Updates to the ST-LINE technical pages: calculation method, assumptions, validity conditions and regulatory references. The wikis are living content: a standard changing edition is an update.https://www.stline.it/en-UShttps://www.stline.it/en/wiki/raysound/https://www.stline.it/en/wiki/raysound/What ST-LINE's proprietary engine for enclosed-space acoustics does: per-band prediction, inverse design from a target to the surface treatment, and an upfront diagnosis of how much the available data can actually determine. — updated 2026-09-02, published 2026-08-25.Wed, 02 Sep 2026 00:00:00 GMTacusticaRoom acousticsAcoustic designCAM 2025UNI 11532Inverse designBRASinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/riferimenti-normativi-acustica/https://www.stline.it/en/wiki/riferimenti-normativi-acustica/The Italian statutes and the ISO, IEC and UNI standards in force for environmental and building acoustics, each with its edition, scope, and what it does NOT cover. — published 2026-08-26.Wed, 26 Aug 2026 00:00:00 GMTacusticaRegulationISOIECUNILaw 447/95DPCM 5/12/1997info@stline.it (ST-LINE)https://www.stline.it/en/wiki/vibrazioni-edifici/https://www.stline.it/en/wiki/vibrazioni-edifici/Four different questions, four different standards: disturbance to people, damage to the building, worker exposure, sensitive equipment. Conflating them is the commonest mistake. — published 2026-08-26.Wed, 26 Aug 2026 00:00:00 GMTacusticaVibrationUNI 9614UNI 9916ISO 2631D.Lgs 81/08IEPE accelerometersinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/acmap/https://www.stline.it/en/wiki/acmap/Browser-based acoustic mapping: sound-level surveys and a simplified octave-band propagation model, with ISO 9613 terms and Maekawa diffraction on OSM buildings. — updated 2026-08-25, published 2026-05-20.Tue, 25 Aug 2026 00:00:00 GMTacusticaJavaScriptLeafletISO 9613-2MaekawaOpenStreetMapApache-2.0info@stline.it (ST-LINE)https://www.stline.it/en/wiki/adc-dac-snr/https://www.stline.it/en/wiki/adc-dac-snr/Quantization and LSB size, where 6.02·N+1.76 comes from, SINAD and ENOB as the real figure of merit, dynamic range and the Nyquist frequency. — updated 2026-08-25, published 2026-06-24.Tue, 25 Aug 2026 00:00:00 GMTelettronicaADCDACSNRENOBResolutioninfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/analog-filter-bode/https://www.stline.it/en/wiki/analog-filter-bode/1st- and 2nd-order filters — RC, RL, RLC and Sallen-Key — cutoff frequency and Q factor, how to read a Bode plot and why you move to an active topology. — updated 2026-08-25, published 2026-06-23.Tue, 25 Aug 2026 00:00:00 GMTelettronicaFiltersRCRLCSallen-KeyBodeinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/arducam-evk-gui/https://www.stline.it/en/wiki/arducam-evk-gui/Tkinter GUI for the Arducam EVK SDK, sensor data-driven. — updated 2026-08-25, published 2026-05-20.Tue, 25 Aug 2026 00:00:00 GMTelettronicaPython 3.8+ · TkinterOpenCV · NumPyArducam EVK SDK 1.0.7MITinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/crystal-load-cap/https://www.stline.it/en/wiki/crystal-load-cap/What a crystal's load capacitance CL is, why the two external capacitors are needed, how to size them from the stray capacitance, and what happens when the value is wrong. — updated 2026-08-25, published 2026-06-23.Tue, 25 Aug 2026 00:00:00 GMTelettronicaCrystalOscillatorLoad CapacitanceClockEMCinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/data-format-inspector/https://www.stline.it/en/wiki/data-format-inspector/How the same bytes become different numbers — big/little endianness, two's-complement integers, IEEE-754 single/double floats (sign, biased exponent, mantissa) and the practical cases of reading registers and binary frames. — updated 2026-08-25, published 2026-06-24.Tue, 25 Aug 2026 00:00:00 GMTsoftwareEndiannessIEEE 754HexData typesInstrumentationinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/fft-window-explorer/https://www.stline.it/en/wiki/fft-window-explorer/Spectral leakage, windows (Hann, Hamming, Blackman, Blackman-Harris, flat-top) and their metrics — ENBW, scalloping, main lobe and side-lobes — how to pick the right window to analyse a spectrum. — updated 2026-08-25, published 2026-06-24.Tue, 25 Aug 2026 00:00:00 GMTsoftwareFFTDSPWindowSpectrumSignal analysisinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/gerber-viewer/https://www.stline.it/en/wiki/gerber-viewer/What the Gerber format is and where it comes from, its variants (RS-274D, RS-274X, X2), the Excellon drill file, how a PCB's layers compose and why many manufacturers today prefer formats like ODB++ and IPC-2581. — updated 2026-08-25, published 2026-06-24.Tue, 25 Aug 2026 00:00:00 GMTelettronicaGerberPCBViewerLayerEDAinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/iir-filter-designer/https://www.stline.it/en/wiki/iir-filter-designer/Designing IIR filters in the five classical families (Butterworth, Chebyshev I and II, elliptic, Bessel) as a cascade of second-order sections: bilinear transform, stability from the poles, SOS coefficients and CMSIS-DSP export. — updated 2026-08-25, published 2026-06-24.Tue, 25 Aug 2026 00:00:00 GMTelettronicaIIRBiquadSOSDSPCMSIS-DSPinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/image-processing-lab/https://www.stline.it/en/wiki/image-processing-lab/The fundamentals behind the Image Processing Lab tool: 2D convolution and kernels, the Bayer pattern of CMOS sensors and demosaicing, histogram, luminance and exposure. — updated 2026-08-25, published 2026-06-24.Tue, 25 Aug 2026 00:00:00 GMTsoftwareImage processingConvolutionBayerDemosaicHistograminfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/italian-road-noise-limits/https://www.stline.it/en/wiki/italian-road-noise-limits/Pre-screening against the Italian DPR 142/04: noise-pertinence bands, limits for new, existing and assimilated roads, sensitive receptors. — updated 2026-08-25, published 2026-05-21.Tue, 25 Aug 2026 00:00:00 GMTacusticaEnvironmental acousticsDPR 142/04Road noisePertinence bandsItalyinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/lex-8h/https://www.stline.it/en/wiki/lex-8h/A worker's daily personal noise exposure level and the action and limit values of the Italian Workplace Safety Act. — updated 2026-08-25, published 2026-05-21.Tue, 25 Aug 2026 00:00:00 GMTacusticaWorkplace safetyD.Lgs 81/08LEX,8hNoiseItalyinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/maekawa/https://www.stline.it/en/wiki/maekawa/Why sound is still heard behind a noise barrier: geometry, Fresnel number and single-edge attenuation. — updated 2026-08-25, published 2026-05-21.Tue, 25 Aug 2026 00:00:00 GMTacusticaAcousticsDiffractionMaekawaISO 9613-2Fresnel numberinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/measurement-uncertainty/https://www.stline.it/en/wiki/measurement-uncertainty/An uncertainty budget per the GUM — type A and B uncertainty, distributions and divisors (√3 rectangular, √6 triangular), combination in quadrature, expanded uncertainty and the coverage factor. — updated 2026-08-25, published 2026-06-24.Tue, 25 Aug 2026 00:00:00 GMTsoftwareGUMUncertaintyMeasurementMetrologyType A/Binfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/mipi-csi2-bandwidth/https://www.stline.it/en/wiki/mipi-csi2-bandwidth/How to size the link between a camera sensor and a SoC: from pixel rate to data rate, D-PHY lane utilization, pixel formats and packetization overhead. — updated 2026-08-25, published 2026-06-23.Tue, 25 Aug 2026 00:00:00 GMTelettronicaMIPICSI-2D-PHYCameraImaginginfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/noise-barrier-calc/https://www.stline.it/en/wiki/noise-barrier-calc/Noise-barrier attenuation calculator: ISO 9613-2 §7.4 + Maekawa selectable, per octave band. Live tool at /en/tools/barrier-calculator/. — updated 2026-08-25, published 2026-05-20.Tue, 25 Aug 2026 00:00:00 GMTacusticaJavaScriptLeafletISO 9613-2MaekawaNoise barrierApache-2.0info@stline.it (ST-LINE)https://www.stline.it/en/wiki/pcb-trace-designer/https://www.stline.it/en/wiki/pcb-trace-designer/Sizing the traces of a printed circuit board: width for current capacity (IPC-2221), resistance and voltage drop; the characteristic impedance of microstrip and stripline and why it matters for signal integrity. — updated 2026-08-25, published 2026-06-24.Tue, 25 Aug 2026 00:00:00 GMTelettronicaPCBIPC-2221ImpedanceMicrostripSignal integrityinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/pdn-decoupling/https://www.stline.it/en/wiki/pdn-decoupling/Power distribution network, target