, oscillogram #2. Troubleshooting 6-19...
Page 64 Figure 6-26 LCD control signals, oscillogram #3. Figure 6-27 LCD control signals, oscillogram #4. Figure 6-28 LCD control signals, oscillogram #5. 6-20 Troubleshooting...
Page 65: Microprocessor Bus & Interfaces
RESETN Figure 6-29 LCD control signals, oscillogram #6. Chip Selects and wrn and rdn signals. It connects the proces- sor to the FPGA, the GPIB and the USB. See Figure 6-34. The FPGA connection has 16 data bits, 5 address bits, chip select, wrn and rdn.
Page 66 Since both interfaces consist of only one IC each, trouble- The addressed slave accepts by keeping the SDA line low shooting is fairly simple. Check that the oscillator (40 MHz or while the acknowledge bit (ACKN in ) is sent by the micro- 6 MHz) is running.
Page 67 Figure 6-34 Microprocessor bus and interfaces. Troubleshooting 6-23...
Page 68 C416 Figure 6-35 Important locations for the microprocessor and its buses and interfaces. DØ AØ DØ AØ Figure 6-37 Figure 6-36 Microprocessor bus - FPGA timing - Power On. Microprocessor bus - FPGA timing - Single Pe- riod. 6-24 Troubleshooting...
Page 69 GPIB DIR DØ DØ AØ AØ Figure 6-38 Figure 6-39 Microprocessor bus - USB timing - Power On. Microprocessor bus - GPIB timing - Power On. START CONTINUOUS 30 MHz INTERPOL FIFOCLK EMPTY FIFOALERT FIFOWR FIFOWR Figure 6-41 Figure 6-40 FIFO timing #2.
Page 70 DATA DATA CLOCK CLOCK Figure 6-42 Figure 6-43 SPI bus activity - oven. SPI bus activity - PLL. CLOCK DATA CLOCK DATA Figure 6-44 Figure 6-45 SPI bus activity - PLL - first transfer close-up. SPI bus activity - trglvl. 6-26 Troubleshooting...
Page 71: Measuring Logic
NORM. TEMP TEMP Figure 6-46 Figure 6-47 C bus activity - reading the temperature. C bus activity - depressing the EXIT key. ferential input) on the FPGA U11.The trigger indicator LED A on the front panel should blink. The gate indicator on the front panel should also blink and the display should show the Measuring Logic measurement result.
Page 72 pin 8 of the ADCs (U23, U22, U21, U20) should be at least 0.2 V above the lower limit and that the highest voltage pulse on any pin 8 of the ADCs should be at least 0.3 V below the upper limit.
Page 73 U21:8 ERRP, R416 U23:8 U23:8 Figure 6-50 Figure 6-52 ADC 1061 behavior. Time A-A, 10 MHz in. Close-up of error pulse and S/H output. pin 2 S/H, pin 3 pin 4 pin 5 RES, R414 ERRP, R416 U23:8 Figure 6-51 Different signals around an ADC.
Page 74 Figure 6-53 Measuring logic, block diagram. 6-30 Troubleshooting...
Page 75: Version B
Version B The descriptions in this section apply to instru- ments having a Sharp microprocessor. See General Information on page III for details on relevant serial numbers etc. Version B 6-31...
Page 76: Troubleshooting
Troubleshooting General do the checks in Chapter 2, Performance Check. Recalibrate if required by following the adjustment instructions in Chapter The '90' is a highly integrated Timer/Counter in which a dedi- 7, Calibration Adjustments. cated FPGA counter circuit handles the signal processing, and a microcontroller does the postprocessing and supervising Logic Levels jobs.
Page 77 the ON/OFF circuitry and the optional oven oscillator are It can be difficult to measure the resistance in the supply con- powered. nector J17 on the main circuit board, because charges are kept by capacitors some time after line power is removed. Remove The AC/DC module should not be repaired.
Page 78 On connection of line power, R478 and C389 keep the X14: +3.3 VD (from +5 VU) RESETN input of the flip-flop U29 low. This sets the QN out- X2: +1.8 V (from +5 VU) put of U29 high. Via Q47 (output signal low) and Q58 (output Some voltages derived directly from the AC/DC module are signal high) the secondary power supply will be set in ON used as secondary supply voltages without further regulation,...
Page 79 Fan Control The fan is connected to +15 VU over a speed control circuit. It is only ON if a control signal from the processor is present. The first 8 minutes after power-up the fan will run at a fixed speed, fed with +8.3 V.
Page 80: Input Amplifiers
+5VU ON L ON H OFF H OFF L +5VU R449 R449 ON H R593 R593 OFF L R584 R584 R453 R453 OFFCTRL U29A U29A R592 R592 OF F R466 R466 BC847B BC847B BC847B BC847B R472 R472 LVC74A LVC74A ONCTRL R478 R478 C389...
Page 81 Figure 6-60 Test points for troubleshooting the input amplifiers. Figure 6-61 Oscillogram showing the signal at the interconnection of R140 (R212) and R141 (R213). Troubleshooting 6-37...
