DIT DOTS KO6ETZ HAM RADIO • ELECTRONICS • SOFTWARE 14.074 MHz TX PWR RX
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Sorin Marghitoiu, KO6ETZ

Software Engineer · Consultant · Ham Radio · Indie Developer

I build radio control software, audio visualizers, and hardware projects, then put them all here. Over 20 years as a software engineer, including 17 years managing USC’s CiSoft lab and 7 as a Chevron consultant.

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Apps & Software

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ShackLink Server SDR display with 3D waterfall

ShackLink Suite

Free Windows Mobile Web

Control your ham radios from anywhere. Server with Morse/RTTY/PSK31/SSTV decoders, plus desktop, mobile, web, and Home Assistant clients.

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3D glass bars audio visualization

Stereo Spectrum Analyzer

$4.99 Windows Android iOS

40+ audio-reactive visualizations, built-in music player, 30,000+ internet radio stations, and a shader sandbox.

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Intimate Connection dashboard showing mood matching between partners

Intimate Connection

$4.99 iOS Android Windows

Private mood-sharing for couples. AES-256-GCM encrypted, local WiFi only. No servers, no accounts, no data harvesting.

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From the Workbench

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Rohde and Schwarz CMU200 communication tester on workbench

Fixing a Rohde & Schwarz CMU200/300

Taking a broken universal radio communication tester from eBay and bringing it back to life.

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Anritsu MD8475A signaling tester

Repurposing an Anritsu MD8475A

A cellular signaling tester designed for base station testing, now repurposed for radio experimentation.

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ESP32-S3 remote control knob with LVGL touchscreen

ESP32-S3 Remote Control Knob

Custom hardware controller with LVGL touchscreen UI, WiFi, and TCP connection to ShackLink Server. Tune from across the room.

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Petroleum Software

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Decline Analysis showing a fitted harmonic decline curve over a multi-series well production history

Decline Analysis

Fits exponential, harmonic and hyperbolic decline curves to irregular well production histories, driving scipy differential evolution from a VB.NET front end.

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Voronoi Diagram Generator showing a distance heat map over point and line-segment seeds

Voronoi Drainage Engine

Weighted and line-segment Voronoi diagrams for drainage and catchment areas, one tested core running on the desktop and in the browser via WebAssembly.

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Interwell Connectivity prediction tab showing per-producer influence decomposed by injector

Interwell Connectivity

Quantifies which injector feeds which producer across a waterflood, using an FIR capacitance model behind an eight-project multi-tier .NET platform.

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What I’m Working On

Last updated: July 2026

  • Shipped Stereo Spectrum Analyzer v2: 40+ visualizations, built-in player, internet radio, SKSL shader sandbox, network media browsing.
  • Shipped Spectra Media Player: Mobile version for Android & iOS with 37+ visualizations, 62 shader presets, and molecule structures from PubChem.
  • Active ShackLink SSTV decoder: Adding support for Robot, Martin, Scottie, PD, Wraase, and Pasokon modes.
  • Ongoing ShackLink Suite: Ongoing development of the remote radio-control ecosystem: server, decoders, SDR features, and desktop, mobile, web, and Home Assistant clients.
  • Ongoing Lumea Vidă translation: Translating my father’s philosophical treatise “The Void World” from Romanian to English. ~9% complete.