The Anritsu Site Master S251C is a handheld, battery-operated 2-port cable and antenna analyzer designed specifically for tower top and duplex applications. Operating in the 625 MHz to 2500 MHz frequency range, it is optimized for field technicians working on cellular, PCS/GSM, and ISM systems. Featuring a second test port for isolation, gain, and insertion loss measurements, along with built-in FDR (Frequency Domain Reflectometry) technology for precise Distance-to-Fault analysis, the S251C provides high dynamic range and exceptional immunity to RF interference in active RF environments.

Specifications

General

ParameterValue
InterfacesRS232
Display640 x 480 monochrome LCD with backlight (standard) / TFT color display (Option 3 dependent)

Physical

ParameterValue
Power SupplyAC/DC power supply, 12.5 VDC automobile cigarette lighter adapter, or rechargeable battery
Operating Temperature-10 °C to 55 °C
Dimensions (W×H×D)300 x 178 x 80 mm
Weight1.8 kg (4 lbs) including battery

Frequency and Amplitude Performance

ParameterValue
Frequency Range625 MHz to 2500 MHz
RF Source Frequency Steps100 kHz steps

Vector Network Analysis Features

ParameterValue
Dynamic Range>90 dB (for antenna isolation measurements)
Selectable RF Output Power0 dBm or -30 dBm

Measurement Capabilities and Signal Processing

ParameterValue
RF Interference RejectionPatented RF interference rejection feature
Measurement ModesReturn loss, cable loss, distance-to-fault (DTF), VSWR power meter, isolation, gain, and insertion loss
Distance-to-Fault TechnologyFrequency Domain Reflectometry (FDR)
Display Markers6 markers, limit lines, and segmented limit lines
Cable DatabasePop-up menus featuring over 70 cable types with velocity of propagation and attenuation values
Power Monitor OptionOptional external power monitor compatibility
Bias Tee SupportOptional built-in Bias Tee
Distance UnitsSelectable feet and meters

System Architecture and Storage

ParameterValue
Saved Test SetupsUp to 10 measurement configurations
Saved Measurement TracesUp to 200 traces
Data LabelingAlphanumeric labeling with automatic time and date stamp
Multi-Language SupportEnglish, French, Chinese, Japanese, Spanish, German

Power and Electrical Specifications

ParameterValue
Battery CustomizationRechargeable, field-replaceable battery pack
Electrical ProtectionReverse, over voltage, and under voltage protection

Environmental

ParameterValue
Storage Temperature Range-20 °C to 75 °C
Maximum Operating Altitude4,500 m
Relative Humidity85% or less (non-condensing)

Performance

ParameterValue
Sweep Speed< 2.5 ms/data point (typical)
Data Points130, 259, 517
Directivity (Corrected)≥ 42 dB
Source Match (Corrected)≥ 30 dB
Load Match (Corrected)≥ 38 dB
System Impedance50 Ω
Return Loss Resolution0.01 dB
VSWR Resolution0.01

Frequency

ParameterValue
Frequency Accuracy±75 ppm
Frequency Resolution100 kHz

Inputs & Outputs

ParameterValue
Test Port ConnectorN-type, female, 50 Ω
RF In ConnectorN-type, female, 50 Ω

Electrical

ParameterValue
Maximum Input Damage Level+22 dBm, ±50 VDC

Technology

Frequency Domain Reflectometry (FDR)

Applications

Cellular, PCS/GSM, and ISM field testing, tower top and duplex system analysis, antenna-to-antenna isolation, and TMA gain verification