HP 8568B manual MHz Local Oscillator Adjustment

10. Step Gain and 18.4 MHz Local Oscillator Adjustments

1 dB Gain Step Checks

22.Key in [REFERENCE LEVEL) -19.9 dBm. Set step attenuators to 15 dB. Press MARKER @ twice to establish a new reference.

23.Key in (REFERENCE LEVEL) -17.9 dBm. Set step attenuators to 13 dB.

24.MKR A level, as indicated by CRT annotation, should be .OO f0.5 dB. If not, increase or decrease the value of A4A5R86. Refer to ‘Ihble 3-3 for range of values.

25.Key in (REFERENCE LEVEL) -15.9 dBm. Set step attenuators to 11 dB.

26.MKR A level should be .OO ho.5 dB. If not, increase or decrease the value of A4A5R70. Refer to Table 3-3 for range of values.

27.Key in [REFERENCE LEVEL) -11.9 dBm. Set step attenuators to 7 dB.

28.MKR A level should be .OO ho.5 dB. If not, increase or decrease the value of A4A5R62. Refer to ‘Ihble 3-3 for range of values.

.l dB Gain Step Adjustment

29. Key in LIN, (SHIFT) * (AUTO] (resolution bandwidth), and (REFERENCE LEVEL) -19.9 dBm. Set step attenuators to 13 dB. Press MARKER (nl twice to establish a new reference.

30.Key in [REFERENCE LEVEL) -18.0 dBm. Set step attenuators to 11 dB.

31.Adjust A4A5R51 VR for MKR A level of + 0.10 dB. See Figure 3-49 for location of adjustment.

32.Remove all test equipment from the spectrum analyzer. Connect CAL OUTPUT to RF INPUT.

18.4MHz Local Oscillator Adjustment

33.Press ~NSTR PRESET] and IRECALL) @.

34.Set front-panel FREQ ZERO control to midrange.

35.Adjust A4A5ClO FREQ ZERO to peak signal trace on CRT. See Figure 3-49 for location of adjustment.

3.90 Adjustments