Adjustments
7-18 HF SSB Transceiver 9323/9360/9390/9780 Technical Service Manual
This opens the noise limiter gate and prevents the AGC from operating
during the alignment.
q Set the signal generator output to 0.7 mV PD at a frequency of 8.4 MHz
±0.4 MHz.
q Connect the signal generator to the receiver input.
q Connect an oscilloscope with a 10X probe to TP201.
q Connect the external trigger input to TRIG Test Point on the PCB.
q Set the oscilloscope as follows:
Channel One
20 mV/division using the 10X probe
Timebase
2 ms/division
Trigger
External trigger
q Select Test mode by fitting the shorting link to Link 1 as shown in
Figure 7-1.
q Switch on the transceiver, then select Test 4.
q Adjust the oscilloscope’s trigger control for a constant sweep (positive
trigger).
q Slowly adjust the potentiometer on the jig for a display on the oscilloscope
similar to that show in Figure 7-2.
q Adjust transformers T3, T4 and inductor L30 for minimum ripple response.
q Switch off the transceiver.
q Remove the jig from the PCB.
q Remove the shorting link from B-E and return it to its parking position
(ground pins E-E).
q Solder sweep link S.
q If you do not want to perform any other testing, remove the Test mode link
on the Microprocessor PCB and return it to its parking position (see
Figure 7-1).
Alignment—method 2
This alignment method is the same as given for 45 MHz filter alignment for
assembly 08-04962 (see page 7-15, Alignment—method 2).
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