HP 8568B manual DB Gain Step Adjustment, Location of 10 dB Gain Step Adjustments

10.Step Gain and 18.4 MHz Local Oscillator Adjustments

10.If A4A5R33 CAL adjustment does not have sufficient range to adjust trace to the top CRT graticule line, increase or decrease the value of A4A7R60 as necessary to achieve the proper adjustment range of A4A5 CAL adjustment. See Figure 3-39 for the location of A4A7R60. Refer to Table 3-3 for range of values for A4A7R60.

10 dB Gain Step Adjustment

11.Connect CAL OUTPUT to RF INPUT through 10 dB step attenuator and 1 dB step attenuator.

12.Key in LOG (ENTER dB/DIv] 1 dB and [REFERENCE LEVEL) -30 dBm.

13.Set step attenuators to 25 dB.

14.Key in MARKER A. Signal trace should be at the center CRT graticule line, and MKR A level, as indicated by CRT annotation, should be .OO dB.

15.Key in [REFERENCE LEVEL] -40 dBm. Set step attenuators to 35 dB.

16.Adjust A4A5R32 SGlO for MKR A level of .OO dB (CRT MKR A annotation is now in upper right corner of CRT display). See Figure 3-48 for location of adjustment.

A4A5 S T E P LAIN

R32	R44	R54
SGIO	SG20- 1	R70 R62

A4A5

Figure 3-48. Location of 10 dB Gain Step Adjustments

17.If A4A5R32 SGlO adjustment does not have sufficient range to perform adjustment in step 16, increase or decrease the value of A4A7R60 as necessary to achieve the proper adjustment range of A4A5 SGlO. See Figure 3-39 for the location of A4A7R60. Refer to ‘Ihble 3-3 for range of values for A4A7R60. Repeat steps 3 through 16 if the value of A4A7R60 is changed.

18.Key in [REFERENCE LEVEL] -50 dBm. Set step attenuators to 45 dB.

19.Adjust A4A5R44 SG20-1 for MKR A level of .OO dB. See

Figure 3-48 for location of adjustment.

20.Key in CREFERENCE LEVEL) -70 dBm. Set step attenuators to 65 dB.

21.Adjust A4A5R54 SG20-2 for MKR A level of .OO dB. See

Figure 3-48 for location of adjustment.

Adjustments 3-89