Garmin GTX 3000 매뉴얼

{카테고리_이름} Garmin GTX 3000에 대한 매뉴얼을 온라인으로 검색하거나 PDF를 다운로드하세요. Garmin GTX 3000 3 페이지. Transmitter tuning

Manual Transmitter Tuning

1. Power down the unit and connect the antenna port to a Mode S / ATCRBS interrogation

generator (SDX2000 or equivalent) through a cable with 1.5 ± 0.1 dB loss.

2. Set the interrogation generator for ATCRBS interrogation at 100 PRF and power level of -50

dBm.

3. Connect the UUT output from the interrogation generator to the oscilloscope input. The

oscilloscope port should be set for 50 ohm impedance, or should have an external 50 ohm

load connected if using a high impedance setting.

4. Refer to Error! Reference source not found. for locations of the alignment components

referenced in the steps that follow.

Figure Error! No text of specified style in document..1. Alignment Point Locations

5. Adjust the screws on trimmer caps C1027, C1024, C2020, C2035, C2025, and C2017

clockwise until resistance is felt, then 4 turns counterclockwise.

6. Adjust potentiometers R2012 and R2003 fully counterclockwise, then turn clockwise one

quarter turn.

7. If not connected, reconnect the ribbon cable between the transmitter and main boards.

8. Turn on the unit power.

9. Using the GTX3000 SI Tool, put the unit in test mode.

10. Reply pulses should be seen on the oscilloscope. If not, adjust the scope vertical scale and /

or trigger level until a stable pulse display is obtained. The actual vertical scale settings are

dependent on the characteristics of the interrogation generator UUT output.

11. Adjust the horizontal scale on the oscilloscope to 200 nS per division to display a single

pulse.

12. While observing the pulse on the oscilloscope, adjust trimmer cap C2017 for maximum pulse

amplitude.

GTX 3000 TX Tune Procedure