Watkins Johnson WJ-87 18-17 User manual

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INSTRUCTION MANUAL
FOR
WJ-8718-17 HF RECEIVER
The \\'J-8ilS-17 I.qstruction 11anual supplements
the \\'J -8718 HF Receiver Instruction 1\Ianual and
the WJ -8718/1\1 FP Option Instruction lIanual and
is to be used in conjunction with those manuals.
This document and subject matter disclosed
herein are proprietary items to which \\'atkins-
Johnson Company retains the exclusiYe right of
dissemination, reproduction, manufacture and
sale.
This document is provided to the indiYidual or
using organization for their use alone in the direct
support of the associated equipment unless per-:
mission for further disclosure is expressly
granted in writing.
WATKINS-JOHNSON COMPANY
700 QUINCE ORCHARD ROAD
GAITHERSBURG,MARYLAND 20760
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WJ-8718-17
GENERAL DESCRIPTION
SUPPLEMENT
The
WJ-8718-17 is amodified version of the standard WJ-8718 HF Receiver. It
includes, as standard equipment, a Microprocessor Front Panel Option (WJ-8718/MFP), and
incorporates all the regular features and reliability of the standard W J-8718 Receiver and
MFP Option,
with the added features of scan interrupt capability and a slower scan time.
Modifications have been made to both the standard WJ-8718 main chassis and the
WJ-8718/MFP circuitry. The information contained in this section is supplemental to both the
WJ-8718 Instruction Manual and the WJ-8718/MFP Instruction Manual.
OPERATION
When
operated in scan mode the WJ-8718-17 scans the selected memory channels
as a rate of approximately 100 msec per channel. Scanning may be interrupted at any time by
applying
+5 V to the SCAN STOP input J14 located on the rear panel of the receiver. The
receiver will continue to operate in the fixed mode selected by the memory channel being
scanned at the time of interrupt. When the level at J14 returns to a V the receiver will
resume scanning automatically.
CIRCUIT DESCRIPTION
The SCAN STOP line is
routed from rear panel jack J14 to pin Ala of IF Interface
MFP-A3, and from there to the previously unused serial data input of the microprocessor (U1,
pin
5) on MFP-A3.
The software associated with U25 and U26 of Synthesizer Interface MFP-A4 has
been modified to include a program step (during scanning operation) in which the DC voltage
level at U1 pin 5is detected. If a level of a Vdc (TTL "low") is detected at pin 5scanning is
not interrupted. If a level level of +5 V(TTL Ilhigh
ll
)is detected at pin 5 the receiver stops
scanning and continues to operate in mode selected by the memory channel presently being
scanned. The processor continues to look at pin 5 periodically during its regular program cycle
and when a return to a V is detected the receiver continues the previously interrupted scan
operation.
The software of U25 and U26 of the Synthesizer Interface has also been modified
in
order to change the scan time from 50 msec to 100 msec per memory channel.
REPLACEMENT PARTS LIST
The following
changes should be made to the Replacement Parts List sections of
the WJ-8718 HF Receiver and WJ-8718/MFP Option Instruction Manuals.
The Main Chassis
Parts List (paragraph 5.5 of WJ-8718 Instruction Manual) should
have
added: REF DESIG J14, Same as J12. The QTY. PER ASSY for REF DESIG Jll should be
changed from 2 to 3.
The
listings for ICs U25 and U26 on the Synthesizer Interface Parts List
(paragraph 1.14.4 of the MFP Manual) are unchanged. It should be noted however that when
ordering replacement ICs SCAN STOP software should be specified.
1
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INSTRUCTION MANUAL
FOR
WJ-8718 HF RECEIVER
This document and subject matter disclosed herein are proprietary
items to which Watkins-Johnson Company retains the exclusive
right of dissemination, reproduction, manufacture and sale.
This document is provided to the individual or using organization
for their use alone in the direct support of the associated equipment
unless permission for further disclosure is expressly granted in
writing.
WATKINS-JOHNSON COMPANY
700 QUINCE ORCHARD ROAD
GAITHERSBURG, MARYLAND 20760
Revision V
01/80: 500
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IWARNING I
This equipment employs dangerous voltage which
may be fatal if contacted. Exercise extreme cau-
tion in working with this equipment with any of the
protective covers removed.
I C_A_U_T_I_O_N_I
Leakage of the Nickel-Cadmium battery (A6AlBT1)
supplied with Type 791575 Manual Tuning Up/Down
Counter (A6Al) has been reported, and the probable
causes are being investigated. If the battery is in-
stalled, it should be removed to prevent possible
damage to the equipment from corrosion.
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WJ-8718 HF RECEIVER
TABLE OF CONTENTS
SECTION I
GENERAL DESCRIPTION
CONTENTS
Paragraph
1.1
1.2
1.3
1.4
1.5
2.1
2.2
2.3
2.3.1
2.3.2
2.3.3
2.3.4
2.3.5
2.3.6
2.3.7
2.3.8
2.3.9
2.3.10
2.3.11
2.4
2.4.1
2.4.2
2.4.3
2.4.4
2.4.5
2.4.6
2.4.7
2.4.8
2.4.9
2.4.10
2.4.11
3.1
3.1.1
3.2
Electrical Characteristics. .
Mechancial Characteristics • .
Equipment Supplied
Equipment Required But Not Supplied.
Optional Equipment . . . . . . . . .
SECTION II
INSTALLATION AND OPERATION
Unpacking and Inspection . . . • . . . • . . . . . . . . •
Preparation For Reshipment and Storage . . • . . . . . . .
Inst alIa ti on . . . . . . . . . . . . . . . . . . . • . . .
Voltage Selector/Fuse Block and Line Card Receptacle (F1J1) .
RF Input (A2J1) . . • . .
Alternate Fuseholder (XF2) .
