About FMTLab

FMTLab (Frequency and Time Measurement Laboratory) is a precision measurement platform for amateur radio operators, focused on carrier frequency accuracy, pulse timing analysis, and long-term signal stability observations.

Project Overview

FMTLab operates a GPS-disciplined HF beacon transmitting calibrated signals from Warsaw, Poland. Amateur radio operators worldwide compete to measure carrier frequency (sub-Hz accuracy), pulse timing (ms precision), and PPS synchronization with maximum precision, then submit results through this web portal. The platform combines competitive scoring with long-term dataset collection, where ionospheric variability and propagation conditions add unpredictability that makes each measurement session unique.

What Makes FMTLab Unique

Competition meets precision measurement

FMT transforms frequency metrology from a lab discipline into a competitive challenge. Operators worldwide compete for sub-Hz accuracy rankings, driving continuous improvement in equipment, techniques, and understanding of RF propagation.

Natural phenomena as the wild card

Unlike controlled lab measurements, FMT signals traverse variable ionospheric paths. Doppler shifts from moving plasma, multipath interference, and atmospheric noise create measurement challenges that change hour by hour. This variability is not a flaw—it's the essence of the contest, where skill meets unpredictable physics.

Long-term data, seasonal patterns

Multi-season participation reveals propagation trends: solar cycle effects, seasonal ionospheric changes, diurnal variations. Competitors who study these patterns gain competitive advantage while contributing to citizen science datasets.

Open methodology, reproducible results

All reference values, scoring algorithms, and beacon calibration data are published. The playing field is transparent: success depends on measurement skill and equipment quality, not insider knowledge.

Project Ownership

Konstantin Lisitsyn (SP5LST)

Project coordinator and owner
Full responsibility for platform architecture, measurement methodology, system operation, and long-term continuity
Warsaw, Poland

Core Roles

Konstantin Lisitsyn (SP5LST)

Coordinator
System architecture · Measurement methodology · Platform operation · HF beacon engineering

Technical Consulting

Alex Lisitsyn (RU0LL)

Author of the original FMTLab contest format
Signal analysis and RF technical consulting
Initiated and practically applied the FMT contest methodology. Involved since early conceptual phase. Provides RF propagation and signal processing guidance.

Contributors

The project benefits from testing, feedback, and technical contributions provided by radio operators and engineers worldwide.

Andreas (DJ3EI)

Documentation feedback and community support
Review of public documentation and schedule-page clarity
Receiver-side feedback based on spectrum observations and typical station setups
Suggestions to reduce ambiguity for first-time participants

Operating Principles

  • Measurements are primary: All conclusions must be backed by quantified data from calibrated equipment
  • Reproducibility: Measurement procedures and calibration chains are documented and repeatable
  • Conservative interpretation: Uncertainty is acknowledged; claims stay within validated accuracy bounds
  • Long-term data: Multi-season datasets enable propagation studies and temporal analysis
  • Controlled methodology: Beacon hardware, transmission schedules, and scoring rules are version-controlled
  • Transparency: Scoring algorithms, reference values, and participant rankings are publicly accessible
  • Competition drives learning: Ranking and scoring motivate operators to refine techniques, upgrade equipment, and study propagation effects
  • Nature adds challenge: Ionospheric variability, multipath, Doppler shifts, and atmospheric noise introduce unpredictability that makes precision measurement a continuous pursuit rather than a solved problem

Technical Infrastructure

The Warsaw station operates a GPS-disciplined transmit/receive chain with sub-Hz frequency stability and ms-level timing accuracy. Equipment includes HP synthesizers, Icom/Kenwood transceivers, Keysight pulse generators, and automated control via Raspberry Pi 5. Full equipment specifications and calibration procedures are documented below.

Synchronization and references

  • GPSDO: BG7TBL (10 MHz + 1 PPS) disciplining the entire chain
  • Target accuracy: sub-Hz carrier stability; pulse alignment to UTC seconds after calibrated delay compensation

Signal modes

  • Carrier mode: HP 3336A synthesizer (GPS-locked) drives the IC-7300 PA through band-filters for spectral cleanliness
  • Pulse mode: IC-7300 in USB; pulses triggered by 1 PPS with calibrated AD/DA delay correction

RF chain & control

  • Antenna: ~40 m end-fed at ~20 m AGL
  • Receiver: Kenwood TS-890S locked to GPSDO
  • Pulse source: Keysight EDU33211A into IC-7300 (SSB)
  • Switching & automation: custom low-level RF/AF switching controlled by Raspberry Pi 5 (automatic scheduling, mode control)

Measurement instruments

  • Oscilloscope: R&S RTB2002
  • Frequency counter: Agilent 53131A

Operations

  • Routine calibration runs vs. standard-frequency services (e.g., RWM, PCSK225 from Solec Kujawski)
  • Data retention and post-analysis to support scoring, peer review, and method improvement

Contact & Responsibility

General contact:
[email protected]

Coordinator:
[email protected]