Page 82 Figure 6-62 Oscillogram showing the signal at the interconnection of R156 (R229) and C109 (C140). Figure 6-63 Oscillogram showing the signal at U3:9 (U3:13). 6-38 Troubleshooting...
Page 83 Figure 6-64 Oscillogram showing the signal at U1:2 (U2:2). Figure 6-65 Oscillogram showing the signal at X6, Period Single A. Troubleshooting 6-39...
Page 84: Timebase Reference Circuits
Figure 6-66 Oscillogram showing the signal at X7, Period Single B. the external reference. Check also that the selected timebase Timebase Reference reference is present at the internal reference output BNC con- Circuits nector on the rear panel. The measurement reference is either a 10 MHz signal from an Oven Oscillator internal oven-controlled crystal oscillator on the main circuit See Figure 6-68 and Figure 6-69.
Page 85 must be replaced if the normal control voltage range cannot 100 MHz Multiplier make the oscillator output 10.000000 MHz. See Figure 6-67 and Figure 6-69. As a last resort to exclude external causes of malfunction, 100 MHz is used in the measuring logic, mainly as a reference desolder the oven oscillator from the main circuit board.
Page 86 Figure 6-69 Important locations in the internal timebase reference circuits. Figure 6-70 Important locations in the external timebase reference circuits. 6-42 Troubleshooting...
Page 87: Prescaler
locked, and the VCO will go to one of the extremes. The typi- Microprocessor & Memories cal range of the VCO is 95 to 105 MHz, thus giving an error of typically 5 % in the measuring results. Startup Process Check the loop voltage (DC) at R272.
Page 88 R358 Figure 6-71 Important locations on PCB 1 during startup. voltages. The range is 14.9 V to 17.5 V measured at X1 on the bration results to new factory calibrations. The serial number and the oscillator option must also be pro- display board.
Page 89 Figure 6-73 Microprocessor, memories - startup. Troubleshooting 6-45...
Page 90 µ P CLOCK FLASH PROM CE SDRAM CE OSC 11 MHz RESN Figure 6-74 Startup timing - processor, memories, fan. PROGN INITN DONE CCLK RESN Figure 6-75 FPGA loading. 6-46 Troubleshooting...
Page 91 Figure 6-76 Startup indicator test points. CONTRAST RESN Figure 6-77 LCD control signals, ocillogram #1. Figure 6-78 LCD control signals, oscillogram #2. Troubleshooting 6-47...
Page 92 Figure 6-79 LCD control signals, oscillogram #3. Figure 6-80 LCD control signals, oscillogram #4. Figure 6-81 LCD control signals, oscillogram #5. 6-48 Troubleshooting...
Page 93: Microprocessor Bus & Interfaces
RESN Figure 6-83 LCD control signals, oscillogram #6. may appear some extra interrupts. This is not an error condi- tion. Microprocessor Bus & Interfaces The microprocessor bus is divided into two parts with buffers. The inner part consists of the Flash PROM and the SDRAMs. Buffers isolate the inner part from long lines in order to make the SDRAM work safely.
Page 94 The connection to the USB has 16 data bits, 1 address bit, chip The SDA and SCL are high at standby. All ICs connected to select, wrn and rdn. An interrupt signal from the USB IC is the bus can sink SDA to low as they are interconnected via connected to the processor.
Page 95 Figure 6-87 Microprocessor bus and interfaces. Troubleshooting 6-51...
Page 96 C416 Figure 6-88 Important locations for the microprocessor and its buses and interfaces. Figure 6-89 Microprocessor bus - FPGA timing - Single Pe- riod - Hold, after Restart. 6-52 Troubleshooting...
Page 97 GPIB DIR AØ AØ Figure 6-90 Figure 6-91 Microprocessor bus - USB timing - Power On. Microprocessor bus - GPIB timing - Power On. START INTERPOL EMPTY ALERT CS FPGA Figure 6-92 FIFO timing - Block:5, Single Period, 10 MHz. Troubleshooting 6-53...
Page 98 DATA DATA CLOCK CLOCK Figure 6-93 Figure 6-94 SPI bus activity - oven - directly after power-up. SPI bus activity - PLL - directly after power-up. CLOCK DATA CLOCK DATA Figure 6-95 Figure 6-96 SPI bus activity - PLL - first transfer close-up. SPI bus activity - trglvl.
Page 99: Measuring Logic
HIGH TEMP TEMP Figure 6-97 Figure 6-98 C bus activity - reading the temperature. C bus activity - depressing the EXIT key. puts. C, the prescaler input, is a single-ended LVTTL input. The measuring logic also provides three LEDs on the front The I C Bus in the ‘90’...
Page 100 Move the 10 MHz sinewave signal back to input A. Change the measurement function to Period Single A. Now the S/R flip-flop should not be used, check the control signal at R623, it should be -1.6 V (on is -1.0 V). Select statistics. The std de- U20:8 viation should be less than 100 ps.