impedance Zt = ΔV/ΔI, the role of bulk and HF capacitors, anti-resonance and how to choose values to keep the rail impedance low. — updated 2026-08-25, published 2026-06-24.Tue, 25 Aug 2026 00:00:00 GMTelettronicaPDNDecouplingPower integrityCapacitorsImpedanceinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/pffdtd/https://www.stline.it/en/wiki/pffdtd/The ST-LINE fork of Brian Hamilton's FDTD solver: how a grid-based wave forward works, what it costs, where staircasing breaks it, and what was optimised on the CUDA engine while leaving the numerical scheme untouched. — updated 2026-08-25, published 2026-06-25.Tue, 25 Aug 2026 00:00:00 GMTacusticaRoom acousticsFDTDDiscontinuous GalerkinGPU CUDABRASInverse designinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/reverberation-time/https://www.stline.it/en/wiki/reverberation-time/Reverberation in enclosed spaces: what it is, why it matters, how it is measured, how it is reduced and when treatment really helps. — updated 2026-08-25, published 2026-05-21.Tue, 25 Aug 2026 00:00:00 GMTacusticaBuilding acousticsReverberationT60ISO 3382-2SabineAcoustic treatmentinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/simulatore-sala/https://www.stline.it/en/wiki/simulatore-sala/Clarity and reverberation in a rectangular room: exact Image Source Method, Eyring/Sabine diffuse tail, and why C50/C80/EDT/T30 describe listening quality. — updated 2026-08-25, published 2026-06-19.Tue, 25 Aug 2026 00:00:00 GMTacusticaBuilding acousticsImage Source MethodC50C80EDTT30Eyringinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/uart-baud-error/https://www.stline.it/en/wiki/uart-baud-error/How a UART generates the baud by dividing the clock, why an error appears, how the tolerance budget is derived (3.95% for 8N1 at 16×) and the role of the fractional divisor. — updated 2026-08-25, published 2026-06-23.Tue, 25 Aug 2026 00:00:00 GMTelettronicaUARTBaud rateSerialMCUClockinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/usb-pd-pdo/https://www.stline.it/en/wiki/usb-pd-pdo/How a USB-C charger declares what it can supply: the 32 bits of the Power Data Object, the field scaling, and the sink↔source negotiation that takes you from the initial 5 V to the power contract. — updated 2026-08-25, published 2026-06-23.Tue, 25 Aug 2026 00:00:00 GMTelettronicaUSB-PDPDOUSB Type-CPPSEPRinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/usbpd-stack/https://www.stline.it/en/wiki/usbpd-stack/Cross-platform distribution of the NXP USB Power Delivery stack for the PTN5110. — updated 2026-08-25, published 2026-05-20.Tue, 25 Aug 2026 00:00:00 GMTelettronicaESP32-S3 · STM32 · ArduinoCPD 2.0 / 3.0PTN5110 TCPCBSD-3 + MITinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/visualdb/https://www.stline.it/en/wiki/visualdb/Local app to build forms, sheets and reports over existing databases, no cloud. — updated 2026-08-25, published 2026-08-24.Tue, 25 Aug 2026 00:00:00 GMTsoftwarePython 3.11+ · NiceGUISQLAlchemy 2.0PostgreSQL · MySQL · SQL Server · Oracle · SQLite · DuckDBMITinfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/x-cube-n6-camera-capture-nucleo/https://www.stline.it/en/wiki/x-cube-n6-camera-capture-nucleo/Exploring the STM32N6: a UVC webcam with the hardware H.264 encoder. — updated 2026-08-25, published 2026-05-20.Tue, 25 Aug 2026 00:00:00 GMTelettronicaSTM32N6 · Cortex-M55H.264 HW encoderMIPI-CSI2 + ISPFreeRTOS + USBXCMake / Ninjainfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/composizione-livelli/https://www.stline.it/en/wiki/composizione-livelli/Adding and subtracting levels in decibels: why 60 + 60 dB make 63 and not 120, and how to correct a measurement for background noise. — updated 2026-08-24, published 2026-05-21.Mon, 24 Aug 2026 00:00:00 GMTacusticaAcousticsDecibelsISO 1996-2Energetic suminfo@stline.it (ST-LINE)https://www.stline.it/en/wiki/criterio-differenziale/https://www.stline.it/en/wiki/criterio-differenziale/The Italian check that noise from a specific source does not exceed the background by more than 5 dB by day and 3 dB by night, inside the affected dwelling. — updated 2026-08-24, published 2026-05-21.Mon, 24 Aug 2026 00:00:00 GMTacusticaEnvironmental acousticsL. 447/95DPCM 14/11/97Differential criterionItalyinfo@stline.it (ST-LINE)