Fractional-N Frequency Range Adjustment - Agilent Technologies 8753ES Option 011 Service Manual

Fractional-N Frequency Range Adjustment

This procedure centers the fractional-N VCO (voltage controlled oscillator) in its tuning
range to insure reliable operation of the instrument.
Analyzer warmup time: 30 minutes
Required Equipment and Tools
Description
Non-metallic adjustment tool
Antistatic wrist strap
Antistatic wrist strap cord
Static-control table mat and ground wire
TORX T-15 screwdriver
Procedure
1. Remove the right-rear bumpers and right side cover.
2. Press
Preset Display
SERVICE MENU
NUMBER OF POINTS
3. Press
Start 36
S PARAMETERS ANALOG IN Aux Input
k/m Meas
VCO Tun" voltage.
4. Press
MORE
Format
to set and scale channel 1. Press
x1
graticule.
5. Press
Chan 2 Sweep Setup
k/m Meas S PARAMETERS ANALOG IN Aux Input
VCO Tun" voltage.
6. Press
Format MORE
x1 Marker 6
7. Adjust the "FN VCO TUNE" (see
channel 1 marker is as many divisions above the reference line as the channel 2 marker
is below it. (See Figure
8. To fine-tune this adjustment, press
SERVICE MENU
"FRAC N TUNE" to 29.2 MHz.
Chapter 3
HP/Agilent Part Number
8830-0024
9300-1367
9300-0980
9300-0797
DUAL|QUAD SETUP DUAL CHAN ON
ANALOG BUS ON
COUPLED CH OFF
11 x1
M/µ Stop 60.75
REAL
Scale Ref
Marker
CW FREQ
REAL Scale Ref
to set channel 2 and its marker.
k/m
Figure
3-16.)
Preset
ANALOG BUS ON
Adjustments and Correction Constants
Fractional-N Frequency Range Adjustment
Sweep Setup
.
M/µ Sweep Setup
29
REFERENCE VALUE
.6 x1
to set the marker to the far right of the
31.0001 M/µ SWEEP TIME
29
.2 x1 REFERENCE VALUE
3-15) with a non-metallic tool so that the
CW FREQ
Sweep Setup
SERVICE MODES
System
SWEEP TIME
12.5
to observe the "FN
x1
−7
12.375
to observe the "FN
x1
6.77
System
to set
FRACN TUNE ON
3-39