IF
Output (J12) . • .
Terminal Board (TB1) .
Terminal Board (TB2) .
Line Audio Level (R1)
Clock Switch (S2) ...
1MHz
Ref (Jll). . .
Phones Jack (J13) . .• •
Remote Input Option (A6A1J1).
Operation. . . • . . . .
Push On/Off Power (Sl). •
Meter (M1) ...
Meter Switches .
Gain Mode ..•
RF Gain Control.
Detection Mode . .
IF
Bandwidth (kHz). . • . •
BFO
Offset. . . . .
Tuned Frequency Readout.
Manual Tuning Module (A 7) . .
Phone Level Control . .
General. . • • . .
Overall Description
Receiver Section. . .
Page
1-1
1-2
1-2
1-3
1-3
2-1
2-1
2-1
2-3
2-3
2-3
2-3
2-3
2-4
2-4
2-4
2-4
2-4
2-4
2-6
2-6
2-6
2-6
2-6
2-7
2-7
2-8
2-8
2-8
2-8
2-9
3-1
3-1
3-1
iii
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CONTENTS
Paragraph
WJ-8718 HF RECEIVER
TABLE
OF CONTENTS (Cont'd)
SECTION III
CIRCUIT DESCRIPTION
3.2.1
3.2.2
3.2.2a
3.2.3
3.2.4
3.2.5
3.2.5a
3.2.6
3.2.7
3.2.8
3.2.8a
3.2.9
3.2.9a
3.2.10
3.2.11
3.2.12
3.2.13
3.2.14
3.3
3.3.1
3.3.2
3.3.2.1
3.3.2.2
3.3.2.3
3.3.2.4
3.3.3
3.3.3.1
3.3.3.2
3.3.4
3.3.4.1
3.3.4.2
3.3.5
3.3.5.1
3.3.5.2
3.3.6.
3.3.6.1
3.3.6.2
3.3.7
3.3.7.1
3.3.7.2
3.3.7.2.1
3.3.7.2.2
iv
Functional Description • . . . .
Type 791616 RF Filter (A2) . . .
Type 791616 RF Input Filter (A2).
Type 791592 Input Converter (A3)
Type 791569 IF Motherboard (A4)
Type 791594 10.7 MHz Filter Switch (A4A1). .
Type 791594 10.7 MHz
Filter Switch (A4A1) (Revision E) .
Type 71430 10.7 MHz/455 kHz Converter (A4A2). • • .
Type 791595 455 kHz Filter Switch (A4A3) . . . . . .
Type 791596 USB Filter Switch Option (A4A4) . . . . . .
Type 791596 USB Filter Switch Option (A4A4) (Revision G) . • . . .
Type 791597 ISB/LSB Filter Switch Option (A4A5) . . • • . .
Type 791597 ISB/LSB Filter Switch Option (A4A5) (Revision E) .
Type 72488 455 kHz Amplifier/AM Detector (A4A7)
Type 78112 AGC (A4A6) • . . . . . . . . .
Type 791599 FM/CW/SSB
Detector (A4A9) . .
Type 7459 Audio
Amplifier (A4A10) .....
Type 791598 ISB Detector/Audio Option (A4A8)
Synthesizer Section • . . . . • . . • • .
Synthesizer Relationships. . . . . .
Phase Lock Loops .....
General. . • . . . . . .
Basic Phase Lock Loop . . . . . .
Phase Lock Loop Pre scaling Technique. .•.•.•.•
Phase Detector • . . . . . . . . . .
Type 791600 Time Base Circuits (A5A1A2)
Functional Description . • . . . . . . .
Circuit Description. ...........
Type 791600 3rd LO Synthesizer (A5A1A2)
Functional Description . . • . . . • .
Circui t Description. • . . • . • . • .
Type 791576 BFO Synthesizer (A5A3). . •
Functional Description . . . • • . . •
Circui t Description. • . . . . . . . .
Type 791601 2nd LO Synthesizer (A5A2).
Functional Description . . . . • . • .
Circuit Description. . • . . . . • . . .
Type 791600 1st LO Synthesizer (A5A1A2) .
Functional Description
Circui t Description. .
Counting Cycle ...
Prescaler, U1 and U2A
3-1
3-3
3-3a
3-3
3-4
3-4
3-4a
3-5
3-5
3-6
· 3-6a
3-6
• 3-6a
3-7
3-7
3-10
3-11
3-12
· 3-15
· 3-15
· 3-16
. • 3-16
3-18
3-19
3-20
3-22
·
3-22
· 3-22
3-24
3-24
3-25
· 3-25
• 3-25
3-25
3-28
3-28
3-29
3-31
3-31
·
3-33
• 3-33
· 3-34
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WJ-8718 HF RECEIVER
TABLE
OF CONTENTS (Cont'd)
SECTION III (Concluded)
CIRCUIT DESCRIPTION (Concluded)
CONTENTS
Paragraph
3.3.7.2.3
3.3.7.2.4
3.3.7.2.5
3.3.7.2.6
3.3.7.2.7
3.3.7.2.8
3.3.7.3
3.3.8
3.3.8.1
3.3.8.2
3.3.9
3.4
3.4.1
3.4.1.1
3.4.1.2
3.4.2
3.4.3
3.4.4
3.4.5
3.4.6
3.4.7
3.4.8
3.4.9
3.4.10
3.5
3.5.1
3.5.2
4.1
4.2
4.2.1
4.2.2
4.3
4.4
4.5
4.5.1
Digital Code Converter U4 .
Programmable Counter U9, U10, un. .
Swallow Counter U8 and U9. .
Carry Condition U12A and U6B
Count Sequence . . . . • . .
Divider Section Terminal Count .
VCO Band
Select Code . . . . . . . . . . . . .
Type 791629 Voltage Controlled Oscillator (A5A1A1) .