Page 101 pin 2 ERRP, R403 S/H, pin 3 U22:8 pin 4 Figure 6-102 Close-up of error pulse and S/H output. pin 5 RES, R414 RE SN ERRP, R416 3.3 V U23:8 Figure 6-103 Power-up & Reset. Figure 6-101 Different signals around an ADC. Troubleshooting 6-57...
Page 102 Figure 6-104 Measuring logic, block diagram. 6-58 Troubleshooting...
Page 103: Safety Inspection And Test After Repair
Safety Inspection and Test After Repair General Directives Check the Protective Ground Connection Visually check the correct connection and condition and mea- After repair in the primary circuits, make sure that you have sure the resistance between the protective lead at the plug and not reduced the creepage distances and clearances.
Page 104 This page is intentionally left blank. 6-60 Safety Inspection and Test After Repair...
Page 105: Calibration Adjustments
Chapter 7 Calibration Adjustments...
Page 106: General Principles
Measure the deviation and record the value. Use a ref- erence source whose uncertainty is at least an order of magnitude less than that of the DUT. Model Option Standard PM6690/_5_ PM6690/_6_ Timebase type UCXO OCXO OCXO Total uncertainty, for operating temperature 0°C to 50°C,...
Page 107: The Calibration Submenu
Continuous operation is also important for Certain internal delays are measured in order to correct the re- optimum stability. Option PM6690/_6_, for example, has an sults of real measurements. This is done without applying ex- aging/24h that is 1x10 when operating continuously.
Page 108 DUT for a reliable calibration result. DUT Option Reference Oscillator Standard PM6690/_5_ – Press and select one of the possible frequen- Calib Freq PM6690/_5_...
Page 109: Voltage Reference
Timebase Calibration via the GPIB or the USB +50 V, +20 V, +5 V, +2 V, +0.5 V, 0 V, -0.5 V, -2 V, -5 V, -20 V, -50 V The frequency calibration can also be performed by sending – Key in the following sequence on the DUT. commands over one of the interface buses.
Page 110: Calibration Subsystem Command Reference
Calibration Subsystem Command Reference :CALibration DELays :INITialize :STARt :STORe :ROSCillator <Numeric Value> :FREQuency <Boolean> :AUTO :INITialize :LOAD :FACTory :USER :STARt <YYYYMMDD> :STORe :VOLTage :INITialize :INPut1 <Numeric Value> :VAL :INPut2 <Numeric Value> :VAL :LOAD :FACTory :USER <YYYYMMDD> :STORe 7-6 Voltage Reference...
Page 111 :CALibration :DELays :INITialize Calibration of Internal Delays Initializes the calibration process. :CALibration :DELays :STARt Calibration of Internal Delays Starts the calibration process. :CALibration :DELays :STORe Calibration of Internal Delays Ends the calibration process and stores the calibration factors. :CALibration :ROSCillator :FREQuency 8<Numeric value>...
Page 112 :CALibration :ROSCillator :FREQuency :AUTO 8<Boolean> Calibration of Reference Oscillator Switches the AUTO mode ON/OFF for the reference frequency calibration. If ON, the timer/counter measures the applied reference frequency before the start of the calibration process and adjusts the calculation algorithm ac- cordingly.
Page 113 :CALibration :ROSCillator :STARt Start Calibration Starts the calibration process after an external reference source has been connected to Input A. :CALibration :ROSCillator :STORe 8<YYYYMMDD> Store User Calibration Ends the calibration process and stores the calibration factors using the date code YYYYMMDD, that is year (4 digits), month (2 digits), and day (2 digits).
Page 114 :CALibration :VOLTage :LOAD :FACTory Restore Factory Calibration Recalls the calibration factors stored by the factory before delivery or after service. :CALibration :VOLTage :LOAD :USER Restore User Calibration Recalls the calibration factors last stored by the user. :CALibration :VOLTage :STORe 8<YYYYMMDD> Store User Calibration Ends the calibration process and stores the calibration factors using the date code YYYYMMDD, that is year (4 digits), month (2 digits), and day (2 digits).
Page 115: Adjustments
Adjustments Preparations WARNING: Live parts and accessible termi- Before beginning the adjustments, power up the instrument nals which can be dangerous to life are after removing the cover (see Chapter 3) and leave it on for at always exposed inside the unit when it is least 60 minutes to let it reach normal operating temperature.
Page 116: Input Amplifiers
Input Amplifiers Overcompensation Check the power supply voltages according to the instructions Correct compensation on page 7-13 before proceeding to the next step. Undercompensation Input signal All adjustments on the input amplifiers must be made in the specified order. The input amplifiers are enclosed in an RF shield consisting of a metal lid that is soldered to two of the shield clips on the main circuit board.
Page 117: Power Supply
Adjustment Adjustment – Connect the probe tip to the center hole of J7.The sur- – Connect the DMM to test point X9 and ground (metal rounding holes are suitable ground connections. See Fig- shield lid over input amplifiers). See Figure 6-4 and ure 7-2.
