Chapter 3 3-49
Adjustments and Correction Constants
Fractional-N Spur Avoidance and FM Sideband Adjustment
Fractional-N Spur Avoidance and FM Sideband
Adjustment
Required Equipment and Tools
Analyzer warm-up time: 30 minutes.
This adjustment minimizes the spurs caused by the API (analog phase interpolator, on the
fractional-N assembly) circuits. It also improves the sideband characteristics.
1. Connect the equipment as shown in Figure 3-22.
2. Make sure the instruments are set to their default GPIB addresses:
8753ES/ET= 16, spectrum analyzer = 18.
Description HP/Agilent Part or Model Number
Spectrum analyzer 8563E
GPIB Cable 10833A/B/C/D
RF Cable: 50Ω, Type-N, 24-inch 8120-4781
Cable: 50Ω Coax, BNC (m) to BNC (m) 10503A
Non-metallic adjustment tool 8830-0024
Antistatic wrist strap 9300-1367
Antistatic wrist strap cord 9300-0980
Static-control table mat and ground wire 9300-0797
Additional Equipment for 50Ω Analyzers
Adapter APC-7 to Type-N (f)
(8753ES only)
11524A
Additional Equipment for 75Ω Analyzers
Minimum loss pad 11852B