Building a satellite tracker in the browser
How I built a real-time amateur radio satellite tracker using TLE data, SGP4 propagation, and Leaflet — with pass predictions and frequency info for 8 satellites.
Skip Zone
Amateur radio for everyone.
latest posts
Getting on a VHF/UHF repeater: offsets, tones, and your first QSO
Repeaters extend your range dramatically — but programming one into your radio for the first time is a rite of passage. Here's how offsets, CTCSS tones, and repeater etiquette actually work.
Building a CW decoder in the browser — and what comes next
How I built a real-time Morse decoder using the Web Audio API, Goertzel filters, and AudioWorklets — and why the next version will move the heavy lifting to a Python backend.
tools
live
all tools → CW decoder
Real-time Morse decoder with Goertzel filter tone detection. Feed audio from your radio or microphone — adaptive timing with WPM range control.
liveCW trainer
Browser-based Morse code trainer. Set speed, length, and character set — listen and decode. No account required.
liveSatellite tracker
Track amateur radio satellites in real time — ISS, SO-50, AO-91, and more. Pass predictions with frequency and CTCSS info.
coming soon
Logbook
Lightweight QSO log with ADIF export. No account required. Data stays in your browser.
references
live
all references → Morse reference
Complete Morse code chart — letters, numbers, punctuation, prosigns, Q-codes, and common CW abbreviations.
livePhonetic alphabet
Convert callsigns and text to NATO phonetic spelling. Full reference chart included.
about
Skip Zone is written and built by MM7IUY ( Cam ) — a newly licensed Foundation holder in Scotland and software engineer by day. The name is inspired by RF propagation: the dead zone between a transmitter and where its signal returns to Earth. Most amateur radio content skips straight over the people who'd find it most interesting. This is for them.
more →