Page 118: Internal Reference Oscillators
Internal Reference Oscillators Adjustment of the different timebase oscillators is described under Calibration earlier in this chapter. RF Input 3 GHz Note: The 8 GHz prescaler can not be adjusted. Setup – Do as described under Preparations above. ® – Select default settings by keying in USER OPT ®...
Page 119: Replacement Parts
Chapter 8 Replacement Parts...
Page 120: Introduction
In addition to standard electronic components, the following special components are used: Standard Parts – Components that are manufactured or selected by Fluke to Electrical and mechanical replacement parts can be obtained meet specific performance requirements. through your local service organization or representative. How- –...
Page 121: Mechanical Parts
Screw MRT 3x6 482250211658 Keypad 403110065980 Screw MFT-TT 4x12 532250213553 Front unit board, complete 403110066160 Power Module 403110066170 Front overlay PM6690 403110066060 Screw MRT-TT 4x16 532250213552 Washer 3,2 ST FZ 252261024004 Cable assembly, power supply 403110066150 Cover assembly 403110066440 Distance nut M3x14...
Page 122 Figure 8-2 Exploded view of chassis. Green/Yellow Blue Brown Figure 8-3 Rear panel. 8-4 Replacement Parts, Mechanical Parts...
Page 123: Main Board, Version A
Pos Description Part Number Pos Description Part Number Main board complete 403110066470 C155 CAPACITOR 2.20 µF 20%6.3V 3.2X1.6 MOLD 532212410685 OCXO (PM6690/_5_) 403110065330 C156 CAPACITOR 10nF 20% 50V X7R 0805 222286148103 OCXO (PM6690/_6_) 403110065340 C157 CAPACITOR 10nF 20% 50V X7R 0805...
Page 124 Pos Description Part Number Pos Description Part Number C214 CAPACITOR 10nF 20% 50V X7R 0805 222286148103 C276 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 C215 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 C278 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 C216 CAPACITOR 10nF 20% 50V X7R 0805 222286148103...
Page 125 Pos Description Part Number Pos Description Part Number C338 CAPACITOR 100pF 5% 50V NP0 0805 532212232531 C411 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 C339 CAPACITOR 15 µF 20%6.3V 6.0X3.2 MOLD 532212411418 C412 CAPACITOR 10nF 20% 50V X7R 0805 222286148103 C340 CAPACITOR 100nF 20% 25V X7R 0805 532212613638...
Page 126 Pos Description Part Number Pos Description Part Number C492 CAPACITOR 22µF 20% 35V 0605 SMD 222215360229 CONNECTOR 6POS 39-28-1065 242202508091 C493 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 CONNECTOR 4POL USB PCB 242203300291 C494 CAPACITOR 10nF 20% 50V X7R 0805 222286148103 CONNECTOR 24 POL 57LE-20240-77OOD35G 242202504832...
Page 127 Pos Description Part Number Pos Description Part Number FILTER-EMI BLM21A102SPT Z=1KOhm 0.2A 242254943133 SHIELD-CLIP SMD 242201520096 R=0.6Ohm TRANSISTOR BF513 .03A20V SOT23 482213060686 FILTER-EMI BLM21A102SPT Z=1KOhm 0.2A 242254943133 TRANSI-HF N SMD BFR93A 35mA 12V SOT23 532213060705 R=0.6Ohm TRANSISTOR 25 MA BFR92A 20V SOT23 532213060647 FILTER-EMI BLM21A102SPT Z=1KOhm 0.2A...
Page 128 Pos Description Part Number Pos Description Part Number RESISTOR 2.2 kOhm 1% 0.1W 100PPM 0805 403100222020 R192 RESISTOR 000 Ohm 0.1W 100PPM 0805 403100200000 RESISTOR 10 kOhm 1% 0.1W 100PPM 0805 532211712499 R193 RESISTOR 330 Ohm 1% 0.1W 100PPM 0805 532211712508 RESISTOR 10 kOhm 1% 0.1W 100PPM 0805 532211712499...
Page 129 Pos Description Part Number Pos Description Part Number R256 RESISTOR 220 Ohm 1% 0.1W 100PPM 0805 403100222010 R326 RESISTOR 100 Ohm 1% 0.1W 100PPM 0805 532211712497 R257 RESISTOR 1 kOhm 1% 0.1W 100PPM 0805 532211712498 R327 RESISTOR 47 Ohm 1% 0.1W 100PPM 0805 532211712505 R258 RESISTOR 120 kOhm 1% .125W 100PPM 1206...
Page 130 Pos Description Part Number Pos Description Part Number R395 RESISTOR 33 kOhm 1% 0.1W 100PPM 0805 403100233030 R469 RESISTOR 10.0 Ohm 1% 0.125W 100PPM 1206 482205110109 R396 RESISTOR 4.7 kOhm 1% 0.1W 100PPM 0805 403100247020 R470 RESISTOR 10.0 Ohm 1% 0.125W 100PPM 1206 482205110109 R397 RESISTOR 47 Ohm 1% 0.1W 100PPM 0805...
