Codan Radio Communications VT-3H040-S-HSO User Manual

VT-3H040 VHF Amplifier Instruction Manual     IM20-VT3040AMP 

iii 

 

Page 

1 GENERAL....................................................................................................................1-1 

1.1 Introduction.......................................................................................................1-1 
1.2 Performance 

Specification................................................................................1-1 

2 

THEORY OF OPERATION.........................................................................................2-1 
2.1 Amplifier 

Operation..........................................................................................2-1 

2.2 Power 

Requirements .........................................................................................2-1 

2.3 RF 

Circuitry ......................................................................................................2-1 

2.3.1  VT-3H040 Lowpass Filter ................................................................................2-2 
2.4 

Power Control Circuitry....................................................................................2-2 

2.5 

Power Sensing Circuitry ...................................................................................2-3 

2.5.1  Output Power Sense..........................................................................................2-3 
2.5.2 VSWR 

Sense.....................................................................................................2-4 

2.5.3 VSWR 

Overload ...............................................................................................2-4 

3 

VT-3H040 AMPLIFIER ALIGNMENT ......................................................................3-1 
3.1 General..............................................................................................................3-1 
3.2 Repair 

Note .......................................................................................................3-1 

3.3 

Recommended Test Equipment List.................................................................3-1 

3.4 

Printed Circuit Board Numbering Convention .................................................3-2 

3.5 

Standard Factory Settings and Jumper Configuration ......................................3-2 

3.6 

VT-3H040 Amplifier Alignment ......................................................................3-2 

3.6.1 General..............................................................................................................3-2 
3.6.2  VT-3H040 Amplifier Adjustment.....................................................................3-3 

4 

ILLUSTRATIONS AND SCHEMATIC DIAGRAMS ...............................................4-1 
4.1 

VT-3H040 Output Lowpass Filter Component Layout ....................................4-1 

4.2 

VT-3H040 Output Lowpass Filter Schematic Diagram ...................................4-1 

4.3 

VT-3H040 Amplifier Component Layout ........................................................4-2 

4.4 

VT-3H040 Amplifier Schematic Diagram........................................................4-3 

5 PARTS 

LISTS ..............................................................................................................5-1 

5.1 

VT-3H040 Amplifier Electrical Parts List........................................................5-1 

5.2 

VT-3H040 Lowpass Filter Electrical Parts List ...............................................5-4 

5.3 

VT-3H040 Amplifier Mechanical Parts List ....................................................5-4 

6 REVISION 

HISTORY..................................................................................................6-1