Giga-tronics GT 9000, Руководство по эксплуатации и техническому обслуживанию

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4.1.5 YIG Driver Calibration
This procedure calibrates each driver at the high and low ends of its frequency range to ensure
the accuracy of the coarse and fine tuning of the YIG oscillators. PC boards A16 and A19 are
referenced in this procedure.
1. Reference YIG: Monitor TP1 on the A16 PC board. On the A19 board, adjust the min
and max pots of the reference YIG driver at the min and max reference frequencies for
0 V +1 V on TP1. Refer to Table 4-2.
Output Frequency, GHz Adjust Pot A19 Reference Frequency, GHz
7.9 R2 Max 7.805
2.01 R1 Min 1.905
2. Since the min and max pots interact, repeat step 1 until both voltages are 0 V +1 V.
3. Optional Frequency Check: Monitor the reference frequency test port (J5 on the RF
module).
4. Output YIGs: Monitor TP1 on the A18 board. On the A19 board, adjust the min and max
pots of the output YIG drivers, at the min and max frequencies of the YIGs, for test
point voltages of 0 V +1V on TP1. Refer to Table 4-3.
Set Frequency, GHz Adjust Pot, A19
7.9 R12 Max
2.1 R11 Min
20.0 R24 Max
8.0 R23 Min
26.0 R26 Min
20.0 R35 Max
5. Since the min and max pots for each YIG interact, repeat step 4 for each band until the
output voltages are all 0 V +1 V.
6. Optional Frequency Check: Monitor the front panel RF output with a frequency counter.
7. After all of the min and max pots have been calibrated, monitor the test points on the
A16 and A18 PC boards (as described above), and use the front panel up/down keys to
step through the frequency range in 100 MHz increments. Both test points should
remain at 0 V +1 V.
Table 4-2. YIG Reference Frequency
Table 4-3. YIG Output Frequency
Model GT 9000 Microwave Synthesizer
4-4
Manual No. 120AM00250, Rev C, September 1998