Page 131 Pos Description Part Number Pos Description Part Number R533 RESISTOR 100 Ohm 1% 0.125W 100PPM 1206 482205151001 R602 RESISTOR 10.0 Ohm 1% 0.125W 100PPM 1206 482205110109 R534 RESISTOR 22 Ohm 1% 0.1W 100PPM 0805 532211712507 R603 RESISTOR 10.0 Ohm 1% 0.125W 100PPM 1206 482205110109 R535 RESISTOR 22 Ohm 1% 0.1W 100PPM 0805...
Page 132: Front Unit
Pos Description Part Number Pos Description Part Number IC-OPAMP OPA277 932214746682 IC-CMOS 74HCT126D SMD SO14 933757050701 IC-OPAMP OPA277 932214746682 IC-OP AMP KM4100IT5 SOT23-5 260MHz 403106000002 IC-OPAMP LMC6081 932220497682 IC-OP AMP KM4100IT5 SOT23-5 260MHz 403106000002 IC-OMV ADC 10BIT ADC1061C1WM SO20 932218755682 IC-OP AMP KM4100IT5 SOT23-5 260MHz 403106000002 IC-OMV ADC 10BIT ADC1061C1WM SO20...
Page 133 Pos. Description Part number Display board complete. 403110066160 CAPACITOR 100nF 20% 25V X7R 0805 222291016749 CAPACITOR 100nF 20% 25V X7R 0805 222291016749 CAPACITOR 100nF 20% 25V X7R 0805 222291016749 CAPACITOR 100nF 20% 25V X7R 0805 222291016749 CAPACITOR 100nF 20% 25V X7R 0805 222291016749 CAPACITOR 100nF 20% 25V X7R 0805 222291016749...
Page 134: Main Board, Version B
Main Board, Version B Pos Description Part Number Pos Description Part Number OSCILLATOR 10MHZ OCXO P/N 738Y4084 403110061800 C154 CAPACITOR 22nF 10% 200V X7R 1206 532212614081 CRYSTAL 10MHz HC-49U/13 532224282118 C155 CAPACITOR 2.20 µF 20%6.3V 3.2X1.6 MOLD 532212410685 CRYSTAL 6MHz HC49/USM SMD 403110056520 C156 CAPACITOR 10nF 20% 50V X7R 0805...
Page 135 Pos Description Part Number Pos Description Part Number C212 CAPACITOR 10nF 20% 50V X7R 0805 532212234098 C281 CAPACITOR 100nF 10% 16V X7R 0603 403102030104 C213 CAPACITOR 6.80 µF 20% 16V 6.0X3.2 MOLD 532212410687 C282 CAPACITOR 100nF 10% 16V X7R 0603 403102030104 C214 CAPACITOR 10nF 20% 50V X7R 0805...
Page 136 Pos Description Part Number Pos Description Part Number C341 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 C405 CAPACITOR 10nF 20% 50V X7R 0805 532212234098 C342 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 C406 CAPACITOR 4.7µF 20% 35V 0405 SMD 222215360478 C343 CAPACITOR 1nF 20% 50V X7R 0805 532212234123...
Page 137 Pos Description Part Number Pos Description Part Number C476 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 C562 CAPACITOR 100µF 6.3V 202202900655 C477 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 C563 CAPACITOR 100µF 6.3V 202202900655 C478 CAPACITOR 100nF 20% 25V X7R 0805 532212613638 C564 CAPACITOR 100µF 6.3V...
Page 138 Pos Description Part Number Pos Description Part Number CONNECTOR 6POS 39-28-1065 242202508091 FILTER-EMI BLM21A102SPT Z=1Kohm 0.2A 242254943133 R=0.6ohm CONNECTOR 4POL USB PCB 242203300291 FILTER-EMI BLM21A102SPT Z=1Kohm 0.2A 242254943133 CONNECTOR 24 POL 57LE-20240-77OOD35G 532226760148 R=0.6ohm CONNECTOR HEADER 2POS SMD AMP 403110571100 FILTER-EMI BLM21A102SPT Z=1Kohm 0.2A 242254943133 6-176125-2...
Page 139 Pos Description Part Number Pos Description Part Number SHIELD-CLIP SMD 242201520096 RESISTOR 4.7 KOHM 1% 0.1W 100PPM 0805 403100247020 SHIELD-CLIP SMD 242201520096 RESISTOR 2.2 KOHM 1% 0.1W 100PPM 0805 403100222020 SHIELD-CLIP SMD 242201520096 RESISTOR 10kohm 1% 0.1W 100PPM 0805 532211712499 TRANSISTOR BF513 .03A20V SOT23 482213060686 RESISTOR 10kohm 1% 0.1W 100PPM 0805...
Page 140 Pos Description Part Number Pos Description Part Number R192 RESISTOR 000 ohm 0.1W 100PPM 0805 403100200000 R252 RESISTOR 1kohm 1% 0.1W 100PPM 0805 532211712498 R193 RESISTOR 330 OHM 1% 0.1W 100PPM 0805 403100233010 R253 RESISTOR 150 ohm 1% 0.125W 100PPM 1206 482205151501 R194 RESISTOR 27 ohm 1% 0.1W 100PPM 0805...
