Kenwood SG-7200 Service Manual
Kenwood SG-7200 Service Manual

Kenwood SG-7200 Service Manual

Signal generator

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SIGNAL GENERATOR
SG-7200/SG-7130
SERVICE MANUAL
FRONT PANEL
PUSH SWITCH
(SG-7200; A63-0192-02)
(S40-2532-05)
(SG-7130; A63-0193-02)
ADDRESS
POWER
STAND BY
STO
HI
1k
(OPT)
LO
EXT
ON /
OFF
VARI
(OPT)
MEMORY
1kHz
RCL
1.75MHz
STO
SHIFT
NEXT
EXT. MOD
DUMP
FM
RTM
ON
3Vp-p/10k‰
KNOB SET(1 assembly)
(K27-3650-04)
RUBBER FOOT; REAR
(J02-0535-03)
RUBBER FOOT; BOTTOM
(J02-0519-05)
MODULATION
SOURCE
FM AM
kHz
F
%
VARI
kHz
(OPT)
GHz
MODULATION
DC-FM
7
8
9
FREQ
EXT
3.5kHz
VARI(OPT)
22.5kHz
SPCL
FM-FM
LEVEL
4
5
6
STEP
1
30%
FM
2
3
AM
.
-
0
ON
AM
REFERENCE
HIGH STABILITY(OPT)
OUTPUT
INPUT
ADJ
HOLE CAP
(F19-1550-05)
KENWOOD TMI CORPORATION
© 2002-9 PRINTED IN KOREA
B51-1163-00 (K-K) PDF
FRAME
(A13-2208-02)
FREQUENCY
dB
OFFSET
REV
MHz
kHz
DATA ENTRY
FREQ
GHz
F
dBm
+ -
MHz
dBµ
kHz
%
EMF dBµ
BS
KNOB
(K21-0951-03)
AC
FUSE
AC INPUT
90-250V
10MHz
TIA
50/60Hz
OUTPUT
38W
TERMINAL
(E21-0667-05)
SG
7200
SIGNAL GENERATOR
OUTPUT
LEVEL
0.1- 2000MHz
dBm
dBµ
EMF dBµ
REMOTE
OUTPUT LEVEL
LOCAL
dB
RF OFF
OUTPUT
REV.POWER
MAX 25W
Z=50Ω
MAX 25V DC
FRAME
(A13-2208-02)
FRAME; SIDE
(A13-2209-02)
REMOTE
GP-IB
SERIAL

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Summary of Contents for Kenwood SG-7200

  • Page 1 SIGNAL GENERATOR SG-7200/SG-7130 KENWOOD TMI CORPORATION SERVICE MANUAL © 2002-9 PRINTED IN KOREA B51-1163-00 (K-K) PDF FRONT PANEL PUSH SWITCH (SG-7200; A63-0192-02) FRAME (S40-2532-05) (SG-7130; A63-0193-02) (A13-2208-02) 7200 SIGNAL GENERATOR ADDRESS MODULATION FREQUENCY OUTPUT LEVEL 0.1- 2000MHz POWER SOURCE FM AM...
  • Page 2: Table Of Contents

    SG-7200/SG-7130 WARNING The following instructions are for use by qualified personnel only. To avoid electric shock, do not perform any servicing other than contained in the operating instructions unless you are qualified to do so. CONTENTS SPECIFICATIONS ......................3 SAFETY ..........................7 BLOCK DIAGRAM ......................8...
  • Page 3: Specifications

    SG-7200/SG-7130 SPECIFICATIONS The following sections mainly describe the operations and functions and functions of the SG-7200. The operations, functions, etc. of the SG-7130 are enclosed in braces, [ ITEMS SG-7200 SG-7130 FREQUENCY Frequency Range 100 kHz to 2 GHz 100 kHz to 1.3 GHz <...
  • Page 4 SG-7200/SG-7130 SPECIFICATIONS ITEMS SG-7200 SG-7130 < = VSWR 1.3 or less at fc 1 GHz > 1.8 or less at fc 1 GHz (A t th e output level of -13 dBm) Protection against reverse power 25 W maximum, 25 VDC...
  • Page 5 SG-7200/SG-7130 SPECIFICATIONS ITEMS SG-7200 SG-7130 Table 5-1 Range Frequency deviation 0 to 9.99 kHz 10 to 99.9 kHz 100 to 250 kHz < = < = 100 kHz 127.5 MHz Resolution 10 Hz 100 Hz 1 kHz Frequency deviation 0 to 9.99 kHz 10 to 60 kHz <...
  • Page 6 10 points x 10, or continuous 100 points Backup functions is provided Memory dumping Transferring stored 100-point data to another SG-7200 or SG-7130(same type) Remote control Same controls as available on the front panel, except turning on and off the power.
  • Page 7: Safety

