Anritsu MS2665C Service Manual
  1. Manuals
  2. Brands
  3. Anritsu Manuals
  4. Measuring Instruments
  5. MS2665C
  6. Service manual

Anritsu MS2665C Service Manual

Hide thumbs Also See for MS2665C:
Table of Contents

Advertisement

Quick Links

Download this manual
MS2665C/MS2667C/MS2668C
Spectrum Analyzer
Service Manual
Third Edition
To ensure that this equipment is used safely, im-
portant safety items are explained in the
MS2665C/MS2667C/MS2668C Spectrum Analyzer
Operation Manual. This manual explains impor-
tant service items related to service. Read both
the operation manual and this manual, and keep
both with the equipment.
Measuring Instruments Division
Measurement Group
ANRITSU CORPORATION
i
Document No.: M-W1335BE-3.0

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the MS2665C and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Related Manuals for Anritsu MS2665C

Summary of Contents for Anritsu MS2665C

  • Page 1 Third Edition To ensure that this equipment is used safely, im- portant safety items are explained in the MS2665C/MS2667C/MS2668C Spectrum Analyzer Operation Manual. This manual explains impor- tant service items related to service. Read both the operation manual and this manual, and keep both with the equipment.
  • Page 2 Always request repair by a trained engineer who understands the hazards. Anritsu Corporation will not accept liability for any injuries sustained as a result of opening the equipment covers.
  • Page 3 Part Names & Part Numbers Please specify the part numbers shown in the parts list when making inquiries or when ordering parts. There may be a difference between the names of parts used in this manual and the parts actually used in the equipment or supplied for repair. This is because equivalent parts with the same functions, performance and reliability as the parts specified in the circuit diagrams and parts list have been used or supplied.

  • Page 5: Table Of Contents

    Table of Contents For Safety ............Section 1 General......... Section 2 MS2665C ........2.1 Overall Circuit description ..........2.2 Troubleshooting .............. 2.3 Mechanical configuration ..........2-31 Section 3 MS2667C ........3.1 Overall Circuit description ..........3.2 Troubleshooting .............. 3.3 Mechanical configuration ..........

  • Page 7: Section 1 General

    Refer to the separate operation manual for handling the instruments. Our basic policy to the repair to the factory system, i.e. the defective instruments should be returned to Anritsu for repair. However, it may be time consuming and some kinds of repairs can be easily done in the field.
  • Page 8 Section 1 General...
  • Page 9 Section 2 MS2665C Overall Circuit description ............Troubleshooting ................. 2.2.1 Introduction ..............2.2.1.1 Service kit ............2.2.1.2 Required equipment ........2.2.1.3 Circuit reference ..........2-10 2.2.2 Detecting faulty module ..........2-13 2.2.3 Disassembling cabinet ........... 2-15 2.2.4 Replacement of faulty module ........2-15 2.2.5 Adjustment after module replacement ......

  • Page 10: Overall Circuit Description

    MS2665C is a superheterodyne system scanning-type spectrum analyzer. This section describes overall circuit of the MS2665C spectrum analyzer with its block diagram. An RF input signal after passing through an RF switch and variable RF ATTN in 21 GHz S-ATT is switched by PIN diode switch in 21 GHz YTF/SW to two different signal routes depending on input RF frequency.
  • Page 11 2.1 Overall Circuit description At the IF section the incoming signal is divided into two paths. The main route leads to image rejection filters while the second, a highly attenuated feeler path signal is used for generation of wide band trigger signal in TRIG/GATE section ( option 06) situated on OPTION BASE board.
  • Page 12 Section 2 MS2665C...
  • Page 13 2.1 Overall Circuit description...

  • Page 14: Section 2 Ms2665C

    Section 2 MS2665C...
  • Page 15 2.1 Overall Circuit description...
  • Page 16 Section 2 MS2665C...

  • Page 17: Troubleshooting

    2.2.1.2 Required equipment Table 2-2-2 shows the equipment to prepare for overall adjustment of the spectrum analyzer. Table 2-2-2 Required equipment Nomenclature Model number Manufacture Synthesized signal generator MG3633A Anritsu Frequency counter MF76A Anritsu Swept frequency synthesizer 6769B Anritsu two Power meters...

  • Page 18: Circuit Reference

    Section 2 MS2665C 2.2.1.3 Circuit reference This paragraph supplies the exchangeable module list of the spectrum analyzer with its overall circuit diagram. Table 2-2-3 Exchange modules of the MS2665C Schematic number Name Model number Ordering number Note A01 MOTHER BOARD...
  • Page 19 2.2 Troubleshooting 2-11...
  • Page 20 Section 2 MS2665C 2-12...

  • Page 21: Detecting Faulty Module

    2.2 Troubleshooting 2.2.2 Detecting faulty module The flowchart shows the way to locate the faulty module among them. POWER ON [Location of faulty module] LEDs come on? Fuse, A02 FRONT BOARD, POWER SUPPLY UNIT The LCD comes on? A03 CPU, TFT LCD MODULE, POWER SUPPLY UNIT Fan Movement? A02 FRONT BOARD, POWER SUPPLY UNIT Key, Rotary knob come on?
  • Page 22 Section 2 MS2665C After executing internal calibration, you can locate the faulty module using “Cal Status” (as shown below). “Cal Status” can be displayed by the key operation : open the second page of Cal menu with “More” key, and press “F5” key.

  • Page 23: Disassembling Cabinet

    2.2 Troubleshooting 2.2.3 Disassembling cabinet Refer to 2.3.1. 2.2.4 Replacement of faulty module Refer to 2.3.2 to 2.3.5. 2-15...

  • Page 24: Adjustment After Module Replacement

    Section 2 MS2665C 2.2.5 Adjustment after module replacement This paragraph describes the overall adjustment required after replacement of any modules in following Table. Look for modules which you replaced in Table. Please carry out work corresponding to module which you replaced. This adjust- ment is not necessary, if the module you replaced does not belong to the following Table.
  • Page 25 2.2 Troubleshooting (1) Connect the spectrum analyzer Buff Out (on its rear panel) to MG3633A REF INPUT (on its rear panel). (2) Connect the MG3633A OUTPUT to MF76A Input. (3) Connect the MF76A EREQ STD 10 MHz IN (on its rear panel) to 10 MHz standard signal. And set the EXT/INT selector switch to EXT.