Page 141 Pos Description Part Number Pos Description Part Number R323 RESISTOR 100 ohm 1% 0.1W 100PPM 0805 532211712497 R400 RESISTOR 47 KOHM 1% 0.1W 100PPM 0805 403100247030 R324 RESISTOR 100 ohm 1% 0.1W 100PPM 0805 532211712497 R402 RESISTOR 47 ohm 1% 0.1W 100PPM 0805 532211712505 R325 RESISTOR 47 ohm 1% 0.1W 100PPM 0805...
Page 142 Pos Description Part Number Pos Description Part Number R474 RESISTOR 10.0 ohm 1% 0.125W 100PPM 1206 482205110109 R537 RESISTOR 10.0 ohm 1% 0.125W 100PPM 1206 482205110109 R475 RESISTOR 10.0 ohm 1% 0.125W 100PPM 1206 482205110109 R538 RESISTOR 120 ohm 1% 0.125W 100PPM 1206 482205110121 R476 RESISTOR 10.0 ohm 1% 0.125W 100PPM 1206...
Page 143 Pos Description Part Number Pos Description Part Number R605 RESISTOR 10.0 ohm 1% 0.125W 100PPM 1206 482205110109 R669 RESISTOR 22 ohm 1% 0.1W 100PPM 0805 532211712507 R606 RESISTOR 100 ohm 1% 0.125W 100PPM 1206 482205151001 IC-OPAMP LMC6081 932220497682 R607 RESISTOR 100 ohm 1% 0.125W 100PPM 1206 482205151001 IC-FPGA 932220399682...
Page 144: Parts Unique To Version A
Pos Description Part Number Pos Description Part Number IC-OPAMP OPA277 932214746682 IC-CMOS 74LVC162245ADGG TSSOP48 403106000010 IC-OP AMP LM358 x2 SMD SO8 933965740685 IC-CMOS 74LVC162245ADGG TSSOP48 403106000010 IC-OP AMP LM358 x2 SMD SO8 482220960175 IC-CMOS 74LVC162245ADGG TSSOP48 403106000010 IC-ANALOG-PLL 200MHz ADF4001BRU 932220404682 IC-CMOS 74LVC08AD SO14 403106000009...
Page 145 + Pos - Pos Part Number R585,R586,R587 403100247010 R523,R628,R635,R636 403100247020 R371 403100247030 C431 403102131590 U117 932220434682 933757050701 Replacement Parts, Parts Common to Version A and Version B 8-27...
Page 146 This page is intentionally left blank. 8-28 Replacement Parts, Parts Common to Version A and Version B...
Page 147: Schematic Diagrams
Chapter 9 Schematic Diagrams...
Page 148: How To Read The Diagrams
Inside the symbol there is sometimes an abbreviated descrip- How to Read the Diagrams tion of the circuit’s function. This chapter contains circuit diagrams and component layout Pin numbers are written outside the symbol and, if the circuit information. is complex, the pin functions are written inside. A small circle on a pin indicates that the input/output inverts Signals the signal.
Page 149: Version A
Version A The descriptions in this section apply to instru- ments having a Triscend microprocessor. See General Information on page III for details on relevant serial numbers etc. Schematic Diagrams 9-3...
Page 150 This page is intentionally left blank. 9-4 Schematic Diagrams...
Page 151 This page is intentionally left blank. Schematic Diagrams 9-5...
Page 152 Main Board, PCB 1, Component Layout 9-6 Schematic Diagrams...
Page 153 Main Schematic MD[0..31] MA[0..21] U15A U15A U16A U16A MD16 I/O0 I/O0 MD17 I/O1 I/O1 MA10 MA10 MD18 I/O2 I/O2 MA11 MA11 MD19 I/O3 I/O3 MA12 MA12 MD20 I/O4 I/O4 MA13 MA13 MD21 I/O5 I/O5 MA14 MA14 MD22 I/O6 I/O6 MA15 MA15 MD23 I/O7...
Page 154 This page is intentionally left blank. 9-8 Schematic Diagrams...
Page 155 CPU, Memories and Parts of the Counter Circuit, PCB 1, sheet 1(7) MD[0..31] MD[0..31] MA[0..21] +3.3VCPU C249 C249 C248 C248 27PF 27PF 27PF 27PF R355 R355 MA[0..21] 32KHZ 32KHZ U14A U14A R356 R356 R357 R357 +3.3VCPU 2.2K 2.2K 2.2K 2.2K U17A U17A R358...
Page 156 This page is intentionally left blank. 9-10 Schematic Diagrams...
Page 157 Input Amplifiers, PCB 1, sheet 2(7) C496 C496 R132 R132 TRG_LVL_A R133 R133 R134 R134 2.5-10PF/250V 2.5-10PF/250V -5.2VAI +5VAI +5VAI C100 C100 C101 C101 C102 C102 C103 C103 100NF 100NF R610 R610 100NF 100NF 100NF 100NF +12VI +5VAI 1.2M 1.2M 3.9pF-500V 3.9pF-500V BAV99...