    SG-7200/SG-7130 SAFETY SAFETY Line fuse Before connecting the instrument to a power source, The fuse holder is located on the rear panel and contains carefully read the following information, then verify that the line fuse. Verify that the proper fuse is installed by the proper power cord is used and the proper line fuse is replacing the line fuse.
  • Page 9: Block Diagram

    SG-7200/SG-7130 BLOCK DIAGRAM GENERATOR UNIT (X71-1250-00) SIGNAL PROCESSOR UNIT (X79-1260-00)
  • Page 10 SG-7200/SG-7130 BLOCK DIAGRAM SIGNAL PROCESSOR UNIT (X79-1270-00) 1kHz CONVERTER UNIT (X78-1190-00) 50MHz...
  • Page 11 SIGNAL PROCESSOR UNIT (X79- 1280- 00) SHIFT SAMPLER GENERATOR REGISTER TRAP AC PATH SPURIAUS ELIMINATION...
  • Page 12 SG-7200/SG-7130 BLOCK DIAGRAM OSCILLATOR UNIT (X71-1260-00) BAND BAND BUFFER CIRCUIT BAND BAND BAND BAND AMP UNIT (X73-2100-00)
  • Page 13 SG-7200/SG-7130 BLOCK DIAGRAM CONVERTER UNIT (X78-1180-00) MODULATOR UNIT (X76-1540-00)
  • Page 14: Adjustment

    1. PREPARATION 1) Be s ure to use a 3P cable with a grounding terminal to supply AC power to the SG-7200. 2) Set the GP-IB address to 7. (Press the SHIFT and LOCAL keys, and the address is displayed on the OUTPUT LEVEL LED indicator.)
  • Page 15 SG-7200/SG-7130 ADJUSTMENT 2. MODULATION UNIT (X76-1540-00) Screw the AF board to the RF case. 1) Internal OSC level adjustment and frequency check Adjustment Frequency Frequency Test point Level position check ± 2 % 1 kHz TP1(OSC OUT) 3.2 Vrms ± 2 %...
  • Page 16 SG-7200/SG-7130 ADJUSTMENT 2) Connection Oscilloscope Digital multi-meter 1 msec/div D C V 5 V/div DC coupling TO REF GEN (D7 Pin3) POWE R METER TO PLL • Connect a 10 MHz, 0 dBm signal source (signal generator) with the REF INPUT connector on the rear panel.
  • Page 17 • Setting of the function generator Input the output signal to the MOD INPUT connector of the SG-7200. Adjust the output level to the point where the HI-LO lamp on the SG-7200 goes out at the sinusoidal wave frequency of 500 Hz.
  • Page 18 SG-7200/SG-7130 ADJUSTMENT • Adjustment using the oscilloscope Triangle wave Rectangular wave (Dev-DC: Correction value) (DC-REF: Correction value) (Dev-DC: Correction value) • • • • • • Fig. 1 Fig. 2 Fig 3 • Input a triangle wave. Adjust R96 so that the waveform shown in Fig. 1 changes into that shown in Fig. 2.
  • Page 19 SG-7200/SG-7130 ADJUSTMENT 8. SIGNAL PROCESSOR UNIT (X79-1280-00) The (upper) VCO case has been attached in the operation test. 1) Adjustment of the notch filters (The notch filters have been set in the operation test.) • Connect the spectrum analyzer with TP2 and tracking generator with TP3.
  • Page 20 SG-7200/SG-7130 ADJUSTMENT • Set the panel frequency to 740 MHz. While turning on and off the PUSH LOCK button of the jig, adjust R79 (GAIN) so that UHF is locked at the center voltage of the saw-tooth wave. (Pressing the button locks UHF.) •...
  • Page 21 • Set the 8902A to FM, PEAK+, 50 Hz HPF, and 15 kHz LPF. Connect it with the output connector. • Set the output of the 8903A to 1 kHz, 0.747 V. Connect it with EXT MOD of the SG-7200.
  • Page 22 SG-7200/SG-7130 ADJUSTMENT 7) Final setting After collecting data for the test report, carry out production reset. Product reset 1. Set the DIP switches on the CPU board as shown in Fig. 1. 1 ON 2 ON 3 ON 4 ON...
  • Page 23 Teile ohne Parts No. werden nicht geliefert. Teile ohne Parts No. werden nicht geliefert. Ref. No Parts No. Name & Description Ref. No Parts No. Name & Description SG-7200 (Y76-1030-00) SG-7130 (Y76-1030-01) J32-0865-04 BOSS (L=10MM/M3) J30-0654-04 SPACER A01-4024-12 CASE; TOP J31-0635-05...
  • Page 24 ✽ New Parts Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No. werden nicht geliefert. Ref. No Parts No. Name & Description X73-2100-00 AMP UNIT X73-2110-00 AMP UNIT X75-1230-00 ATTENUATOR UNIT...
  • Page 25 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 26 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 27 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 28 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 29 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 30 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 31 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 32 ✽ New Parts New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 33 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 34 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 35 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 36 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 37 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 38 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 39 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 40 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. & Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 41 ✽ New Parts Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No. werden nicht geliefert. Ref. No Parts No. Name & Description E23-1512-05 TEST TERMINAL E23-1512-05 TEST TERMINAL E23-1512-05 TEST TERMINAL...
  • Page 42 Teile ohne Parts No. werden nicht geliefert. Teile ohne Parts No. werden nicht geliefert. Ref. No Parts No. Name & Description Ref. No Parts No. Name & Description CPU UNIT (X77-1970-00/SG-7200)(X77-1970-01/SG-7130) CC73FCH1H331JM CAP. CHIP (2✽1.25) 330p CC73FCH1H331JM CAP. CHIP (2✽1.25) 330p CC73FCH1H331JM CAP.
  • Page 43 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 44 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 45 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 46 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 47 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 48 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 49 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 50 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 51 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 52 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. & Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 53 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 54 ✽ New Parts ✽ New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. ¡ ™ Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
  • Page 55: Schematic Diagram