  • Page 26: Sweep Adjustment

    Section 2 MS2665C 2.2.5.2 Sweep adjustment Required equipment : (1) 6769B Swept frequency synthesizer, (2) MG3633A Synthesized signal generator, (3) HP3478A Digital multimeter. Setup for the procedure (1), (2) : MG3633A The spectrum analyzer Output RF Input Fig. 2-2-3 Connect the spectrum analyzer RF Input to MG3633A OUTPUT.
  • Page 27 2.2 Troubleshooting Procedure : (1) Local sweep adjustment Initialize the spectrum analyzer and the MG3633A. 1) Set the spectrum analyzer to : Center frequency, 100 MHz Span, 100 kHz Set the MG3633A output to : LEVEL, -10 dBm Frequency, 100 MHz (CW) Press “→CF”...
  • Page 28 Section 2 MS2665C (3) YTF tuning DAC adjustment 1) Turn the spectrum analyzer on, while pushing “0” key, and initialize the spectrum analyzer. 2) Set the spectrum analyzer to zero Span. 3) Enter Cal menu by pushing “Shift + 0” keys. Open the second page of the Cal menu, and enter Maintenance menu with “F6”...
  • Page 29 2.2 Troubleshooting 7) Enter Cal menu by pushing “Shift + 0” keys. Enter Pre-selector Tuning menu with “F6” key. 8) Press “F2” key and set Pre-selector bias value to 0, using the data keys or the knob on the front panel. 9) Adjust the variable resistor R31 on A13 MICRO CONVERTER (refer to Fig.
  • Page 30 Section 2 MS2665C (6) Confirmation of YTF tuning Initialize the spectrum analyzer and the 6769B. 1) Set the spectrum analyzer to : Start frequency, 3 GHz Stop frequency, 21 GHz Log Scale, 2 dB Storage Max Hold (Press “A, B” key, press “F5” key and “F2” key).
  • Page 31 2.2 Troubleshooting Jumper pin X12 R22, R31, R57, R60, R68 Fig. 2-2-6 The location of adjusters on A13 MICRO CONVERTER 2-23...

  • Page 32: If1 (Att), If2 (Amp) Adjustment

    Section 2 MS2665C 2.2.5.3 IF1 (ATT), IF2 (AMP) adjustment Required equipment : (1) 6769B swept frequency synthesizer (2) ML4803A Power meter (3) MA4705A Power sensor (4) IBM PC/AT compatible Setup : (1) Connect the spectrum analyzer RF Input to 6769B RF OUTPUT...
  • Page 33 2.2 Troubleshooting (9) Enter RF/MICRO CONVERTER maintenance menu, and open its 6th page : 1) Enter Cal menu by pushing “Shift + 0” key. Open the second page of the Cal menu, 2) Enter maintenance menu with “F6” key, 3) Enter RF/Micro Converter maintenance menu with “F2” key. Open the 6th page of the RF/Micro Converter maintenance menu (Press “More”...

  • Page 34: Checking Items After Assembling Cabinet

    Section 2 MS2665C (20) Write the compensation value of adjusted IF-Gain 1 and IF-Gain 2 to the spectrum analyzer’s Flash Memory with Flash Memory writing command “CDW” from personal computer. For example : CMD > MENTE P2110 ON CMD > CD40 1, 0 CMD >...

  • Page 35: Frequency Response Compensation

    2.2 Troubleshooting 2.2.8 Frequency response compensation Perform Frequency response compensation, when one of the following modules is replaced. This Frequency response compensation is not necessary, if the module you replaced does not belong to the following modules. • A03 CPU •...
  • Page 36 Section 2 MS2665C Setup : IBM-PC/AT Compatible GP-IB control The spectrum analyzer 6769B RF Output RF Input 3 dB attenuator Power meter : ML4803A (for MS2665C) ML2437A (for MS2667/68C) 3 dB attenuator MG3633A Power sensor : MA4705A (for MS2665C) MA2444A (for MS2667/68C)
  • Page 37 2.2 Troubleshooting (1) At the measurement of frequency response, connect the spectrum analyzer’s RF Input to 6769B RF OUTPUT through a signal feeder. The signal feeder consists of a coaxial cable (e.g. SUCOFLEX) less than 1 m length and two 3 dB attenuators attached to each end of the cable.
  • Page 38 (9) Measure the 6769B power output with “6769B output calibration” program. 1) Connect the 6769B RF OUTPUT to the MA4601A (for MS2665C) or MA2444A (for MS2667/68C) through a signal feeder. The signal feeder consists of a coaxial cable (e.g. SUCOFLEX) less than 1 m length and two 3 dB attenuators attached to each end of the cable.

  • Page 39: Mechanical Configuration

    2.3 Mechanical configuration 2.3 Mechanical configuration 2.3.1 Disassembling/Assembling cabinet (1) Removing Feet ( Remove the S1/S2/S3 screws and remove the S3 screw of the rear. (2) Removing around cover Remove the four S1 screws ( ) and remove the S3 screw of the rear. Remove the around cover to pull backward.
  • Page 40 Section 2 MS2665C 2-32...
  • Page 41 2.3 Mechanical configuration Fig. 2-3-1 2-33...
  • Page 42 Section 2 MS2665C 2-34...

  • Page 43: Removing/Assembling Units And Pc Boards

    2.3 Mechanical configuration 2.3.2 Removing/Assembling units and PC boards (1) Removing MICRO CONVERTER and 1ST LO AMP After removing the screws and each cables, remove the to pull backward. (2) Removing Step Attenuator Band ATT Angle After removing the S1/S2 screws, remove the (3) Removing 21 GHz YTF/SW After removing the Angle , remove the...
  • Page 44 Section 2 MS2665C 2-36...
  • Page 45 2.3 Mechanical configuration Fig. 2-3-2 2-37...
  • Page 46 Section 2 MS2665C Fig. 2-3-3 2-38...