Page 158 This page is intentionally left blank. 9-12 Schematic Diagrams...
Page 159 Interpolators, PCB 1, sheet 3(7) R[0..3] AD[1..10] +12VINT R505 R505 R481 R481 R484 R484 R485 R485 U20A U20A BLM21A102S BLM21A102S C507 C507 BF513 BF513 R513 R513 R511 R511 R508 R508 R507 R507 C332 C332 C321 C321 6.8u-16V 6.8u-16V R377 R377 100NF 100NF 2.2K...
Page 160 This page is intentionally left blank. 9-14 Schematic Diagrams...
Page 161 Miscellaneous, PCB 1, sheet 4(7) PROGN R564 R564 FILTER_A +5VD C470 C470 R418 R418 2.2K 2.2K R419 R419 BC807-25 BC807-25 OPCLK 1,2,6,7,8 +3.3VD 6.8K 6.8K IMP A PRES CAL ER CONNECT OR BLM21A102S BLM21A102S PREKOD2 +5VD C471 C471 -5.2VA PREKOD1 100NF 100NF PREKOD0...
Page 162 This page is intentionally left blank. 9-16 Schematic Diagrams...
Page 163 Oscillator Circuits, PCB 1, sheet 5(7) SPICLK SPIDATA +3.3V_PLL U47A U47A R269 R269 R270 R270 OVEN OSC ON/OFF LVC1G04 LVC1G04 R271 R271 DATA C168 C168 C169 C169 LOAD PLL R272 R272 R274 R274 3.3K 3.3K C170 C170 R275 R275 +3.3V_U4 100P 100P REFIN...
Page 164 This page is intentionally left blank. 9-18 Schematic Diagrams...
Page 165 Supply Voltages, PCB 1, sheet 6(7) U126 U126 +5VU +3.3VA SENSE SHDN VTAP R482 R482 R483 R483 C396 C396 3.3K 3.3K 3.3K 3.3K C393 C393 C394 C394 100uF-6.3V 100uF-6.3V 100uF-6.3V 100uF-6.3V ERROR LP2951CM LP2951CM R486 R486 -5.2VI -5.2VI +5VU R594 R594 R598 R598...
Page 166 This page is intentionally left blank. 9-20 Schematic Diagrams...
Page 167 Rear Panel, Interfaces and I/O, PCB 1, sheet 7/7 +3.3VEC EXTCTRL C410 C410 100NF 100NF I NT ERNAL BNC-COAX BNC-COAX REF ERE NCE OUT ( r ear panel ) BAV99 BAV99 R506 R506 J22A J22A R509 R509 R510 R510 4.7K 4.7K U131 U131...
Page 168 Display & Keyboard, PCB 2, Component Layout 9-22 Schematic Diagrams...
Page 169 Display & Keyboard, PCB 2 100nF LM358 LM358 15.0 - 17.6 V 10uH 10BQ030 4.7uF-35V 4.7uF-35V 100nF +3.3V 22uF-6.3V 2.2uF-35V 4.7K 100nF 33pF LM358 +3.3V U 1A CTRL 100nF 4.7K BLM21A102S 470K 2.2uF-35V 100nF PGND 100nF TPS61045 Not used Not used FPC 20 LM358 820K...
Page 170 This page is intentionally left blank 9-24 Schematic Diagrams...
Page 171: Version B
Version B The descriptions in this section apply to instru- ments having a Sharp microprocessor. See General Information on page III for details on relevant serial numbers etc. Schematic Diagrams 9-25...
Page 172 This page is intentionally left blank. 9-26 Schematic Diagrams...
Page 173 Main Board, PCB 1, Component Layout, Bottom Side Schematic Diagrams 9-27...
Page 174 Main Board, PCB 1, Component Layout, Top Side 9-28 Schematic Diagrams...
Page 175 Main Schematic D[0..31] A[0..23] U15A U16A I/O0 I/O0 I/O1 I/O1 I/O2 I/O2 +3.3VD +3.3VMEM1 I/O3 I/O3 BLM41P800S I/O4 I/O4 I/O5 I/O5 I/O6 I/O6 I/O7 I/O7 +3.3VMEM2 I/O8 I/O8 I/O9 I/O9 BLM41P800S I/O10 I/O10 I/O11 I/O11 I/O12 I/O12 I/O13 I/O13 +3.3VMEM1 I/O14 I/O14 I/O15...
Page 176 This page is intentionally left blank. 9-30 Schematic Diagrams...
Page 177 CPU, Memories and Parts of the Counter Circuit, PCB 1, sheet 1(7) A[0..23] A[0..23] +3.3VCPU D[0..31] U13B R425 DQM[0..3] 1 TRST +3.3VCPU U54A U53A U17A R355 DF31 DF15 DF30 DF14 I/O0 DF29 DF13 I/O1 DF28 DF12 R629 R630 R631 R632 I/O2 DF27 DF11...
