VIRTUAL PATENT MARKING: FreqCheck™ technology is protected by U.S. Patent Application #19/422,049 (Filing Date: December 16, 2025). This page satisfies the virtual patent marking provisions of 35 U.S.C. § 287.
1. ISO/IEC 17025:2017 Calibration Certificate
The FreqCheck™ IND™ Signal Engine is validated against NIST-traceable standards. Accreditation Range: 4.0Hz to 100.0Hz.
2. IND™ Full Spectrum Sweep: 1Hz to 100Hz
The IND™ engine tracking a continuous tone sweep from 1Hz to 100Hz. This demonstration verifies signal lock and stability across the infrasonic spectrum independently of consumer hardware roll-off filters.
Unedited screen capture of the IND™ engine tracking a 1Hz - 100Hz reference signal.
3. IND™ Engine Technical Audit Case Study
This export report demonstrates the engine's ability to reconcile discrete spectral signatures across the infrasonic and gamma bands. Data derived from the 1Hz-100Hz verification sweep.
UNCERTAINTY DISCLOSURE: NIST-Traceable Systematic Quantization Limit ±0.67 Hz. Reported values reflect Fixed FFT Bin Centers (Bin Width 1.35 Hz @ 44.1kHz).
Verified Frequencies: 1Hz, 5Hz, 10Hz, 15Hz... 99.59Hz (Dominant: Gamma Band)
4. Metrological Traceability & Liability Disclaimer
Software Engine Verification: The FreqCheck™ DSP engine has been character-verified via direct electrical injection against ISO/IEC 17025 standards. This confirms mathematical accuracy within the specified range of 0.5 Hz to 100 Hz.
Hardware Chain Responsibility: FreqCheck™ is a software-based analytical tool. For accurate infrasonic measurements (below 20Hz), the use of a DC-Coupled Audio Interface is strictly required to prevent hardware-induced signal attenuation. Validity is contingent upon the calibration status of user-supplied sensors and interconnects.
5. Documented Systematic Digital Offsets
Due to the fixed bin width of 1.3458Hz in the Gamma band (30–100Hz), certain reference frequencies exhibit predictable shifts as the engine maps the peak signal to the nearest computational bin.
| Reference Input (Hz) | Bin Index | Bin Center (Hz) | Reported Value (Hz) | Systematic Offset |
|---|---|---|---|---|
| 33.00 | 25 | 33.64 | 34 | +1Hz |
| 40.00 | 30 | 40.37 | 40 | 0 |
| 45.00 | 33 | 44.41 | 44 | -1Hz |
| 60.00 | 45 | 60.56 | 61 | +1Hz |
| 80.00 | 59 | 79.40 | 79 | -1Hz |
| 86.00 | 64 | 86.13 | 86 | 0 |
| 95.00 | 71 | 95.55 | 96 | +1Hz |
| 100.00 | 74 | 99.59 | 100 | 0 |
Conclusion: These variances are systematic and non-random, confirming the engine operates at maximum theoretical resolution without artificial interpolation.
6. Hardware-Anchored Spectral Verification
Every FreqCheck™ Audit Report is protected by a three-layer integrity architecture. At the hardware level, a unique Device-Hash cryptographically anchors the report to the physical machine that generated it. At the document level, a SHA-256 cryptographic fingerprint is embedded at the moment of generation, creating an immutable checksum across every data point, timestamp, and verdict result. Finally, internal digital signing locks the PDF structure itself. Any post-generation modification, whether to spectral data, metadata, or a single character, instantly invalidates the document's internal checksum, detectable by any standard forensic PDF validator. The result is a forensic-grade, hardware-bound, tamper-evident audit record that cannot be falsified, backdated, or altered without immediate detection.