Functional Description . . • . . . . . . . . . .
Circuit Description. ...•..............
Type 791630 1st and 3rd LO Synthesizer/Time Base (A5A1).
Digi tal Control Section. . . . . . . . . . . . . . •
Type 791575-2 Manual Tuning Up/Down Counter (A6A1).
Integrated Circuit Data. . . . . . . . . . .
Circuit Description. ...........
Type 791828
Front Panel Interconnect (A6A2)
Type 791874-1 Manual Tuning Module (A7).
Type 791589 Tuning Resolution (A7A1)
Encoder Assembly (A 7U1). • . . . .
Type 791578 Frequency pisp~ay (A8) •
Type 791588 BFO Switch (A9) .....
Type 791684 Front Panel Control (A10)
Type 791583 Upper Panel Control (A10A!). .
Type 791826 Lower Panel Control (A10A2)
Power Supply Section. ......
Type 76240 Power Distribution (A1)
Power Supply RegUlators . . • . . .
SECTION
IV
MAINTENANCE
General. • . . . . . .
Cleaning and Lubrication .
Cleaning . . . . . . •
Lubrica tion . . . . . • •
Inspection for Damage or Wear
Test Equipment Required . . .
Corrective Maintenance Information
General. .............
Page
3-35
· 3-36
3-36
· 3-36
3-36
3-39
3-40
3-40
3-40
·3-41
3-42
· 3-42
· 3-42
· 3-42
3-45
3-46
3-48
3-48
3-49
3-50
· 3-50
· 3-51
3-51
·3-51
·3-51
3-52
3-52
4-1
4-1
4-1
4-2
4-3
4-3
4-3
4-3
v
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CONTENTS
Paragraph
WJ-8718 HF RECEIVER
TABLE OF CONTENTS
(Cont'd)
SECTION IV (Cont'd)
MAINTENANCE (Cont'd)
4.5.2
4.6
4.6.1
4.6.2
4.6.3
4.6.4
4.6.5
4.6.6
4.6.7
4.6.8
4.6.9
4.7
4.7.1
4.7.2
4.7.3
4.7.3.1
4.7.3.2
4.7.4
4.7A.1
4.7.4.2
4.7.5
4.7.5.1
4.7.5.2
4.7.6
4.7.6.1
4.7.6.2
4.7.6.2a
4.7.7
4.7.7.1
4.7.7.2
4.7.8
4.7.8.1
4.7.8.2
4.7.9
4.7.9.1
4.7.9.2
4.7.9.2a
4.7.10
4.7.10.1
4.7.10.2
4.7.10.2a
4.7.11
vi
Procedure Guidelines. .
Performance Tests. . .
General. . . . . . •
Minimum
Performance Standards.
Procedure Guidelines. .. • • •
Operator Performance Test . • . .
IF
Gain and Bandwidth Performance Test
SIN Ratio Performance Test. • . .
Detection Mode Performance Test . .
MAN/AGC
Performance Test .....
Frequency Tuning Performance Test .
Component Level Troubleshooting Procedures •
General. . . . • . • . • . . . . . . .
Procedure Guidelines. . • . . . . • . .
Power Supply Testing and Troubleshooting. .
Power Supply Checkout Procedure . •
Power Supply Fault Isolation. . . . . .
RF Filter Testing and Troubleshooting
RF Filter Checkout Procedure. . . .
RF Filter Fault Isolation • • • . . • •
Input
Converter Testing and Troubleshooting.
Input Converter Checkout Procedure • • • .
Input
Converter Fault Isolation . . . • . .
10.7 MHz
Filter Switch Testing and Troubleshooting
10.7 MHz Filter Switch Checkout Procedure. • . • .
10.7 MHz
Filter Switch Fault Isolation • • • • • • •
10.7 MHz
Filter Switch Fault Isolation (Revision E). •
10.7
MHz/455 kHz Converter Testing and Troubleshooting. •
10.7
MHz/455 kHz Converter Checkout Procedure •
10.7
MHz/455 kHz Converter Fault Isolation. • •
455
kHz Filter Switch Testing and Troubleshooting •
455
kHz Filter Switch Checkout Procedure • • .
455
kHz Filter Switch Fault Isolation. • . . . .
USB
Filter Switch Testing and Troubleshooting. • • • • • .
USB
Filter Switch Checkout Procedure . . .
USB
Filter Switch Fault Isolation .•..•...
USB Filter Switch Fault Isolation (Revision G) • .
ISB/LSB
Filter Switch Testing and Troubleshooting • • . . .
ISB/LSB
Filter Switch Checkout Procedure • . . .
ISB/LSB
Filter Switch Fault Isolation. • . . . .
ISB/LSB
Filter Switch Fault Isolation (Revision E)
455 kHz Amplifier/AM Detector Testing and Troubleshooting
4-5
4-5
4-5
4-5
4-6
4-13
4-13
·4-15
•4-16
·4-19
. . . . . 4-20
· . 4-33
4-33
4-33
· . • 4-33
·4-33
4-34
4-34
•4-34
. . . . . 4-35
·4-35
•4-35
·4-36
· • 4-37
·4-37
·4-38
· .
.4-38a
•4-38
·
4-39
·4-39
4-40
· . • 4-40
· . 4-40
•4-41
•4-42
•4-42
· .
.4-42a
·4-43
·4-43
· .
