HP / Agilent 5383A 520 MHz Frequency Counter

The HP/Agilent 5383A is a direct-counting frequency counter delivering precise measurements from 10 Hz to 520 MHz. This benchtop instrument combines a nine-digit LED display with selectable gate times, dual input impedances, and attenuator options to support diverse measurement scenarios in electronics testing, communications, and RF applications. The counter measures frequency, period, and totalize functions with 1 Hz resolution and ±1 count ± time base accuracy across its full range.

## Technical Specifications

Frequency measurement spans 10 Hz to 520 MHz with 1 Hz resolution per second of gate time. The nine-digit LED display includes an overflow indicator for out-of-range signals. Accuracy is ±1 count ± time base accuracy, with internal time base stability at ±1 ppm. Option 001 upgrades the oscillator to a temperature-compensated crystal (TCXO) for enhanced long-term stability.

Input impedance selections are 1 MΩ (X1, X10) or 50 Ω. Sensitivity varies by impedance and frequency: 1 MΩ input requires 25 mV rms from 10 Hz to 10 MHz and 50 mV rms from 10 MHz to 520 MHz; 50 Ω input requires 25 mV rms across the full 10 Hz to 520 MHz range. Maximum input voltage is 250 V RMS, with fuse protection on the 50 Ω channel.

Gate time is selectable between 0.1 s, 1 s, and 10 s. The internal time base oscillator may be monitored or replaced via rear panel connector. With Option 001, the rear connector functions exclusively as a monitor point.

## Key Features

• Nine-digit LED display with overflow indicator
• Dual input impedance (1 MΩ and 50 Ω) for flexible signal coupling
• Three measurement functions: frequency, period, and totalize
• Selectable gate times from 0.1 s to 10 s
• External or internal time base reference capability
• Compact form factor: 89 mm H × 160 mm W × 248 mm D; 2.2 kg net weight
• Wide power acceptance: 90 V to 252 V rms, 48 Hz to 440 Hz
• Low power consumption: 30 VA maximum

## Typical Applications

Frequency verification and characterization in RF component testing, communications equipment commissioning, and broadcast signal monitoring where direct-count accuracy and rapid measurement cycles are essential.

## Compatibility & Integration

Rack mounting kits available: 10851A (single unit) and 10852A (dual unit side-by-side installation). Operating temperature range is 0°C to 40°C; storage rated to -40°C to 70°C.