Tracking Oscillator Range Centering - HP 8560A Service Manual

8. Record the frequency counter reading in Table 2-14 as Fl.
9.
On the HP 8560A, press
FINE TRACK ADJ is set to 255.
Record the frequency counter reading in Table 2-14 as F2.
10.
11. Calculate Fcenter as shown below and record in Table 2-14.
F
12. Set COARSE TRACK ADJ to 25. This sets the tracking oscillator near the center of its
frequency range (the relationship between the COARSE TRACK ADJ dac number and
the output frequency is nonlinear). Adjust COARSE TRACK ADJ and FINE TRACK
ADJ until the frequency counter reads Fcenter flO0 Hz.
13. Record the values of COARSE TRACK ADJ and FINE TRACK ADJ in Table 2-14.
14. Adjust AlOC3 TRK OSC CTR until the frequency counter reads 300 MHz f500 Hz.
15. Repeat steps 7 through 14 at least once more until no further adjustment of AlOC3 TRK
OSC CTR is necessary.
Set the HP 8560A LINE switch off. Replace the dust cap screw on AlO. Disconnect all
16.
cables from AlO.
17. Reinstall A10 in the HP 8560A.
Table 2-14. Tracking Oscillator Range Centering
20. Tracking Oscillator Adjustment (Option 002)
MAN TRK ADJ , (255), (Hz. Rotate
the knob clockwise until the
TRACK ADJ
Adjustment Procedures 2-73