4-44
• .4-44a
• • 4-44
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WJ-8718 HF RECEIVER
TABLE
OF CONTENTS (Cont'd)
SECTION IV (Cont'd)
MAINTENANCE
(Cont'd)
Paragraph
CONTENTS
4.7.11.1
4.7.11.2
4.7.12
4.7.12.1
4.7.12.2
4.7.12.3
4.7.13
4.7.13.1
4.7.13.2
4.7.14
4.7.14.1
4.7.14.2
4.7.15
4.7.15.1
4.7.15.2
4.7.16
4.7.16.1
4.7.16.2
4.7.17
4.7.17.1
4.7.17.2
4.7.18
4.7.18.1
4.7.18.2
4.7.18.3
4.7.19
4.7.19.1
4.7.19.2
4.7.19.3
4.7.20
4.7.20.1
4.7.20.2
4.7.20.3
4.7.21
4.7.21.1
4.7.21.2
4.7.21.3
4.7.22
4.7.22.1
4.7.22.2
4.7.22.3
4.7.23
455
kHz Amplifier/AM Detector Checkout Procedure. .
455kHz Amplifier/AM Detector Fault Isolation . . . • . .
FM/CW/SSB
Detector Testing and Troubleshooting . .
CW /SSB Detector Checkout Procedure . . . .
FM Detector Checkout Procedure .....
FM/CW/SSB
Detector Fault Isolation. • • .
Audio
Amplifier Testing and Troubleshooting
Audio Amplifier Checkout Procedure. . . . .
Audio
Amplifier Fault Isolation . . . . . •
ISB Detector/Audio Testing and Troubleshooting . . . . •
ISB
Detector /Audio Checkout Procedure
ISB Detector /Audio Fault Isolation .
AGC
Testing and Troubleshooting . . .
AGC
Checkout Procedure. . . . • . . .
AGC
Fault Isolation . . . . . . . . . .
Front Panel Interconnect Testing and Troubleshooting. .
Front Panel Interconnect Checkout Procedure . .
Front Panel Interconnect Fault Isolation . . . .
Lower
Panel Control Testing and Troubleshooting
Lower Panel Control Checkout Procedure. . .
Lower
Panel Control Fault Isolation . . . . .
1st LO Synthesizer Testing and Troubleshooting
1st LO Synthesizer Checkout Procedure. . . • .
1st LO Synthesizer Fault Isolation • . . • . • .
1st LO Synthesizer Supplementary Troubleshooting Data
2nd LO Synthesizer Testing and Troubleshooting • . . . •
2nd LO
Synthesizer Checkout Procedure . . . . . . . .
2nd LO
Synthesizer Fault Isolation . . . . . • . • . •
2nd LO
Synthesizer Supplementary Troubleshooting Data
3rd LO Synthesizer Testing and Troubleshooting • . . • . • • • •
3rd LO
Synthesizer Checkout Procedure. . . . . • • .
3rd LO
Synthesizer Fault Isolation . • . . . • • • • • . . • . •
3rd LO
Synthesizer Supplementary Troubleshooting Data
BFO Synthesizer Testing and Troubleshooting .....
BFO
Synthesizer Checkout Procedure. • . . • . . .
BFO
Synthesizer Fault Isolation • • . . . . . • • •
BFO
Synthesizer Supplementary Troubleshooting Data
Time Base Testing and Troubleshooting • . . . .
Time Base Checkout Procedure . • • . . . . .
Time Base Fault Isolation. . . . . • . . . .
Time Base Supplementary Troubleshooting Data .
Parts Replacement Guidelines. .......
4-45
4-45
4-46
•4-46
4-47
·4-47
4-49
•4-49
4-49
4-50
·4-50
· . 4-51
·4-52
·4-52
4-53
4-55
4-55
4-56
•4-56
4-56
· . 4-57
· . 4-57
4-57
4-58
·4-60
· . 4-60
· . 4-60
·4-60
4-63
4-63
·4-64
·4-64
·4-64
· . 4-65
4-65
·4-65
4-67
·4-67
· . 4-67
4-68
4-68
4-68
vii
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CONTENTS
Paragraph
4.7.23.1
4.7.23.2
4.7.23.3
4.8
4.8.1
4.8.2
4.8.2.1
4.8.2.2
4.8.2.3
4.8.2.4
4.8.2.5
4.8.2.6
4.8.3
4.8.3.1
4.8.3.2
4.8.3.2a
4.8.3.3
4.8.3.4
4.8.3.5
4.8.3.5a
4.8.3.6
4.8.3.7
4.8.4
5.1
5.2
5.3
5.4
5.5
5.5.1
5.5.2
5.5.2A
5.5.3
5.5.3.1
5.5.3.2
5.5.3.3
viii
TABLE OF CONTENTS (Cont'd)
SECTION IV (Concluded)
MAINTEN ANCE (Concluded)
Soldering Techniques. . • • . .
Component Replacement • . . .
Realignment . . . . . . • . .
Adjustment/ Alignment Procedures .
General. . . . . . . . . . . .
Synthesizer Alignment . . . . . .
1st LO Synthesizer Alignment • . . .
2nd LO
Synthesizer Alignment (A5A2)
2nd LO
Filter Adjustment. . .
3rd LO Synthesizer Alignment. •
2MHz
Time Base Adjustment
BFO Synthesizer Alignment . . •
Receiver Alignment • . . . . .
Input Converter Alignment . .
10.7 MHz
Filter Switch Adjustment. . • . • . .
10.7 MHz Filter Switch Adjustment (Revision E) .
455
kHz Amplifier/AM Detector Response Alignment.
455 kHz Amplifier/AM Detector Gain Adjustment . . .
USB
Filter Switch and ISB/LSB Filter Switch Adjustment
USB Filter Switch and ISB/LSB Filter Adjustment
ISB Detector/Audio Adjustment .
FM Discriminator Alignment
LED Intensity Adjustment. . .
SECTION V
REPLACEMENT PARTS LIST
Unit Numbering Method. . . .
Reference Designation Prefix
List of Manufacturers
Parts List. • • • • • . • •
Type
WJ-8718 HF Receiver, Main Chassis.
Type 76240 Power Distribution (A1)
Type 791616
RF Filter (A2) • . . • . . .