Page 178 This page is intentionally left blank. 9-32 Schematic Diagrams...
Page 179 Input Amplifiers, PCB 1, sheet 2(7) C496 R132 TRG_LVL_A R133 R134 2.5-10PF/250V -5.2VAI +5VAI +5VAI C100 C101 C102 C103 100NF R610 100NF 100NF +12VI +5VAI 1.2M 3.9pF-500V BAV99 BAV99 BAV99 BAV99 C104 C105 R135 C106 2.2UF-6.3V R136 R137 REAR PANEL INPUT A R138 C107 BAT18...
Page 180 This page is intentionally left blank. 9-34 Schematic Diagrams...
Page 181 Interpolators, PCB 1, sheet 3(7) R[0..3] AD [1..10] R505 R481 R484 R485 +12VINT U20A R513 R511 R508 R507 BLM21A102S C507 BF513 R524 C332 C321 6.8u-16V R377 100NF 2.2K R375 R376 R379 VREF+ 4.7K U11A VREF- U42A 1.5K COUNTER CIRCUIT C324 C325 R378 R383...
Page 182 This page is intentionally left blank. 9-36 Schematic Diagrams...
Page 183 Miscellaneous, PCB 1, sheet 4(7) PREKOD0 PREKOD1 PREKOD2 R564 FILTER_A +5VD C470 R418 2.2K R419 BC807-25 OPCLK 6.8K 1,2,6,7,8 +3.3VD IMP A P RE S CAL E R CONNE CT OR BLM21A102S PREKOD2 +5VD C471 C231 PREKOD1 100NF PREKOD0 PRESC TEST R421 2.2K R422...
Page 184 This page is intentionally left blank. 9-38 Schematic Diagrams...
Page 185 Oscillator Circuits, PCB 1, sheet 5(7) SPICLK SPIDATA +3.3V_PLL U47A R269 SPIPLL R270 SPIOVEN OVEN OSC ON/OFF LVC1G04 R271 C168 C169 DATA LOAD PLL R272 C170 3.3K R274 100P +3.3V_U4 R275 REFIN BLM21A102S OVE N OS C. MUXOUT C171 RFINA C173 100P STD OSC ON/OFF...
Page 186 This page is intentionally left blank. 9-40 Schematic Diagrams...
Page 187 Supply Voltages, PCB 1, sheet 6(7) U126 +5VU +3.3VA SENSE SHDN VTAP R482 R483 C396 3.3K 3.3K R449 C393 C394 100uF-6.3V 100uF-6.3V ERROR R584 OFFCTRL U29A LP2951CM R486 OF F +5VU -5.2VI -5.2VI +5VU R472 LVC74A R593 ONCTRL R594 R598 R602 R454 R455...
Page 188 This page is intentionally left blank. 9-42 Schematic Diagrams...
Page 189 Rear Panel, Interfaces and I/O, PCB 1, sheet 7/7 +3.3VEC C410 I NT E RNAL 100NF RE F E RE NCE OUT ( r ear panel ) BNC-COAX R509 R510 BAV99 R506 4.7K U131 J22A E XT E RNAL R512 C414 R583 ARMI NG...
Page 190 Display & Keyboard, PCB 2, Component Layout 9-44 Schematic Diagrams...
Page 191 Display & Keyboard, PCB 2 100nF LM358 LM358 15.0 - 17.6 V 10uH 10BQ030 4.7uF-35V 4.7uF-35V 100nF +3.3V 22uF-6.3V 2.2uF-35V 4.7K 100nF 33pF LM358 +3.3V U 1A CTRL 100nF 4.7K BLM21A102S 470K 2.2uF-35V 100nF PGND 100nF TPS61045 Not used Not used FPC 20 LM358 820K...
Page 192 This page is intentionally left blank. 9-46 Schematic Diagrams...
Page 193: Appendix
Chapter 10 Appendix...
Page 194: How To Replace Surface Mounted Devices
How to Replace Surface Mounted Devices Most of the components in this instrument are mounted on the surface of the board instead of through holes in the board. These components are not hard to replace but they require an- other technique. If you do not have special SMD desoldering equipment, follow the instructions below: Figure 10-7 Attach the IC to the pad with solder.
Page 195: Glossary
Electrostatic Discharge Glossary Calibration Ad- How to restore an instrument to perform in justments agreement with its specifications. Canadian Standards Association EN 61010-1 International safety standard FLASH PROM Electrically erasable and reprogrammable Almost all modern components have extremely thin conduc- non-volatile semiconductor memory.
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Page 197: Index
Chapter 11 Index...
Page 198 Index Frequency Range Interpolators ... . . 4-8,4-16 Performance Check ... 2-4 Troubleshooting ... . . 6-55 Adjustments Front Panel Microprocessor &...
Page 199 Processor Circuits Sensitivity External Reference Circuits 6-13,6-41 Description ....4-8,4-16 Performance Check ... 2-4 Input Amplifiers... 6-8,6-36 Protective Ground Signals.
Page 200 This page is intentionally left blank. 11-4 Index...

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