Codan X-2 Service Manual page 5

X-2 Technical Service Manual
5.3.4
5.3.5
5.3.6
5.4 Dismantling and Assembling............................................................................5-8
5.4.1.
5.4.2
5.4.3
5.4.4
5.4.5
5.4.6
6 Channel Additions
7 Adjustments
7.1 Introduction ....................................................................................................7-1
7.2 Test Equipment Required................................................................................7-1
7.3 Voltage Regulators .........................................................................................7-1
7.4 Crystal Oven ...................................................................................................7-2
7.5 Test Mode ......................................................................................................7-2
7.6 VCO Checks and Adjustments ........................................................................7-4
7.6.1
7.6.2
7.6.3
7.7 45 MHz Filter Alignment.................................................................................7-5
7.7.1
7.7.2
7.8 455 kHz IF and N/L Alignment .......................................................................7-7
7.9 Frequency Adjustment.....................................................................................7-8
7.9.1
7.9.2
7.10 Mute Adjustment.............................................................................................7-9
7.11 PA Adjustments.............................................................................................7-10
7.11.1 Driver Bias ...............................................................................7-10
7.11.2 PA Bias ....................................................................................7-10
7.11.3 Output Power ...........................................................................7-11
7.11.4 Intermodulation ........................................................................7-12
7.12 Receiver Performance Checks........................................................................7-13
7.12.1 Sensitivity and S+N/N ratio ......................................................7-13
7.12.2 AGC Check ..............................................................................7-13
7.12.3 Audio Output ...........................................................................7-13
Publication No: 15-02047
Transmitter Failure .....................................................................5-7
Unlocked Synthesiser..................................................................5-7
PA Failure ..................................................................................5-8
General.......................................................................................5-8
Top and Bottom Covers .............................................................5-9
Rx/Exciter & Control PCB .........................................................5-9
Front Panel PCB.........................................................................5-9
PA and Filter Assembly.............................................................5-10
Replacement of PA Transistors .................................................5-11
.........................................................................................6-1
.......................................................................................................7-1
VCO1 Check ..............................................................................7-4
VCO2 Check ..............................................................................7-4
VCO2 Adjust..............................................................................7-5
Alignment - Method 1.................................................................7-6
Alignment - Method 2.................................................................7-7
Frequency Adjust USB ...............................................................7-8
Frequency Adjust LSB................................................................7-9
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