Part 280093 30 MHz Low Pass Filter (A2A1) • • • •
Type 791592-1
Input Converter (A3) . • . .
Part 34748 1st Mixer, 1st IF (A3A1) .•....
Part 34749 2nd Mixer/2nd IF Amplifier (A3A2)
Part 280080 Filter Board (A3A3). • . . . . .
WJ-8718 HF RECEIVER
·
4-69
·4-69
· . 4-69
4-69
4-69
4-70
4-70
·4-70
4-73
·4-73
·
4-74
• . 4-74
4-74
4-74
4-76
· .4-76a
4-77
• .
4-79
·4-79
.4-80a
·4-80
•4-82
4-84
5-1
5-1
5-1
5-4
5-6
·5-13
5-15
. . .5-15C
• 5-16
5-17
5-19
5-21
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WJ-8718 HF RECEIVER
TABLE OF CONTENTS (Concluded)
SECTION V (Concluded)
REPLACEMENT PARTS LIST (Concluded)
Paragraph
CONTENTS
5.5.4
5.5.4.1
5.5.4.1A
5.5.4.2
5.5.4.3
5.5.4.4
5.5.4.4A
5.5.4.5
5.5.4.5A
5.5.4.6
5.5.4.7
5.5.4.8
5.5.4.9
5.5.4.10
5.5.5
5.5.5.1
5.5.5.1.1
5.5.5.1.1.1
5.5.5.1.2
5.5.5.2
5.5.5.3
5.5.6
5.5.6.1
5.5.6.2
5.5.7
5.5.7.1
5.5.8
5.5.9
5.5.10
5.5.10.1
5.5.10.2
Type 791569 IF Motherboard (A4) . . . . • . . •
Type 791594 10.7 MHz Filter Switch (A4A1) ....
Type 791594 10.7 MHz Filter Switch (A4A1) ...
Type 71430 10.7 MHz/455 kHz Converter (A4A2) • •
Type 791595 455 kHz Filter Switch (A4A3). . • .
Type 791596 USB Filter Switch (A4A4) (Option). .
Type 791596 USB Filter Switch (A4A4). . . . . .
Type 791597 ISB/LSB Filter Switch (A4A5) (Option)
Type 791597 ISB/LSB Filter Switch (A4A5) . . . .
Type 78112 AGC Amplifier (A4A6) . . . . . . . .
Type 72488 455 kHz Amplifier/AM Detector (A4A 7). .
Type 791598 ISB Detector/Audio (A4A8) . • . • • • .
Type 791599 FM, CW, and SSB Detector (A4A9). . •
Type 7459 Audio Amplifier (A4A10) • . . • . . . . .
Type 791570 Synthesizer Motherboard (A5). . . . . . . .
Type 791630 1st and 3rd LO Synthesizer/Time Base (A5A1).
Type 791629 1st LO VCO Assembly (A5A1A1) . • . . • •
Part 34750 1st LO Voltage Controlled Oscillator (A5A1A1A1)
Type 791600 1st and 3rd LO Synthesizer (A5A1A2) • • . .
Type 791601 2nd LO Synthesizer (A5A2). . . • . . .
Type 791576 BFO Synthesizer (A5A3) . . • . • • • .
Type 791580 I/O Motherboard (A6) . . . . . • . . .
Type 791575-2 Manual Tuning Up/Down Counter (A6A1) .
Type 791828 Front Panel Interconnect (A6A2).
Type 791874-1 Manual Tuning Module (A7)
Type 791589 Tuning Resolution (A7 AI) ...••.
Type 791578 Frequency Display (A8). . . •
Type 791827 BFO Switch (A9) ..•.•..
Type 791684-2 Front Panel Control (A10).
Type 791583 Upper Panel Control (A10A1) •
Type 791826 Lower Panel Control (A10A2) .
5-22
· 5-25
.5-27 A
•
5-29
· 5-31
· 5-33
.5-33A
· 5-35
•.. 5-36A
· 5-37
5-39
5-43
• 5-47
5-49
5-52
· 5-55
· 5-57
5-58
5-61
5-67
5-73
5-77
5-79
5-80
5-81
· 5-83
5-85
5-86
5-87
5-88
. • . . • . . 5-89
SECTION VI
SCHEMATIC DIAGRAMS
ix
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CONTENTS WJ-8718 HF RECEIVER
LIST
OF ILLUSTRATIONS
Figure
1-0
2-0
• •
.. 2-2
· . . . .. 2-2
3-0a
3-0b
3-9
3-14
·3-17
·3-18
3-19
3-20
3-21
. . . . . . 3-23
. . • . . . . • 3-23
. • .
.. . 3-24
. • • 3-26
. • •
.. 3-28
3-30
3-32
·
3-34
·3-35
3-39
•3-41
·3-43
·
3-44
. . 3-44
3-47
3-49
4-8
4-10
4-12
·4-15
4-16
4-18
• . • 4-20
· . . • • • 4-21
• •
4-24
· • • • . • 4-24
· 4-24
4-26
·4-26
4-26
·
4-28
. . • • . 4-28
·4-28
·4-30
4-30
WJ-8718 HF Receiver • . • • . . . .
WJ-8718
Receiver, Critical Dimensions.
WJ-8718 HF Receiver, Front Panel View
WJ-8718 HF Receiver, Rear Panel View.
WJ-8718 Overall Block Diagram • • . .
Receiver Section, Functional Block Diagram.
Simplified AGC Circuit. . . • . . . . . .
Frequency Synthesizers Functional Relationships. .
Basic Phase Lock Loop Configura tion. . . . . .
Programmable Phase Lock Loop . . • • . • • •
Two-Modulus
Prescaling in the Phase Lock Loop
Prescaler Dividing Technique . . . • • . • . . • • •
Phase Detector Timing Diagram • • • . • .
