Icom IC-751A Manuals

Manuals and User Guides for Icom IC-751A. We have 3 Icom IC-751A manuals available for free PDF download: Service Manual, Instruction Manual

Icom IC-751A Service Manual (151 pages)

Brand: Icom | Category: Transceiver | Size: 31.6 MB

Table of Contents
3
General Specifications
5
Transmitter Specifications
5
Receiver Specifications
6
Outside and Inside Views
7
Front Panel
7
Display
9
Top Panel
9
Rear Panel
10
Main Unit View
11
Logic and PLL Units View
13
RF Unit View
15
PA Unit View
15
Block Diagram
17
Circuit Description
18
Receiver Circuits
18
RF Circuits (RF and Connector Units)
18
IF Circuits/Rf Unit
18
Main Unit
19
Filter Section (Main Unit)
19
Noise Blanker Circuit
19
Two Signal Receive Characteristics Diagram
19
Notch/Detector/Agc Circuit
20
FM if Amplifier and Detector Circuits
20
AF Amplifier Circuits
20
AGC Circuit Schematic Diagram
20
Transmitter Circuits
21
MIC Amplifier Circuit/Balanced Modulator Circuit/Ssb and am Transmitter if Circuits/Compressor Circuit
21
S-Meter Circuit
21
Squelch Circuit
21
CW, RTTY Oscillation Circuits
22
CW Keying Circuit
22
FM Oscillator and Modulator Circuits/Bfo Circuits
22
Transmitter if Amplifier Circuits
22
RF Unit Block Diagram
23
PBT Oscillator Circuit
23
SW Sidetone Circuit
23
PA Unit/Filter, Connector Units
23
Monitor Circuit/Monitor Preamplifier Circuit
24
ALC/APC Circuit
24
Transmitter Meter Circuits
24
Vox and Anti-Vox Circuits
24
Power Supply Circuits/Pll Circuits
25
Meter/Filter Switching Circuit
25
8V Regulator Circuit/Receive/Transmit 8V (R8V) Regulator Circuit
25
Power Supply Switching Circuit/Regulator Switching Timing Circuit
25
Reference Frequency Oscillator and Marker Circuits
26
PLL Sub-Loop Block Diagram
26
Main Loop Circuits
27
Pll IC
27
Marker Generator Chart
27
Vco
28
Loop System
28
Loop Filter and Mute Circuits
28
In-Loop Local Oscillator Circuit/Sub-Loop
28
Logic Unit
29
CPU/CPU Input Control Circuit
29
PLL Data
29
How to Derive N-Data
29
Custom IC PIN Connection Chart
30
CPU PIN Connection Chart
30
CPU Memory Map
30
I/O Expander Circuit
31
N-Data of PLL
31
N-Data Output Timing Diagram
31
Matrix Unit
32
Y0→DB0-DB3 (Ten Key)
32
Y0→DB4 (Scan Start/Stop)
32
Y1→Db4 (Vfo A/B)
32
Y1→DB5 (Memory Read)/Y1→Db6 (Ham/General)
33
Y1→DB7 (RIT On/Off)/Y2→Db0 (Function)
33
Y2→DB3 (RIT/∆TX Clear)
33
Y2→Db4 (Vfo A=B)
33
Matrix Unit (Cont.)
34
Frequency Differences in Various Modes Chart
34
Display Unit
35
Matrix Unit (End)
35
Display Section
36
Display Data Timing Chart
36
DC/DC Converter Section
36
Other Circuits/Enc 1 and ENC 2 Units
36
Relay Unit
37
Keyer Unit
37
Dot, Dash Inputs and Electronic Keyer Output
37
Spd/Weight/Fan Motor Control
37
Disassembly and Assembly Diagrams
38
Frame Disassembly
38
Front Panel Disassembly
40
Front Panel (2) Disassembly
42
Front Panel (3) Disassembly
44
Rear Panel Disassembly
46
Front Unit Connector Assembly
48
Main Unit Connector Assembly Diagram
50
Logic and PLL Unit Connector Assembly Diagram
51
RF Unit Connector Assembly Diagram
52
Filter Unit Connector Assembly Diagram
52
Rear Panel Connector Assembly Diagram
53
Maintenance and Adjustment
54
Preparation before Servicing
54
PLL Adjustment
55
PLL Unit View
56
Frequency Adjustment
57
Main Unit Illustration
58
Receiver Adjustment
59
Main Unit Illustraton (2)
60
Receiver Adjustment (Cont.)
61
Main Unit Illustration (3)
62
Transmitter Adjustment
63
PA Unit
64
Transmitter Adjustment (Cont.)
65
Main Unit Illustration (4)
66
Transmitter Adjustment (Cont)
67
Main Unit Illustration (5)
68
Transmitter Adjustment (Continued)
69
Main Unit Illustration (6)
70
Board Layouts
71
Front AF Unit Board Layout
71
Front Marker Unit Board Layout
71
Front Mode Switch Unit Board Layout
71
Matrix Unit Board Layout
72
Matrix Switch Unit Board Layout
72
Display Unit/Keyer Unit Board Layouts
73
Logic Unit Board Layout
74
Main Unit Board Layout
75
PLL Unit Board Layout
76
RF Unit Board Layout
77
PA Unit Board Layout
78
PA Connector Unit/Pa Choke Unit Board Layout
79
Filter Unit Board Layout
80
Voltage/Circuit Diagrams
81
Main Unit Circuit Diagram
81
PLL Unit Circuit Diagram
83
Logic Unit Circuit Diagram
85
FR Unit Circuit Diagram
87
Matrix Unit Circuit Diagram
89
Display Unit Circuit Diagram
91
PA Unit Circuit Diagram
93
Filter Unit Circuit Diagram
95
Keye Unit/Front Encoder Units Circuit Diagrams
96
Front Unit Wiring Diagram
97
IC Specifications
99
Linear Ics Specifications
99
Logic Ics Specifications
100
Parts List
105
EF Unit/Front Unit Parts List
105
Display Unit Parts List
106
Logic Unit Parts List
108
Matrix Unit Parts List
111
PLL Unit Parts List
113
Main Unit Parts List
116
RF Unit Parts List
127
Filter Unit Parts List
131
PA Unit Parts List
133
Keyer Unit Parts List
135
Mute Unit Parts List
135
Options Installation
136
Optional Filters
136
Filter Reverse Switches
136
FL-52A, Fl-53A, FL-63A, FL-70 Filters Installation
136
Optional IC-PS35 Internal Power Supply
137
FL-33 Installation
137
Optional IC-EX310 Voice Synthesizer Unit
138
Optional CR-64 High-Stability Crystal Unit
138
Optional UT-30 Programmable Encoder Unit
139
Filter Characteristics Chart
139
Filter Combinations Chart
140
Filter System
140
Filters Diagram
140
IC-751A Schematic Diagram
141