  • Page 47: Front Unit Disassembly/Assembly

    2.3 Mechanical configuration 2.3.3 Front unit disassembly/assembly Removing TFT LCD MODULE (1) After removing the S1, S2 screws and encoder knob , remove the front panel (2) After removing the S3 screw, remove the to pull forward. (3) After removing the S4 screw and each cables, remove the LCD To assemble, perform inversely.
  • Page 48 Section 2 MS2665C 2-40...
  • Page 49 2.3 Mechanical configuration Fig. 2-3-4 2-41...
  • Page 50 Section 2 MS2665C 2-42...

  • Page 51: A09 Option Base Disassembly/Assembly

    2.3 Mechanical configuration 2.3.4 A09 OPTION BASE disassembly/assembly Parts List 34Y106684 A09 OPTION BASE 34Y106695 A0901 TRIG/GATE 34Y106699 A0902 AM/FM MONITOR 34Y106697 A0903 TV MONITOR 34Y113473 A0904 QP DETECTOR or 34Y117105 2-43...
  • Page 52 Section 2 MS2665C 2-44...
  • Page 53 2.3 Mechanical configuration Fig. 2-3-5 2-45...
  • Page 54 Section 2 MS2665C 2-46...
  • Page 55 2.3 Mechanical configuration 2.3.5 Removing/Assembling A0501 HI-SPEED AD from A05 SCAN/AD Parts List 34Y112923A A05 SCAN/AD or 34Y112923C 34Y106688 A0501 HI-SPEED AD Fig. 2-3-6 2-47...
  • Page 56 Section 2 MS2665C 2-48...
  • Page 57 Section 3 MS2667C Overall Circuit description ............Troubleshooting ................. 3.2.1 Introduction ..............3.2.1.1 Service kit ............3.2.1.2 Required equipment ......... 3.2.1.3 Circuit reference ..........3-10 3.2.2 Detecting faulty module ..........3-15 3.2.3 Disassembling cabinet ........... 3-16 3.2.4 Replacement of faulty module ........3-16 3.2.5 Adjustment after module replacement ......

  • Page 58: Overall Circuit Description

    Section 3 MS2667C 3.1 Overall Circuit description MS2667C is a superheterodyne system scanning-type spectrum analyzer. This section describes overall circuit of the MS2667C spectrum analyzer with its block diagram. An RF input signal after passing through an RF switch and variable RF ATTN in Switched Attenuator is switched by Diplexing Bandswitch to two different signal routes depending on input RF frequency.
  • Page 59 3.1 Overall Circuit description At the IF section the incoming signal is divided into two paths. The main route leads to image rejection filters while the second, a highly attenuated feeler path signal is used for generation of wide band trigger signal in TRIG/GATE section (option 06) situated on OPTION BASE board.
  • Page 60 Section 3 MS2667C...
  • Page 61 3.1 Overall Circuit description...

  • Page 62: Section 3 Ms2667C

    Section 3 MS2667C...
  • Page 63 3.1 Overall Circuit description...
  • Page 64 Section 3 MS2667C...

  • Page 65: Troubleshooting

    3.2.1.2 Required equipment Table 3-2-1 shows the equipment to prepare for overall adjustment of the spectrum analyzer. Table 3-2-1 Required equipment Nomenclature Model number Manufacture Synthesized signal generator MG3633A Anritsu Frequency counter MF76A Anritsu Swept frequency synthesizer 6769B Anritsu Power meter...

  • Page 66: Circuit Reference

    Section 3 MS2667C 3.2.1.3 Circuit reference This paragraph supplies the exchange module list of the spectrum analyzer with its overall circuit diagram. Table 3-2-2 Exchange Modules of MS2667C Schematic number Name Model name Ordering number Note MOTHER BOARD MM200013A 34Y115415 A02 FRONT BOARD 322U14223 34Y118357...
  • Page 67 3.2 Troubleshooting (4) Press Key “more” 3 times. MAINTENANCE (4/4) page appears. Check YTF model. If “09 : YTF MODEL” is not indicated, order “F2626”. If “09 : YTF MODEL” is indicated, order same model which is indicated. YTF Model 2nd Converter (Schematic number 9) and YTF (Schematic number 14) forms a pair.
  • Page 68 Section 3 MS2667C 3-12...
  • Page 69 3.2 Troubleshooting 3-13...
  • Page 70 Section 3 MS2667C 3-14...

  • Page 71: Detecting Faulty Module

    3.2 Troubleshooting 3.2.2 Detecting faulty module The flowchart shows the way to locate the faulty module among them. POWER ON [Location of faulty module] LEDs come on? Fuse, A02 FRONT BOARD, POWER SUPPLY UNIT The LCD comes on? A03 CPU, TFT LCD MODULE, POWER SUPPLY UNIT Fan Movement? POWER SUPPLY UNIT Key, Rotary knob come on?