Time Base Circuits Functional Block Diagram .
Tri-State Buffers . • . . . . .
3rd
LO Functional Block Diagram
BFO Functional Block Diagram
2nd LO Functional Block Diagram
2nd LO Prescaler Timing Diagram • • . • • • . • . •
1st LO
Functional Block Diagram.
1st LO Counting Cycle • . . . . .
1st LO
Prescaler Timing Diagram. •
Two-Pulse Early Decode, Count Termination •.
VCO Functional Block Diagram . • . . . . . • • • .
Digital Section Functional Block Diagram.. .•.•
Manual Tuning Up/Down Counter Block Diagram. • • • .
Up/Down
Counter Integrated Circuit Data. • • . . • .
Front Panel Interconnect Integrated Circuit Data
Encoder Assembly Timing Diagram. .
Corrective Maintenance Flowchart.
Corrective Maintenance Flowchart .
Corrective Maintenance Flowchart.
IF Gain and Bandwidth Performance, Test Setup
SIN Ratio Performance, Test Setup. • • .
Detection Mode Performance, Test Setup .
MAN/AGC Performance, Test Setup • • .
Frequency Tuning Performance, Test Setup
Power Supply Troubleshooting Tree. . • .
Input Converter Troubleshooting Tree. • • •
10.7 MHz
Filter Switch Troubleshooting Tree
455 kHz Filter Switch Troubleshooting Tree • •
USB Filter Switch Troubleshooting Tree. . • •
ISB/LSB
Filter Switch Troubleshooting Tree .
455 kHz
Amplifier/AM Detector Troubleshooting Tree • • • .
FM/CW/SSB
Detector Troubleshooting Tree .
FM Detector TrOUbleshooting Tree. . .
Audio Amplifier Troubleshooting Tree
Audio Amplifier Troubleshooting Tree . . . • . .
1-1
2-1
2-2
2-3
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
3-13
3-14
3-15
3-16
3-17
3-18
3-19
3-20
3-21
3-22
3-23
3-24
3-25
4-1a
4-1b
4-1c
4-2
4-3
4-4
4-5
4-6
4-7
4-8
4-9
4-10
4-11
4-12
4-13
4-14
4-15
4-16a
4-16b
x
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W J-8718 HF RECEIVER
LIST
OF ILLUSTRATIONS (Conttd)
CONTENTS
Figure
4-17a
4-17b
4-18
4-19
4-20
4-20a
4-21
4-22
4-23
4-24
4-25
4-26
5-1
5-2
5-3
5-4
5-5
5-6
5-6A
5-6B
5-7
5-8
5-9
5-10
5-11
5-12
5-12A
5-13
5-14
5-15
5-15A
5-16
5-16A
5-17
5-18
5-19
5-20
5-21
ISB Detector/Audio Troubleshooting Tree .
ISB Detector /Audio Troubleshooting Tree .
Phase Detector Timing Diagram • . . •
Input
Converter Alignment, Test Setup .
10.7 MHz
Filter Switch Adjustment, Test Setup
10.7 MHz Filter Switch Adjustment, Test Setup
455 kHz Amplifier/AM Detector Response Alignment, Test Setup.
455 kHz Amplifier / AM Detector Response Alignment, Typical
Response . . . . . . . . . . . • . . . . . . . . . . . •
455
kHz Amplifier / AM Detector Gain Adjustment, Test Setup
ISB Detector/Audio Adjustment, Test Setup . . . . . . . . .
FM Discriminator Alignment, Test Setup . . . . . . • . . •
FM Discriminator Alignment, Typical Response . • • . . .
WJ-8718 HF
Receiver, Front Panel, Location of Components.
WJ-8718 HF Receiver, Rear View, Location of Components .•••.
WJ-8718 HF Receiver, Top View, Location of Components •.
WJ-8718 HF Receiver, Bottom View, Location of Components • .
Type 76240
Power Distribution (A1), Location of Components
Type 791616 RF Filter (A2), Location of Components. . • .
Type 791616
Input Filter (Product Improvement) A2, Location
of Components • . • . . . . . . . • . . • . . . • . . . • .
Part 280093 30 MHz Low Pass Filter (Product Improvement) A2A1,
Location of Components . . . • . . . . . .
Type 791592-1
Input Converter (A3) . • . . . . . . . . •
Part 34748 1st Mixer, 1st IF (A3A1) ••..•....•.
Part 34749 2nd Mixer/2nd IF Amplifier (A3A2) ..•..
Part 280080 Filter Board (A3A3), Location of Components.
Type 791569 IF Motherboard (A4), Location of Components
Type 791594 10.7 MHz Filter Switch (A4A1), Location of Components
Type 791594 10.7 MHz Filter Switch, (Product Improvement) A4A1,
Loca tion of Components . . . . . . . . . . . . . . . . . . .
Type 71430 10.7
MHz/455 kHz Converter (A4A2), Location of
Components. . . . . . . . . . . . . . . . . . . . . . . . .
Type 791595 455
kHz Filter Switch (A4A3), Location of Components
Type 791596 USB Filter Switch (A4A4), Location of Components
Type 791596 USB Filter Switch (Product Improvement) A4A4,
Location of Components • . • . . . . . • . . . . . . .
Type 791597 ISB, LSB
Filter Switch (A4A5) . • . • . . . . •
Type 791597 ISB/LSB
Filter Switch (Product Improvement)
Location of Components . . . . . . . . . • . . . . • . . • . .
Type 78112 AGC
Amplifier (A4A6), Location of Components. •
Type 72488 455
kHz Amplifier/AM Detector (A4A7), Location of
Components. . . . . • . • . • • • . . • • • • • . . . . .
Type 791598 ISB
Detector/Audio (A4A8), Location of Components
Type 791599 FM, CW, and SSB Detector (A4A9), Location of
Components. . • . • . . . . • • • . . . . . . . . • . . • .
