5. Log Amplifier Adjustments

23.Decrease the frequency synthesizer’s output level 10 dB. Press

CREFERENCE LEVEL) 0 dBm, and adjust the frequency synthesizer’s output level for a DVM indication of + 1.00 k.001 Vdc.

24.Verify that attenuator is set at 10 dB. Decrease the frequency synthesizer output level by 10 dB. Press [REFERENCE LEVEL] -60 dB.

25.Adjust A4A3R83 LGlO for DVM indication of + 1.000 kO.010 V dc. See Figure 3-34 location of adjustment. If unable to adjust LGlO for proper indication, increase or decrease value of A4A3R54. Refer to Table 3-3 for range of values.

26.Decrease the frequency synthesizer output level by 10 dB.

27.Key in [REFERENCE LEVEL_) -70 dB.

28.Adjust A4A2R14 LG20 for DVM indication of + 1.000 fO.O1O

V dc. See Figure 3-34 for location of adjustment. If unable to adjust LG20 for proper indication, increase or decrease value of A4A2R18. Refer to lkble 3-3 for range of values.

29. Press [INSTR PRESET] to reenable IF Step Gains.

3.66 Adjustments

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HP 8568B manual Log Amplifier Adjustments