    SCHEMATIC DIAGRAM E04-0286-05 E04-0286-05 E38-1130-15 E38-1131-15 E38-1143-15 E38-1198-05 E38-1198-05 E38-1197-05 E38-1197-05 E38-1200-05 E38-1202-05 E38-1203-05 E38-1201-05 E38-1198-05 E38-1199-05 E38-1201-05 E38-1201-05 E38-1140-15 E38-1204-15 E38+1125-05 (E38-1125-05) SG-7200/SG-7130...
  • Page 56 SG-7200/SG-7130...
  • Page 57 SG-7200/SG-7130...
  • Page 58 SG-7200/SG-7130...
  • Page 59 SG-7200/SG-7130...
  • Page 60 SG-7200/SG-7130...
  • Page 61 SG-7200/SG-7130...
  • Page 62 SG-7200/SG-7130...
  • Page 63 SG-7200/SG-7130...
  • Page 64 SG-7200/SG-7130...
  • Page 65 SG-7200/SG-7130...
  • Page 66 SG-7200/SG-7130...
  • Page 67 SG-7200/SG-7130...
  • Page 68 SG-7200/SG-7130...
  • Page 69 SG-7200/SG-7130...
  • Page 70 SG-7200/SG-7130...
  • Page 71 SG-7200/SG-7130...
  • Page 73 SG-7200/SG-7130...
  • Page 74 SG-7200/SG-7130...
  • Page 75 SG-7200/SG-7130...
  • Page 76 SG-7200/SG-7130...
  • Page 77 (1-D2) (1-C2) (1-C5) (1-B5) (1-B5) (1-A5) (3-C5) (1-D7) (3-B4) (1-A3) (5-C5) (5-C5) (5-C5) (5-C5) (5-C5) (5-C5) (5-C2) (5-C2) (5-C2) (5-C2) (5-C2) (1-C2) SG-7200/SG-7130...
  • Page 78 (5-B2) (5-B5) (5-B5) (5-B2) (5-B2) (1-C2) (5-B5) (1-D3) (1-D3) (1-D3) (5-B5) (1-D3) (1-C5) (1-B5) (5-B2) (5-B5) (1-A2) (5-B5) (1-C5) (1-B5) SG-7200/SG-7130...
  • Page 79 (4-B7) (4-A7) (4-A7) (4-B7) (4-A4) (1-C2) (4-A4) (4-C7) (4-A3) (1-D3) (1-D3) (4-C7) (4-C7) (3-C3) (3-C3) (3-D3) (3-C3) (3-D3) (3-C3) (3-D3) (3-C3) (3-D3) (3-C3) (3-D3) (4-B4) (4-B4) (2-B4) (2-B4) (2-B5) (2-B4) (2-B4) (2-B4) (2-B5) (2-B4) SG-7200/SG-7130...
  • Page 80 OR39 OR39 R53 33 120u 120u RN2403 SG-7200/SG-7130...
  • Page 81 500MHz IN TO DOWN CONV.-1 800MHz OUT 690~740MHz OUT RN1403 60~110MHz IN SG-7200/SG-7130...
  • Page 82 FROM OUTPUT AMP-2 130MHz-2GHz IN...
  • Page 83 C114 104 HC00 HC74 RN2403 RN2403 RN1403 SG-7200/SG-7130...
  • Page 84 SG-7200/SG-7130...
  • Page 85 50MHz IN DC TUNE OUT 690~740MHz IN 1~2GHz IN RN1403 SG-7200/SG-7130...
  • Page 86 PC BOARD(Component side view) PANEL UNIT(X66-1440-00) Parts side view DISPLAY UNIT(X66-1450-00) Parts side view DISPLAY UNIT(X66-1450-00 S/No.7050001~) Parts side view Refer to the schematic diagram for the value of resistors and capacitors.
