Condition: Used — Excellent condition, minimal usage, supplied as pictured.

The Spectrum Instruments TM4-M+ (Part No. 21351-102) is a GPS-disciplined Rubidium Time and Frequency Reference System. This unit is in excellent used condition with minimal usage. The TM4-M+ combines a rubidium atomic oscillator with GPS receiver disciplining to deliver highly accurate, UTC-traceable reference outputs with outstanding short- and long-term stability, suitable for standards laboratories, calibration benches, and communications test systems.

Included in the sale:
• Spectrum Instruments TM4-M+ Rubidium Time/Frequency Reference System (Part No. 21351-102) as pictured

The images provided are of the actual item you will receive. Please review them carefully for the cosmetic condition and what is included in the sale.

The Spectrum Instruments TM4-M+ is a Rubidium Time and Frequency Reference System designed for precision synchronisation, frequency calibration, and distribution in laboratory, telecoms, and field environments. The unit combines a rubidium atomic oscillator with GPS receiver disciplining to deliver a highly accurate, UTC-traceable reference output with excellent short- and long-term stability.

The GPS-disciplined rubidium oscillator ensures outputs remain locked to UTC, making it suitable for standards laboratories, calibration benches, communications test systems, and any application requiring a traceable 10 MHz reference signal. The system is capable of maintaining phase lock even in challenging GPS reception environments.

Spectrum's Intelligent Holdover technology learns the behaviour of the individual oscillator and uses that knowledge during periods of GPS unavailability to more precisely maintain stability. FastStart technology, coupled with a state-of-the-art GPS receiver, can have the unit operating at very high precision in as little as five minutes from startup.

Key Specifications:
Model: TM4-M+
Part Number: 21351-102
Oscillator Type: Rubidium atomic oscillator
Disciplining: GPS receiver disciplined
Primary Reference Output: 10 MHz
Timing Reference: UTC traceable
Holdover Technology: Intelligent Holdover (oscillator behaviour learning)
Startup Technology: FastStart (high precision within ~5 minutes)
Form Factor: Compact off-the-shelf module
Applications: Standards laboratories, frequency calibration, telecoms synchronisation, frequency distribution

Please refer to the Spectrum Instruments website for full and current specifications.

For the manufacturer datasheet, please click here

Note thsi is for the earlier TM4 model and so may notbe upto date

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Returns Policy

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