HP 8568B, Руководство по испытаниям и регулировке работы, Страница: 231 / 313

17. Pilot Second IF Amplifier Adjustments
Procedure
1. Position instrument on right side as shown in Figure 3-67, with
bottom cover removed.
2. Set LINE switch to ON and press
PRESET
)
on HP
(DUT), HP and HP
3. Connect 20 Attenuator and power splitter to RF OUTPUT of
synthesized sweeper. Connect one arm of power splitter to R
input of scalar network analyzer through detector as shown in
Figure 3-67.
4. Set synthesized sweeper FREQUENCY MARKERS to 254 MHz
and to 284 MHz.
5. Press 269 MHz on synthesized sweeper.
6. Connect Power Meter to the other power splitter port and set
synthesized sweeper
LEVEL
)
for a Power Meter indication
of -20.0
7. Disconnect Power Meter and connect power splitter output to
using adapter and BNC to SMB test cable.
8. Connect to A input of scalar network analyzer through
detector, using adapter and another BNC to SMB test cable.
9. Connect synthesized sweeper SWEEP OUTPUT (rear panel),
Z-AXIS BLANK/MKRS (rear panel), and PULSE MODULATION
INPUT (front panel) to proper rear-panel connectors on scalar
network analyzer, shown in Figure 3-67.
10. On scalar network analyzer, turn channel 2 off and press
(A/R).
11. Set the scalar network analyzer to 1 and set (REF
LEVEL) to + 10.00 Set REF POSN (press REF POSN) to the
fourth division from the bottom using the data knob.
12. On synthesized sweeper, press (ON),
SWEEP
),
and
Set SWEEP TIME to 500 ms.
13. Adjust REF LEVEL for a mid-screen response of signal on HP
14. Adjust 269 MHz Filter, and
for best filter response with gain of greater
than + 10 (above REF 1 line). See Figure 3-68 for location
of adjustments. Figure 3-69 shows typical response when the
filter is properly adjusted.
Adjustments 17