  • Page 72: Disassembling Cabinet

    Section 3 MS2667C 3.2.3 Disassembling cabinet Refer to 3.3.1. 3.2.4 Replacement of faulty module Refer to 3.3.2 to 3.3.8. 3.2.5 Adjustment after module replacement This paragraph describes the overall adjustment required after replacement of any modules in following Table. Look for modules which you replaced in Table.
  • Page 73 3.2 Troubleshooting Setup for the procedure (1), (2) : MG3633A The spectrum analyzer Output RF Input Fig. 3-2-1 Connect the spectrum analyzer RF Input to MG3633A OUTPUT. Setup for the procedure (3) : (1) Connect digital multimeter HI input to the X3 terminal on LOCAL-SP2 PC board. (Refer to Fig. 3-2-4) (2) Connect digital multimeter LO input to the spectrum analyzer’s common.
  • Page 74 Section 3 MS2667C (3) Connect the spectrum analyzer RF Input to 6769B RF OUTPUT. 6769B The spectrum analyzer RF Output RF Input Fig. 3-2-3 3-18...
  • Page 75 3.2 Troubleshooting Procedure : (1) Local sweep adjustment Initialize the spectrum analyzer and the MG3633A. 1) Set the spectrum analyzer to : Center frequency, 100 MHz Span, 100 kHz Set the MG3633A output to : LEVEL, -10 dBm Frequency, 100 MHz (CW) Press “→CF”...
  • Page 76 Section 3 MS2667C (3) YTF offset voltage adjustment 1 1) Set the spectrum analyzer. Center frequency : 4 GHz Span : 400 MHz 2) On the spectrum analyzer, press “single” key. 3) After sweep of the spectrum analyzer is finished, check the X3 voltage (multimeter indicated). This voltage value is V1.
  • Page 77 3.2 Troubleshooting R280 R53, R57 R287 R123 Fig. 3-2-4 The location of adjusters on LOCAL-SP2 and RF CONVERTER 3-21...
  • Page 78 Section 3 MS2667C (5) YTF tuning DAC adjustment 1) Turn the spectrum analyzer on, while pushing “0” key, and initialize the spectrum analyzer. 2) Set the spectrum analyzer to zero Span. 3) Enter Cal menu by pushing “Shift + 0” keys. Open the second page of the Cal menu, and enter Maintenance menu with “F6”...
  • Page 79 3.2 Troubleshooting 8) Select key “Mainte RF/Micro Conv” (F2), and press the key “more”. 9) Press the key “Main Swp → off” (F2). At this point YTF filter shape appears on the display of the spectrum analyzer. 10) Adjust R79 on the 2nd Converter (refer to Fig. 3-2-5) so as to shift the center of filter display about 5 MHz below the center frequency of the display.
  • Page 80 Section 3 MS2667C 10 dB down point Center frequency (20 GHz) (7) YTF Sweep adjustment 1) Initialize the spectrum analyzer (Press key “preset”, followed by Key “F1”). 2) Set 6769B Signal generator output to : Frequency : 22.2 GHz RF level : -10 dBm 3) Set Marker of the spectrum analyzer to 22.2 GHz (Press keys “Marker”...
  • Page 81 3.2 Troubleshooting Jumper pin X12 R27, R30, R41, R42 R70, R79, X3, X10, Fig. 3-2-5 The location of adjusters on 2nd CONVERTER 3-25...

  • Page 82: If Gain-1 (Att), If Gain-2 (Amp) Of Internal Mixer Band Adjustment

    Section 3 MS2667C 3.2.5.3 IF Gain-1 (ATT), IF Gain-2 (AMP) of Internal Mixer Band adjustment Required equipment : (1) 6769B swept frequency synthesizer (2) ML2437A Power sensor (3) MA2444A Power sensor Setup : (1) Connect RF Input of the spectrum analyzer to RF OUTPUT of 6769B. Procedure : (1) Keep key “0”...
  • Page 83 3.2 Troubleshooting (9) Enter RF/Micro Conv maintenance menu, and open its 6th page : 1) Enter Cal menu by pushing “Shift” + “0” keys. Open second page of Cal menu by pushing “more”. 2) Enter maintenance menu with “F6” (Maintenance) key. 3) Enter RF/Micro Converter maintenance menu with “F2”...
  • Page 84 Section 3 MS2667C [ Band 2+ ] (19) Set Manual Band to Band 2+ : 1) Enter Frequency menu by pushing “Frequency” key, and open its second page with “more” key. 2) Enter Internal mixer Band menu with “F1” (Internal Mix) key and open its second page with “more” key. 3) Set manual band to Band 2+ by pushing “F2”...
  • Page 85 3.2 Troubleshooting [ Band 4+ ] (33) Set Manual Band to Band 4+ : 1) Enter Frequency menu by pushing “Frequency” key, and open its second page with “more” key. 2) Enter Internal mixer Band menu with “F1” (Internal Mix) key and open its second page with “more” key. 3) Set manual band to Band 4+ by pushing “F4”...

  • Page 86: If Gain-1 (Att), If Gain-2 (Amp) Of External Mixer Band Adjustment

    Section 3 MS2667C 3.2.5.4 IF Gain-1 (ATT), IF Gain-2 (AMP) of External Mixer Band adjustment Required equipment : (1) MG3633A Synthesized signal generator (2) ML2437A Power sensor (3) MA2444A Power sensor Setup : (1) Connect 1st Local output connector of the spectrum analyzer to RF OUTPUT of MG3633A by cable. (2) Connect REF OUTPUT connector of MG3633A to REF In of the spectrum analyzer.
  • Page 87 3.2 Troubleshooting (9) Set IF Gain-1 and IF Gain-2 values to 0. 1) Press “F4” (IF Gain-1) + “0” + “enter” keys and on display appears a writing “IF Gain1 set to 0”. 2) Press “F5” (IF Gain-2) + “0” + “enter” keys and on display appears a writing “IF Gain2 set to 0”. (10) Adjust IF Gain 1 and IF Gain 2 so that marker reading becomes -10 dBm ±0.5 dB.

  • Page 88: Assembling Cabinet

    Section 3 MS2667C 3.2.6 Assembling cabinet Refer to 3.3.1. 3.2.7 Checking items after assembling cabinet Refer to 2.2.7. 3.2.8 Frequency response compensation Perform Frequency response compensation, when one of the following modules is replaced. This Frequency response compensation is not necessary, if the module you replaced does not belong to the following modules. •...

  • Page 89: Mechanical Configuration

    3.2 Troubleshooting 3.3 Mechanical configuration 3.3.1 Disassembling/Assembling cabinet (1) Removing Feet ( Remove the S1 screws and remove the S2/S3 screws of the rear. (2) Removing around cover ( Remove the four S1 screws ( ) and remove the S3 screw of the rear. Remove the around cover ( ) to pull backward.
  • Page 90 Section 3 MS2667C 3-34...
  • Page 91 3.3 Mechanical configuration Fig. 3-3-1 3-35...
  • Page 92 Section 3 MS2667C 3-36...

  • Page 93: Removing/Assembling Units And Pc Boards

    3.3 Mechanical configuration 3.3.2 Removing/Assembling units and PC boards Removing RF CONVERTER , PC Boards ( ), Power Supply (1) After 3.3.1 (2) removing procedure, remove the S1/S2/S3/S4/S5 screws and remove the rear panel (2) Removing PC Boards ( After (1) removing procedure, remove PC Boards ( ) to pull backward.
  • Page 94 Section 3 MS2667C 3-38...
  • Page 95 3.3 Mechanical configuration Fig. 3-3-2 3-39...
  • Page 96 Section 3 MS2667C 3-40...