  • Page 87 PC BOARD(Component side view) MOTHER BOARD UNIT (X67-1270-00) A/2 Parts side view CONNECTION UNIT (X67-1260-00) CONNECTION UNIT (X67-1360-0X) Parts side view Parts side view POWER SUPPLY UNIT (X68-1780-00) CONNECTION UNIT (X67-1280-00) A/3 Parts side view Parts side view Pattern side view B/3 POWER SUPPLY UNIT (X68-1790-00) Parts side view Pattern side view C/3...
  • Page 88 PC BOARD (Component side view) GENERATOR UNIT (X71-1250-00) Parts side view RF frequency FREQ STD FINE ADJ fine control OSCILLATOR UNIT (X71-1260-00) Parts side view OUTPUT UNIT (X72-1220-00) Parts side view AMP UNIT (X73-2100-00) Bias Parts side view Linearity Refer to the schematic diagram for the value of resistors and capacitors.
  • Page 89 PC BOARD (Component side view) AMP UNIT (X73-2110-00) Parts side view level adjustment and check ATTENUATOR UNIT (X75-1230-00) Parts side view MODULATION UNIT (X76-1540-00) Parts side (Parts side view) OFFSET 2 2 TONE H/L LVL OSC LVL OFFSET 1 OFFSET 3 Pattern side ( Pattern side view) AM modulation level...
  • Page 90 CPU UNIT (X77-1970-00/SG-7200 X77-1970-01/SG-7130) Parts side view...
  • Page 91 PC BOARD (Component side view) CONVERTER UNIT (X78-1180-00) Parts side view 120MHz Down converter Down converter 100MHz flatness RF level CONVERTER UNIT (X78-1190-00) Parts side view peak peak CONVERTER UNIT (X78-1200-00) Parts side view Refer to the schematic diagram for the value of resistors and capacitors.
  • Page 92 PC BOARD (Component side view) SIGNAL PROCESSOR UNIT (X79-1260-00) Parts side view FINE SYNTHE TRACKING SCAN SIGNAL PROCESSOR UNIT (X79-1270-00) Parts side view DEV-DC DC • FM FREQ DC • FM ON/OFF FM DIST BIAS SCAN ADJ HF SUMMING LOOP DC-REF SIGNAL PROCESSOR UNIT (X79-1280-00) Parts side view...
  • Page 93 SG-7200/SG-7130 A product of KENWOOD TMI CORPORATION 1-16-2, HAKUSAN, MIDORI-KU, YOKOHAMA CITY 226-8525, JAPAN...

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