Icom IC-751A Instruction Manual (64 pages)

hf all band transceiver general coverage receiver

Brand: Icom | Category: Receiver | Size: 4.51 MB

Table of Contents
3
Features
5
Section 2 Specifications
6
Section 3 3- Control Functions
8
- Front Panel
  8
- Frequency Display
  16
- Top Panel
  16
  - Rear Panel
    17
    
    Installation
    19
    
    Planning
    19
- Mounting the Transceiver
  19
- Antenna
  19
- Microphone
  20
- 5- Cw Key
  20
  - Power Supply
    20
  - Ground
    21
Section 5 System Interconnections
22
- Ac Power Supply
  22
- External (Linear) Amplifier
  22
- Antenna Tuner
  23
- Rtty Terminal Unit
  24
- Sstv Unit
  25
  - Accessory Socket Connections
    25
Section 6 General Operation
26
- Settings
  26
- Basic Operation
  26
- Ssb Operation
  29
- Cw Operation
  31
- Am Operation
  31
- Fm Operation
  32
- Rtty Operation
  33
  - General Coverage Receiver
    34
Section 7 Functions Operation
36
- Vox Operation
  36
- Speech Compressor Operation
  36
- Noise Blanker (Nb) Operation
  37
- Cw Semi/Full Break-In Operation
  37
- Split (Duplex) Operation
  38
- Fm Repeater Operation
  38
- Passband Tuning (Pbt) Operation
  39
- Notch Filter Operation
  40
- Filter Switch Operation
  40
- Rit/^Itx Operation
  40
- Monitor Operation
  42
- Microphone Up/Down Operation
  43
- Agc Operation
  43
- Preamp/Att Switch Operation
  43
Section 8 Memory and Scanning Operation
44
- Memory Channel Selection
  44
- Programming Memory Channels
  44
  - Memory Clearing
    45
  - Memory Scan
    45
  - Mode Scan
    46
  - Programmed Scan
    46
    
    Scan Resumption
    46
Section 9 Other Functions
47
- Vswr Readings
  47
- Wwv/Wwvh Reception
  47
Section 10 10- Options Installation
48
- 10-1 Filters
  48
- IC-Ps35
  50
- IC-Ex310 Voice Synthesizer Unit
  51
  - High-Stability Crystal Unit
    51
- Programmable Encoder Unit
  52
- Circuit Description
  53
  - Receive Circuits
    53
- Transmit Circuits
  54
- 11-3 Pll Circuits
  55
  - Logic Circuits
    56
  - Cleaning
    57
- Maintenance
  57
  - Adjustments
    57
  - TOP Vievy
    58
- Bottom View
  58
Section 13 Inside Views
59
- Rf Unit
  60
- Adjustment Locations
  61
Section 14 Block Diagram
62
Section 15 Options
63

Icom IC-751A Instruction Manual (64 pages)

HF All Band Transceiver General Coverage Receiver

Brand: Icom | Category: Transceiver | Size: 6.08 MB

Icom Categories

Transceiver Receiver Repeater Radio Two-Way Radio

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Icom IC-751A Manuals

Icom IC-751A Service Manual (151 pages)

Table of Contents

Icom IC-751A Instruction Manual (64 pages)

Table of Contents

Icom IC-751A Instruction Manual (64 pages)

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