  • Page 97: Disassembling/Assembling Components Around Rf Input

    3.3 Mechanical configuration 3.3.3 Disassembling/Assembling Components around RF Input Removing Diplexing Bandswitch , Switched Attenuator , AK-AKF PANEL Connector (1) Removing Diplexing Bandswitch After 3.3.1 (2) removing procedure, remove the S1 screws and Disconnect Diplexing Bandswitch’s connector which is connected to Swithched Attenuator (2) Removing Switched Attenuator 1) After (1) procedure, remove the S2/S3/S4/S5/S6 screws and remove encorder knob and the front panel...
  • Page 98 Section 3 MS2667C 3-42...
  • Page 99 3.3 Mechanical configuration Fig. 3-3-3 3-43...
  • Page 100 Section 3 MS2667C 3-44...

  • Page 101: Disassembling/Assembling Units And Components On Lower Surface

    3.3 Mechanical configuration 3.3.4 Disassembling/Assembling Units and Components on lower surface Caution : 30GHz YTF (MM200001A) is attached to the plate , to form the module, by the S4 screws which is tightened at pre-determined torque of 6kg. If torque of the S4 screws is changed, the performance specification of 30GHz YTF will be affected.
  • Page 102 Section 3 MS2667C Assembling 2nd CONVERTER ,1st LO Amp , YTF , 30GHz H.MIXER (1) Assembling 2nd CONVERTER Perform removing procedure (1) inversely. (2) Assembling 1st LO Amp Perform removing procedure (2) inversely. (3) Assembling YTF (For F2626) If YTF is OPEN LOOP YIG FILTER (F2626), perform this assembling procedure. If YTF is 30GHz YTF (MM200001A), please perform (4) assembling procedure.
  • Page 103 4) Attach the plate and tighten the N1 nuts. Caution : Use MODEL 01-201 TORQUE WRENCH (Anritsu) when connectors, which are connected to YTF (F2626) , are tightened. If there is not it, use torque wrench whose torque is 8 IN-LBS.
  • Page 104 Section 3 MS2667C 3-48...
  • Page 105 3.3 Mechanical configuration 3-49...
  • Page 106 Section 3 MS2667C 3-50...

  • Page 107: Front Unit Disassembly/Assembly

    3.3 Mechanical configuration 3.3.5 Front unit disassembly/assembly Remove TFT LCD MODULE (1) After 3.3.3 (2) 1) and 2) procedures, remove the S3 screws and remove to pull forward. (2) After removing the S4 screws and each cables, remove the LCD To assemble, perform inversely Parts List 322B13832...
  • Page 108 Section 3 MS2667C 3-52...
  • Page 109 3.3 Mechanical configuration Fig. 3-3-6 3-53...
  • Page 110 Section 3 MS2667C 3-54...

  • Page 111: Option Base Disassembly/Assembly

    3.3 Mechanical configuration 3.3.6 OPTION BASE disassembly/assembly Parts List 34Y106684B OPTION BASE 34Y106695B A0901 TRIG/GATE 34Y106699B A0902 AM/FM MONITOR None None 3-55...
  • Page 112 Section 3 MS2667C 3-56...
  • Page 113 3.3 Mechanical configuration Fig. 3-3-7 3-57...
  • Page 114 Section 3 MS2667C 3-58...

  • Page 115: Removing/Assembling A0501 Hi-Speed Ad From Scan/Ad

    3.3 Mechanical configuration 3.3.7 Removing/Assembling A0501 HI-SPEED AD from SCAN/AD Parts List 34Y112923D SCAN/AD 34Y106688 A0501 HI-SPEED AD Fig. 3-3-8 3-59...

  • Page 116: Connecting The Cable To Diplexing Bandswitch And F2626 (Ytf)

    Section 3 MS2667C 3.3.8 Connecting the cable to Diplexing Bandswitch and F2626 (YTF) (1) Connecting the cable to Diplexing Bandswitch Connect each wire of the cable to following terminal of Diplexing Bandswitch. • Red (#2) wire to #1 pin of Diplexing Bandswitch •...
  • Page 117 Section 4 MS2668C Overall Circuit description ............4-2 Troubleshooting ................. 4-9 4.2.1 Introduction ..............4-9 4.2.1.1 Service kit ............4-9 4.2.1.2 Required equipment ........4-9 4.2.1.3 Circuit reference ..........4-10 4.2.2 Detecting faulty module ..........4-15 4.2.3 Disassembling cabinet ........... 4-16 4.2.4 Replacement of faulty module ........

  • Page 118: Overall Circuit Description

    Section 4 MS2668C 4.1 Overall Circuit description MS2668C is a superheterodyne system scanning-type spectrum analyzer. This section describes overall circuit of the MS2668C spectrum analyzer with its block diagram. An RF input signal after passing through an RF switch and variable RF ATTN in Switched Attenuator is switched by Diplexing Bandswitch to two different signal routes depending on input RF frequency.
  • Page 119 4.1 Overall Circuit description In the instrument, a high accuracy 625 kHz signal is present for level accuracy calibration. This signal is generated by frequency-dividing the 10 MHz reference signal, and its power level is varied with 1 dB steps by CAL ATT. Internal calibration operation being carried out, this calibrating signal is fed to the RF signal-route through the switch in Switched Attenuator.
  • Page 120 Section 4 MS2668C...
  • Page 121 4.1 Overall Circuit description...

  • Page 122: Section 4 Ms2668C

    Section 4 MS2668C...

  • Page 123: Overall Circuit Description

    4.1 Overall Circuit description...
  • Page 124 Section 4 MS2668C...

  • Page 125: Troubleshooting

    4.2 Troubleshooting 4.2 Troubleshooting 4.2.1 Introduction This section describes how to troubleshoot the MS2668C. 4.2.1.1 Service kit Refer to 2.2.1.1. 4.2.1.2 Required equipment Refer to 3.2.1.2.

