Agilent/Keysight Z3805A

The Agilent/Keysight Z3805A is a GPS time and frequency reference receiver that delivers traceable synchronization and frequency stability for precision-critical applications. It combines an 8-channel GPS receiver with a double oven ultra-precision oscillator to achieve frequency accuracy better than 1 × 10⁻¹² when locked to GPS, with annual time base stability of 1.5 × 10⁻¹² per year. The instrument maintains system synchronization for up to 24 hours in holdover mode when satellite signals are unavailable.

Technical Specifications

• GPS Receiver: 8-channel receive, 6-channel parallel tracking; C/A code, L1 carrier


• Frequency Accuracy: Better than 1 × 10⁻¹² (GPS locked)


• Time Base Stability: 1.5 × 10⁻¹² per year


• Holdover Duration: 24 hours maximum with reduced accuracy


• Internal Oscillator: HP 10811-60165 double oven ultra-precision high stability oscillator


• Output Signals: Two 10 MHz outputs; two 1 PPS outputs


• Power Input: 19.5 – 30 V DC; approximately 1.09 A at 24 V DC (GPS locked)


• Connectors: Type-N female antenna (with +5 V supply for amplified antennas); DB-25 female data interface; XLR audio connector for power

Key Features

• Dual 10 MHz and PPS outputs for multi-system synchronization


• RS-232 and SCPI command interface via dual DB-25 ports (Port 1: SCPI control; Port 2: Time of Day output)


• Active antenna support with integral bias voltage


• Low power consumption enables integration into battery-backed or remote installations

Typical Applications

• Telecommunications network synchronization


• Frequency calibration laboratories and metrology


• Precision timing systems requiring holdover capability

Compatibility & Integration Responds to SCPI (Standard Commands for Programmable Instruments) protocol. Compatible with software platforms including Lady Heather, SatStat, and GPScon. Accepts DC power supplies within the 19.5 – 30 V DC range.