Table Of Contents - ozQRP MST3 Construction And Operation Manual

1 Introduction .............................................................................................................................................................. 5
2 Block Diagram .......................................................................................................................................................... 7
3 Circuit Description ................................................................................................................................................. 8
3.1 Carrier Oscillator ............................................................................................................................................................... 8
3.2 SSB generator ...................................................................................................................................................................... 8
3.3 Crystal Filter ........................................................................................................................................................................ 9
3.4 Transmit mixer ................................................................................................................................................................... 9
3.5 Power amplifier .................................................................................................................................................................. 9
3.6 Power Supply and RX/TX switching ...................................................................................................................... 10
3.7 Receive mixer ................................................................................................................................................................... 10
3.8 Product Detector ............................................................................................................................................................. 10
3.9 Audio Power Amplifier ................................................................................................................................................. 11
3.10 Audio AGC .......................................................................................................................................................................... 11
3.11 Intelligent Tone Module .............................................................................................................................................. 12
3.11.1 Overview .................................................................................................................................................................. 12
3.11.2 Circuit operation .................................................................................................................................................. 12
4 Kit Supplied Parts ................................................................................................................................................ 21
5 Individual Parts List ............................................................................................................................................ 23
6 Off Board Parts ...................................................................................................................................................... 26
7 Main Board Construction .................................................................................................................................. 27
7.1 General ................................................................................................................................................................................ 27
7.2 Construction Steps ......................................................................................................................................................... 28
8 Band Pass Filters .................................................................................................................................................. 38
8.1 Circuit description .......................................................................................................................................................... 38
8.2 Construction...................................................................................................................................................................... 39
9 Low Pass Filter ...................................................................................................................................................... 42
9.1 Circuit description .......................................................................................................................................................... 42
9.2 Construction...................................................................................................................................................................... 42
10 Adding a VFO ......................................................................................................................................................... 45
11 Enclosure ................................................................................................................................................................. 46
11.1 Front Panel ........................................................................................................................................................................ 46
11.2 Rear Panel .......................................................................................................................................................................... 46
11.3 Mounting the PCB ........................................................................................................................................................... 47
12 Wiring up ................................................................................................................................................................. 48
12.1 general ................................................................................................................................................................................. 48
12.2 Headers ............................................................................................................................................................................... 48
MST3 Construction and Operation Manual - Issue 1
C
ONTENTS
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