  • Page 126: Circuit Reference

    Section 4 MS2668C 4.2.1.3 Circuit reference This paragraph supplies the exchange module list of the spectrum analyzer with its overall circuit diagram. Table 4-2-1 Exchange Modules of MS2668C Schematic number Name Model name Ordering number Note MOTHER BOARD MM200013A 34Y115415 A02 FRONT BOARD 322U14223 34Y118357...
  • Page 127 4.2 Troubleshooting (4) Press Key “more” 3 times. MAINTENANCE (4/4) page appears. Check YTF model. If “09 : YTF MODEL” is not indicated, order “F2626”. If “09 : YTF MODEL : F2626” is indicated, order “F2626 MODULE”. If “09 : YTF MODEL : MLFP1312” is indicated, order “MLFP1312 MODULE”. YTF Model When you replace a A02 FRONT BOARD or A03 CPU, check circuit board number (322U******) of A03 CPU.
  • Page 128 Section 4 MS2668C 4-12...
  • Page 129 4.2 Troubleshooting 4-13...
  • Page 130 Section 4 MS2668C 4-14...

  • Page 131: Detecting Faulty Module

    4.2 Troubleshooting 4.2.2 Detecting faulty module The flowchart shows the way to locate the faulty module among them. POWER ON [Location of faulty module] LEDs come on? Fuse, A02 FRONT BOARD, POWER SUPPLY UNIT The LCD comes on? A03 CPU, TFT LCD MODULE, POWER SUPPLY UNIT Fan Movement? POWER SUPPLY UNIT Key, Rotary knob come on?

  • Page 132: Disassembling Cabinet

    Section 4 MS2668C 4.2.3 Disassembling cabinet Refer to 4.3.1. 4.2.4 Replacement of faulty module Refer to 4.3.2 to 4.3.8. 4.2.5 Adjustment after module replacement This paragraph describes the overall adjustment required after replacement of any modules in following Table. Look for modules which you replaced in Table.
  • Page 133 4.2 Troubleshooting Setup for the procedure (1), (2) : MG3633A The spectrum analyzer Output RF Input Fig. 4-2-1 Connect the spectrum analyzer RF Input to MG3633A OUTPUT. Setup for the procedure (3) : (1) Connect digital multimeter HI input to the X3 terminal on LOCAL-SP2 PC board. (Refer to Fig. 3-2-4) (2) Connect digital multimeter LO input to the spectrum analyzer’s common.
  • Page 134 Section 4 MS2668C (3) Connect the spectrum analyzer RF Input to 6769B RF OUTPUT. 6769B The spectrum analyzer RF Output RF Input Fig. 4-2-3 4-18...
  • Page 135 4.2 Troubleshooting Procedure : (1) Local sweep adjustment Refer to 3.2.5.2 Procedure (1) Local sweep adjustment. (2) YTO FM sweep adjustment Refer to 3.2.5.2 Procedure (2) YTO FM sweep adjustment. (3) YTF offset voltage adjustment 1 Refer to 3.2.5.2 Procedure (3) YTF offset voltage adjustment 1. (4) YTF offset voltage adjustment 2 Refer to 3.2.5.2 Procedure (4) YTF offset voltage adjustment 2.
  • Page 136 Section 4 MS2668C 10) Adjust R79 on the 2nd Converter (refer to Fig. 3-2-5) so as to shift the center of filter display about 5 MHz below the center frequency of the display. 5 MHz 10 dB down point The center of filter Center frequency (3.2 GHz) 11) Set the spectrum analyzer to :...
  • Page 137 4.2 Troubleshooting 10 dB down point Center frequency (30 GHz) (7) YTF Sweep adjustment 1) Initialize the spectrum analyzer (Press key “preset”, followed by Key “F1”). 2) Set 6769B Signal generator output to : Frequency : 26.2 GHz RF level : -10 dBm 3) Set Marker of the spectrum analyzer to 26.2 GHz (Press keys “Marker”...

  • Page 138: If Gain-1 (Att), If Gain-2 (Amp) Of Internal

    Section 4 MS2668C 4.2.5.3 IF Gain-1 (ATT), IF Gain-2 (AMP) of Internal Mixer Band adjustment Required equipment : (1) 6769B swept frequency synthesizer (2) ML2437A Power sensor (3) MA2444A Power sensor Setup : (1) Connect RF Input of the spectrum analyzer to RF OUTPUT of 6769B. Procedure : (1) Keep key “0”...
  • Page 139 4.2 Troubleshooting (10) Set IF Gain-1 and IF Gain-2 values to 0. 1) Press “F4” (IF Gain-1) + “0” + “enter” keys and on display appears a writing “IF Gain1 set to 0”. 2) Press “F5” (IF Gain-2) + “0” + “enter” keys and on display appears a writing “IF Gain2 set to 0”. (11) Adjust IF Gain 1 and IF Gain 2 so that marker reading becomes -12 dBm ±0.5 dB.
  • Page 140 Section 4 MS2668C (21) Adjust the 6769B output level to make power meter reading -10 dBm at end of cable feeding the signal to the spectrum analyzer, and then connect the cable to the spectrum analyzer’s RF Input. (22) Tune the spectrum analyzer’s pre-selector (refer to procedure (7)). (23) Enter RF/Micro Conv maintenance menu, and open its 6th page (refer to procedure (9)).

  • Page 141: Mixer Band Adjustment

    4.2 Troubleshooting (35) Adjust the 6769B output level to make power meter reading -10 dBm at end of cable feeding the signal to the spectrum analyzer, and then connect the cable to the spectrum analyzer’s RF Input. (36) Tune the spectrum analyzer’s pre-selector (refer to procedure (7)). (37) Enter RF/Micro Conv maintenance menu, and open its 6th page (refer to procedure (9)).

  • Page 142: Assembling Cabinet

    Section 4 MS2668C 4.2.6 Assembling cabinet Refer to 4.3.1. 4.2.7 Checking items after assembling cabinet Refer to 2.2.7. 4.2.8 Frequency response compensation Perform Frequency response compensation, when one of the following modules is replaced. This Frequency response compensation is not necessary, if the module you replaced does not belong to the following modules. •...

