sunair RT-9000C, Руководство по эксплуатации и обслуживанию

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RT-9000C Hardware Supplement
Document No. 8128000602
Revision A (19 Mar 2007)
8-30
RT-9000 C
8.3.2.3.2 ALC, Low Power ALC, and ACC Adjustments
This procedure describes how to set the both ALC (Automatic Level Control) controls. It also describes how
to adjust of the Automatic Carrier Control (ACC), an AM-only control. All adjustments are all transmit-state
adjustments. These adjustments should be performed after the Digital IF 1A2A4 Assembly is replaced.
All adjustments are performed on the Digital IF 1A2A4 Assembly. Refer to Figure 8.11 to locate the applicable
adjustment points.
Preliminary
1. If the RT-9000C was powered-up, power it down now.
2. Observe proper Electrostatic Discharge damage prevention practices during this entire
procedure.
3. Remove the RT-9000C top cover. Refer to Section 5.2.1 in the RT-9000 Operation and
Maintenance manual.
4. Remove card cage top cover. Refer to Figure 5.4.1.3. This cover extends the full width of the RT-
9000C and is closest to the front panel.
Note: The RT-9000C uses loose hardware. When removing the card cage
cover fasteners, account for any lost hardware items to prevent
accidental short circuits later.
5. Power up the RT-9000C.
6. Locate the Digital IF Transmit adjustment points. Refer to Figure 8.11.
Adjustments
7. Connect 150 Watt 50-Ohm dummy load to RT-9000C ANT connector J4. Connect an RF
voltmeter to monitor the voltage across the dummy load.
8. Connect a CW key to the RT-9000C front-panel CW jack.
9. Set the RT-9000C as follows; Frequency: 8.000 MHz, Mode: CW, Power Setting: 125 Watts
10. Key the RT-9000C using the CW key. Adjust ALC potentiometer 1A2A4 R77 until the RF
voltmeter indicates 79 Vrms. Unkey the RT-9000C.
11. Reset the Power Setting to 65 Watts.
12. Key the RT-9000C using the CW key. Adjust LOW POWER ALC potentiometer 1A2A4 R78
until the RF voltmeter indicates 57 Vrms. Unkey the RT-9000C.
13. Reset the RT-9000C as follows; Mode: AM, Power Setting: 125 Watts.
14. Key the RT-9000C using the CW key. Adjust ACC potentiometer 1A2A4 R70 until the RF
voltmeter indicates 47 Vrms. Unkey the RT-9000C.
15. Disconnect all test equipment. This completes the ALC and ACC adjustments.
16. Re-install card cage top cover and RT-9000C top cover.