Type 7459 Audio
Amplifier (A4A10), Location of Components ..
Page
·4-32
·4-32
4-59
4-75
·4-76
.4-76a
4-78
4-78
·4-79
4-81
·4-83
•4-83
5-7
5-7
5-9
5-11
5-14
.5-15A
.5-15B
• .5-15C
5-16
·5-17
5-18
5-21
5-23
5-26
.5-27C
5-28
5-30
5-32
.5-33B
5-34
5-36
•
.5-36B
5-40
5-42
5-46
5-50
xi
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CONTENTS
Figure
WJ-8718 HF RECEIVER
LIST OF ILLUSTRATIONS (Cont'd)
5-22
5-23
5-24
5-25
5-26
5-27
5-28
5-29
5-30
5-31
5-32
5-33
5-34
5-35
5-36
5-37
5-38
5-39
6-1
6-1a
6-2
6-3
6-3a
6-4
6-5
6-6
6-6a
6-7
6-7a
6-8
6-9
6-10
6-11
xii
Type 791570 Synthesizer Motherboard (A5), Location of Components . .
Type 791630 1st and 3rd LO Synthesizer/Timebase (A5A1),
Location of Components . . . . . . . . . . • . . . . . . . . . .
Type 791629 1st LO VCO Assembly (A5A1A1), Location of Components.
Part 34750 1st LO Voltage Controlled Oscillator (A5A1A1A1),
Location of Components ..................
Type 791600 1st and 3rd LO Synthesizer (A5A1A2), Location of
Components. ...•...................
Type 791601 2nd LO Synthesizer (A5A2), Location of Components
Type 791576 BFO Synthesizer (A5A3), Location of Components. . .
Type 791580 I/O Motherboard (A6), Location of Components. . .
Type 791575-2 Manual Tuning Up/Down Counter (A6A1), Location of
Components. . • . . . . . . . . . • . . . . . . . . . . . . .
Type 791828 Front Panel Interconnect (A6A2), Location of
Components. . . . . . . . . . . . • . . . . . . . . . . . . .
Type 791874-1 Manual Tuning Module (A7), Location of Components
Type 791874-1 Manual Tuning Module (A7), Rear View, Location of
Components. ........................
Type 791589 Tuning Resolution (A7A1), Location of Components • .
Type 791578 Frequency Display (A8), Location of Components . . . .
Type 791827 BFO Switch (A9), Location of Components. .....
Type 791684-2 Front Panel Control (A10), Location of Components.
Type 791583 Upper Panel Control (A10A1), Location of Components
Type 791826 Lower Panel Control (A10A2), Location of Components
Type 791616 RF Filter (A2), Schematic Diagram 34437 .....
Type 791616 Input Filter (A2), SChematic Diagram 380082. . . •
Type 791592 Input Converter (A3), Schematic Diagram 51178 • . •
Type 791594 10.7 MHz Filter Switch (A4A1), Schematic Diagram
51177 ...........................
Type 791594 10.7 MHz Filter (A4A1), Schematic Diagram 480103
Type 71430 10.7 MHz/455 kHz Converter (A4A2), SChematic
Diagram 34384 . . . . . . . . . . . . . . . . . . . . •
Type 791595 455 kHz Filter Switch (A4A3), SChematic Diagram
43561 . . . . . . . . . . . . . . . . . . . . . . .
Type 791596 USB Filter Switch Option (A4A4), Schematic
Diagram 43196 . . . . . . . . . . • . . . . . . . .
Type 791596 USB Filter Switch Option (A4A4), Schematic
Diagram 480102 . . . • . . • . . . . . . . . . . . . .
Type 791597 ISB/LSB Filter Switch Option (A4A5), Schematic
Diagram 43249 . . . . . • . • . • . . . . . . . . . . •
Type 791597 ISB/LSB Filter Switch Option (A4A5), Schematic
Diagram 480105 • • • . . . . . . . . . . • . . • • . . . . . . .
Type 78112 AGC (A4A6), SChematic Diagram 43229 . . . . • .
Type 72488 455 kHz Amplifier/AM Detector (A4A 7), Schematic
Diagram 51168 .•.....................
Type 791598 ISB Detector/Audio (A4A8), Schematic Diagram 43231. .•
Type 791599 FM/CW /SSB Detector (A4A9), Schematic Diagram 43198.
5-53
5-56
5-57
5-60
5-62
5-66
· 5-72
· 5-76
5-78
5-80
5-81
• 5-82
5-83
· . 5-84
5-86
5-87
5-88
5-89
6-1
· 6-1a
• 6-3a
6-5
6-5a
6-7
6-9
· 6-11
· .6-11a
· . 6-13
• .6-13a
6-15
· 6-17
· 6-19
6-21
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WJ-8718 HF RECEIVER
Figure
LIST OF ILLUSTRATIONS (Concluded)
CONTENTS
6-12
6-13
6-14
6-15
6-16
6-17
6-18
6-19
6-20
6-21
6-22
6-23
Table
Type 7459 Audio Amplifier (A4A10), Schematic Diagram 43230. .
Type 791630 1st and 3rd LO Synthesizer/Time Base Assembly
(A5A1), Schematic Diagram . . . . . . . . . . . . . . . . .
Type 791629 Voltage Controlled Oscillator (A5A1Al), Schematic
Diagram 51198 . . . . . . . . . . . . . . . . . . . . .
Type 791600 1st and 3rd LO Synthesizer/Time Base (A5A1A2),
Schematic Diagram 61247 (Sheet 1 of 2) ........•..
Type 791600 1st and 3rd LO Synthesizer/Time Base (A5A1A2),
Schematic Diagram 61247 (Sheet 2 of 2). . . . . . . . . . .