  • Page 143: Mechanical Configuration

    4.3 Mechanical configuration 4.3 Mechanical configuration 4.3.1 Disassembling/Assembling cabinet Refer to 3.3.1. 4.3.2 Removing/Assembling units and PC boards Refer to 3.3.2. 4.3.3 Disassembling/Assembling Components around RF Input Refer to 3.3.3. 4.3.4 Disassembling/Assembling Units and Components on lower surface Caution : For F2626 MODULE and MLFP1312 MODULE (A label printed “Model number”...
  • Page 144 Section 4 MS2668C (4) Removing YTF (For F2626 MODULE or MLFP1312 MODULE) If YTF is F2626 MODULE or MLFP1312 MODULE, perform this removing procedure. If YTF is OPEN LOOP YIG FILTER (F2626), perform (3) removing procedure. 1) After 3.3.1 (2) removing procedure, remove the N1 nuts and remove the plate (YTF , 40GHz H.MIXER , Coupler/Amp...
  • Page 145 4.3 Mechanical configuration (3) Assembling YTF (For F2626) If YTF is OPEN LOOP YIG FILTER (F2626), perform this assembling procedure. If YTF is F2626 MODULE or MLFP1312 MODULE, please perform (4) assembling procedure. 1) Tighten the S4 screws. 2) Connect 40GHz H.MIXER’s connector to YTF ’s connector.
  • Page 146 Section 4 MS2668C Caution : Use MODEL 01-201 TORQUE WRENCH (Anritsu) when connectors, which are connected to YTF , are tight- ened. If there is not it, use torque wrench whose torque is 8 IN-LBS. Parts List 34Y117228 2nd CONVERTER...
  • Page 147 4.3 Mechanical configuration 4-31...
  • Page 148 Section 4 MS2668C 4-32...

  • Page 149: Front Unit Disassembly/Assembly

    4.3 Mechanical configuration 4.3.5 Front unit disassembly/assembly Refer to 3.3.5. 4.3.6 A09 OPTION BASE disassembly/assembly Refer to 3.3.6. 4.3.7 Removing/Assembling A0501 HI-SPEED AD from A05 SCAN/AD Refer to 3.3.7. 4.3.8 Connecting the cable to Diplexing Bandswitch and F2626 (YTF) Refer to 3.3.8. 4-33...
  • Page 150 Section 4 MS2668C 4-34.

  • Page 151: Section 5 Firmware Installation

    Section 5 Firmware installation To install software, it needs 2 memory cards. Card 1 includes installer software. Card 2 includes spectrum analyzer firmware. Installation process is as follows. Refer to paragraph 2.3.1, on disassembly/assembly cabinet. (1) Switch off the instrument and remove the AC cord. (2) Place spectrum analyzer vertically with display facing down.
  • Page 152 Section 5 Firmware installation...

  • Page 153: Section 6 Performance Test System

    Section 6 Performance test system The following describes the summary of the performance test system on MS2665C/MS2667C/MS2668C. This test sys- tem consists of various measuring instruments that are controlled by GPIB, and covers major part of required perfor- mance test. The test process is divided into three groups according to instruments setup.

  • Page 154: Required Instruments

    Lowpass filter with fc 2 GHz 50 ohms terminator IBM-PC/AT compatible GPIB interface board GPIB-PC2/2A National Instruments Corp. 6.2 Required software Please consult APCS (Anritsu customer service center) for confirmation of software requirements. Performance test software of MS2665C/MS2667C/MS2668C spectrum analyzer.

  • Page 155: Test Group 1

    6769B RF Output 3 dB Power sensor : MA4701A MA4705A (For MS2665C) MA2444A (For MS2667C or MS2668C) Fig. 6-3-1 At the measurement of frequency response, connect the spectrum analyzer’s RF Input to 6769B RF OUTPUT through a signal feeder. The signal feeder consists of a coaxial cable (e.g. SUCOFLEX) less than 1 m length and two 3 dB attenu- ators (41KC-3) attached to each end of the cable.

  • Page 156: Test Group 2

    Section 6 Performance test system 6.4 Test group 2 6.4.1 Test items : Displayed frequency accuracy, Span accuracy, RBW accuracy, selectivity, VBW accuracy, Side band noise at 100 kHz offset, Reference level accuracy, RBW switching error, LOG/Linear scale switching error, Displayed level linearity, Input attenuator switching error, Image response, Multiple response,...

  • Page 157: Test Group 2

    6.4 Test group 2 6.4.2 Setup : The spectrum analyzer RF Input MG3633A MN74A MN63A Output P-ATT 6769B RF Output (1) Use power meter at MN74A’s COM output or 6769B output calibration Power meter : ML4803A or ML2437A Power sensor : MA4701A or MA2444A Fig.

  • Page 158: Test Group 3

    Section 6 Performance test system 6.5 Test group 3 6.5.1 Test items : 2nd harmonic distortion, Two signal 3rd intermodulation distortion, Other spurious responses, IF through, 1 dB gain compression, Local signal leakage, FM demodulation frequency response (option 07), FM demodulation marker display accuracy (option 07).

  • Page 159: Setup

    6.5 Test group 3 6.5.2 Setup : The spectrum analyzer RF Input MG3633A MN74A Output (1) Insert LPFs, at the 2nd 6769B harmonic distortion measurement RF Output Cutoff Frequency : 2 MS2602A RF Input hp11715A SSG2 SSG1 FM/4 AUDIO OUT OUT Termination MA1612A SSG3...
  • Page 160 Section 6 Performance test system On MN74A, connect CH1 to MG3633A OUTPUT, connect CH3 to 6769B RF OUTPUT, and connect CH5 to MS2602A RF Input. Connect MG443B UNBALANCED to 11715A AUDIO IN. On MA1612A, connect SSG3 terminal to MG3633A OUTPUT and terminate SSG2 terminal with 50 ohms terminator. At the measurement, connect the spectrum analyzer’s RF Input to COMMON of MN74A.

  • Page 161: Section 7 Options

    Section 7 Options Introduction ................7.1.1 Option structure summery ..........7.1.2 Retrofit ................Parts, PC board installation ............7.2.1 Cabinet disassembly/assembly ........7.2.2 Parts/PCBs fitting for each option ........7.2.2.1 Option 04 Hi-speed time domain sweep ..7.2.2.2 Option 06 Trigger/gate circuit ......7.2.2.3 Option 07 AM/FM demodulator (voice monitor) ...

