Adjustments
7-10 HF SSB Transceiver 9323/9360/9390/9780 Technical Service Manual
VCO checks and adjustments
VCO1 check
108-04962
There is no adjustment for VCO1, which is located on the Rx/Exciter PCB. To
check VCO1 is operating correctly perform the following in Test mode.
q Select Test 1.
q Ensure the screening can is over VCO1 and Mixer 1 for the test.
q Connect a DC voltmeter to TP1 and check for a reading between 9.0-11.5 V.
The frequency at TP4 should measure 60 MHz ±100 Hz.
q Select Test 2.
q Check the voltage at TP1 reads 19-25 V. The frequency at TP4 should
measure 75 MHz ±100 Hz.
q Select Test 3.
q Check the voltage at TP1 reads 2-4 V. The frequency at TP4 should measure
45.25 MHz ±100 Hz.
VCO2 check
108-04962 and 08-05322
VCO2 is located on the Rx/Exciter PCB and can be checked in Test mode. The
test point and measurement results for 108-05322 are given in brackets.
q Select Test 1.
q Connect a DC voltmeter to TP5 (TP9) and check for a reading between
7.8-8.2 V. The frequency at TP8 should measure 44.5445 MHz ±100 Hz
(44.5455 MHz ±100 Hz).
q Select Test 2.
q Check the voltage at TP5 (TP9) reads between 11-17 V. The frequency at
TP8 should measure 44.5485 MHz ±100 Hz (44.5495 MHz ±100 Hz).
q Select Test 3.
q Check the voltage at TP5 (TP9) reads between 2-5 V. The frequency at TP8
should measure 44.5405 MHz ±100 Hz (44.54145 MHz ±100 Hz).
q If the measurements are not within the stated limits, adjust VCO2 (see page
7-11, VCO2 adjust).
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