Type 791601 2nd LO Synthesizer (A5A2), Schematic Diagram 61256
Type 791576 BFO Synthesizer (A5A3), Schematic Diagram 51183. .
Type 791576-2 Manual Tuning Up/Down Counter (A6A1), Schematic
Diagram 51180 . . . . . . • . . . . . • . . . . • . . . . .
Type 791578 Frequency Display (A8), Schematic Diagram 43242 • .
Type WJ-8718 HF Receiver Main Chassis, Schematic Diagram 580032
(Sheet 1 of 6 and Sheet 5 of 6). . . . . . . . . • . . • . . . . .
Type WJ-8718 HF Receiver Main Chassis, Schematic Diagram 580032
(Sheet 2 of 6 and Sheet 3 of 6). . . . . . . . . . . . . . . . . . .
Type WJ-8718 HF Receiver Main Chassis, Schematic Diagram 580032
(Sheet 4 of 6 and Sheet 6 of 6). .................
LIST
OF TABLES
6-23
. 6-25
6-27
6-29
6-31
6-33
6-35
6-37
6-39
6-41
6-43
6-45
1-1
2-1
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
4-1
4-2
4-3
4-4
4-5
Type WJ-8718 HF Receiver, Specifications .
Remote Input Lines Identification .....
Receiver IF Bandwidth Relationships . . . .
Detection Mode Output Signal Relationships. .
1st and 2nd LO Tuning Increments ......
1st and 2nd LO Frequencies Versus Tuned Frequency •
Receiver's Phase Lock Loop Characteristics .
Code Converter U4, Truth Table. . . .
Count Sequence, 1st LO Swallow Counter . •
1st LO Divider Count-Down Cycles. . . . •
Band
Select Coding. • . . • . . . . . . .
Data Selector 14512, Digit Control Codes. •
BFO
Switch Truth Tables . . . • .
Periodic Maintenance Schedule . . • . . .
Test Equipment Required. . . . . . . .
Receiver Minimum Performance Standards
Input Converter Voltage Table. . . . .
10.7 MHz Filter Switch Voltage Table ...
1-5
2-5
3-2
3-3
· 3-16
· 3-17
3-21
3-35
• 3-37
3-38
3-40
· 3-46
3-51
4-1
. .
.. 4-4
4-6
. . 4-36
· 4-38
xiii
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CONTENTS
LIST OF TABLES (Concluded)
Table
W J-8718 HF RECEIVER
4-5a
4-6
4-7
4-8
4-8a
4-9
4-9a
4-10
4-11
4-12
4-13
4-14
4-15
4-16
4-17
4-18
4-19
4-20
4-21
4-22
4-23
4-24
xiv
10.7 MHz Filter Switch Voltage Table. . . .
10.7 MHz/455 kHz Converter Voltage Table
455 kHz Filter Switch Voltage Table . . . . . • • •
USB
Filter Switch Voltage Table. .....
USB
Filter Switch Voltage Table (Revision G)
ISB/LSB
Filter Switch Voltage Table . . • .
ISB/LSB
Filter Switch Voltage Table . . . . .
455
kHz Amplifier/AM Detector Voltage Table.
FM/CW /SSB Detector Voltage Table .
Audio
Amplifier Voltage Table. . . . .
ISB
Detector/Audio Voltage Table • . .
AGC
Voltage Table. . . . • . . . . . .
Front Panel Interconnect Voltage Table.
VCO Band Select Code .
1st La Frequency Chart
2nd La Frequency Chart
BFa Frequency Chart
Output Divider U10 Frequency Chart.
Time Base Frequency Chart. . . • . .
VCO
Alignment Parameters. . . . .
Loop
Test Point Voltages • . . . . .
2nd
La Synthesizer Tuning Parameters
.4-38a
4-39
. . 4-41
· 4-43
. .4-43a
· 4-44
.4-44a
· 4-46
4-48
· 4-50
· 4-52
· 4-53
4-56
· 4-58
· 4-59
4-63
4-66
4-67
4-68
· 4-70
4-72
4-73
-- -- -- -- -- -- -- -- ~ - -- -- ------ ----
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WJ -8718 HF RECEIVER
THIS PAGE LEFT BLANK
CONTENTS
xv
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Page 1 of 2
ERRATA
January 29, 1980
The following corrections to the WJ -8718 Instruction Manual (Revision V, 01/80)
should be noted and incorporated in the text.
1) Page 2-4, Paragraph 2.3.11, 3rd line; change "Figure 6-18" to "Figure
6-19" .
2) Page 3 -3a, Paragraph 3.2. 2a, 2nd line; change "Figure 6-3a" to "Figure
6-1a".
3) Page 3 -40, Paragraph 3.3. 7.3, 2nd line; change "Figure 6-14" to "Figure
6-15" .
4) Page 3-47, Paragraph 3.4.2, 5th line; change "Figure 6-20" to "Figure
6-23".
5) Page 3-51, Paragraph 3.4.9, 4th line; change "Figure 6-20" to "Figure
6-21".
6) Page 3-51, Paragraph 3.4.10, 2nd line; change "Figure 6-20" to "Figure
6-21" .
7) Page 4-56, Paragraph 4.7.16.2, item 1; change "Figure 6-13" to "Figure
6-23".
8) Section V, Replacement Parts List, page 5-52, Paragraph 5.5.5, TYPE
791570 SYNTHESIZER MOTHERBOARD; add listing for VI and V2, Integrated
Circuits, Part no. 7805 DC, Mfr. Code 07263.
9) Section V, Replacement Parts List, page 5-53, Figure 5-52, Type 791570
Synthesizer Motherboard (A5);
a) Add capacitor C61 between L3 and LI.
b) The labeling on the side view detail should be changed as shown on
the following page.
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Page 2 of 2
Cl THRU C29
C30THRU C58
January 29, 1980
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