  • Page 162: Introduction

    Refer to Fig. 2-3-5 (for MS2665C) or Fig. 3-3-5 (for MS2667/68C). Option 04 High-speed time domain sweep is mounted on A05 SCAN/AD PC board. Refer to Fig. 2-3-5 (for MS2665C) or Fig. 3-3-5 (for MS2667/68C).

  • Page 163: Parts, Pc Board Installation

    7.2 Parts, PC board installation 7.2 Parts, PC board installation 7.2.1 Cabinet disassembly/assembly Fig. 2-3-1 and 2-3-2 (for MS2665C) shows mechanical structure of the instruments (For MS2667/68C, see Fig. 3-3-1 and 3-3-2). To disassemble cabinet, perform procedures below. (1) Remove eight feet.
  • Page 164 (2) For MS2665C, A0901 TRIG/GATE constituent list (34Y106695) For MS2667C or MS2668C, A0901 TRIG/GATE constituent list (34Y106695B) Procedure : Refer to paragraph 2.3.4 (for MS2665C) or paragraph 3.3.4 (for MS2667/68C). (1) Attach A0901-X1 to A09-X3. (2) Fix A0901 to A09 with strut and four screws.

  • Page 165: Option 07 Am/Fm Demodulator (Voice Monitor)

    Related units : (1) A09 OPTION BASE Additional parts: (1) For MS2665C, A09 OPTION BASE constituent list (34Y106684) (not necessary when OPT06 is installed) For MS2667C or MS2668C, A09 OPTION BASE constituent list (34Y106684B) (not necessary when OPT06 is installed)

  • Page 166: Option10 Centronics Interface

    7.2.2.4 Option10 Centronics interface Related units : (1) A03 CPU Additional parts : (1) A04 PMC/CENTRONICS constituent list (34Y106692A or 34Y106692B), refer to paragraph 2.2.1.3 (For MS2665C) or paragraph 3.2.1.3 (For MS2667C) or paragraph 4.2.1.3 (For MS2668C). Procedure : Refer to paragraph 2.3.2.

  • Page 167: Software Setting

    7.3 Software setting 7.3 Software setting Installation consists of four processes, cabinet disassembly, parts/PCB fitting, cabinet assembly, software setting and cali- bration/test. Software setting in Maintenance display is required for options to be effective. Procedure : Entering Maintenance display (1) Turn on power while pushing 0 key. (2) Enter Cal menu by pushing Shift+0 keys.
  • Page 168 Section 7 Options Setting of option (1) Open the second or third page of the Maintenance display. (2) Set option state by using four arrow keys. Fig. 7-3-2 Setting of option...
  • Page 169 7.3 Software setting Saving the state in EEPROM When states of options are changed they must be saved in Flash Memory. (1) Open the fourth page of the Maintenance display. (2) Set cursor on “Save Model & Option Data?” by arrow keys. (3) Push Select (F1) key to enter Save menu.
  • Page 170 Section 7 Options Fig. 7-3-3 Saving the state in Flash Memory 7-10...

  • Page 171: Performance Test

    7.4.1 Option 04 Hi-speed time domain sweep (1) Required equipment : 6769B Swept frequency synthesizer (Anritsu) (2) Specifications : Setting range : 12.5 usec, 25 usec, 50 usec, 100 usec to 900 usec (One most significant digit settable), 1.0 ms to 19 ms (Two upper significant digits settable) Accuracy : ±1%...

  • Page 172: Option 06 Trigger/Gate Circuit

    445.5 usec/454.5 usec 5 msec 4 kHz 4.455 msec/4.545 msec 7.4.2 Option 06 Trigger/gate circuit (1) Required equipment 1) 6769B Swept signal synthesizer (Anritsu) 2) Function Generator (HP3325B) (2) Setup The spectrum analyzer 6769B to Trig/Gate In on the rear...

  • Page 173: Ext Trig Check

    7.4 Performance test (3) Setting 1) Function Generator (HP3325B) Frequency : 100 Hz Function : Square wave Amplitude : 2.5 volts peak to peak Offset : 0 V 2) 6769B Frequency : 100 MHz (CW) Output Level : -10 dBm Pulse External 3) The spectrum analyzer Center frequency : 100 MHz...

  • Page 174: Gate Check

    Section 7 Options 7.4.2.2 GATE Check (1) Set the spectrum analyzer to : Time Span, 20 ms Gate sweep, ON Gate Display, 1 ms Gate Length, 2 ms Gate End, Int (2) Measurement A wave-form like the one shown in View Fig. 7-4-2 should be displayed. 2 ms 1 ms Fig.

  • Page 175: Wide If Video Trig Check

    7.4 Performance test 7.4.2.4 Wide IF Video Trig Check (1) Specification Trig Level High : Approximately -5 to -10 dBm Trig Level Middle : Approximately -15 to -20 dBm Trig Level Low : Approximately -25 to -30 dBm (2) Set the spectrum analyzer to : Trigger Source Wide IF VIDEO Wide IF Trig Level High (3) Measurement...

  • Page 176: Option 07 Am/Fm Demodulator (Voice Monitor)

    AM >1.3 V peak to peak FM (Narrow) >1.3 V peak to peak FM (Wide) >1.3 V peak to peak (2) Required instruments : 1) MG3633A Synthesized signal generator (Anritsu), 2) 8Ω terminator, 3) an earphone plug, 4) an oscilloscope.

  • Page 177: Measure Of Am Voice Monitor Voltage

    7.4 Performance test 7.4.3.1 Measure of AM Voice Monitor Voltage (1) Set the MG3633A output to : Frequency, 1 GHz Level, -10 dBm AM, 30% AF, 1 kHz Set the spectrum analyzer to : Center frequency, 1 GHz Span, 0 Hz RBW, 10 kHz Sound, AM Volume, 20...
  • Page 178 Section 7 Options 7.4.3.3 Measure of FM Voice Monitor Voltage (Wide Band) (1) Set the MG3633A output to FM 75 kHz. Set the spectrum analyzer to : RBW, 300 kHz Volume, 20 (2) Measurement Make sure that sound is heard from the internal speaker. Make sure that the volume is turned up or down by changing the setting.

This manual is also suitable for:

Ms2667cMs2668c

Table of Contents