jcalado.com

IASDCG

Joel Calado — Mon, 20 Jan 2020 00:00:00 GMT

IASDCG

IASDCG was my first ever C# WPF app and it was used to control CasparCG servers, with features tailored for local Seventh-day Adventist Churches.

Preview

CGTimer

Joel Calado — Sat, 02 Jan 2021 00:00:00 GMT

CGTimer

CGTimer is an Electron app to display current video time from a CasparCG server instance.

Features

Displays active clip current time
Displays remaining clip time
Starts flashing red at less than 5 seconds to clip end
Warns about video being looped, via a red "L" on the clip time panel
When CasparCG is issued a STOP command to the ffmpeg producer, everything is reset

Preview

Source Code

View the project on GitHub

Hyperdeckctl

Joel Calado — Sat, 02 Jan 2021 00:00:00 GMT

Hyperdeckctl

Hyperdeckctl allows you to trigger common functions of your Blackmagic Design Hyperdeck recorders from a single interface.

Preview

Source Code

View the project on GitHub

VDO.Ninja invite generator

Joel Calado — Sat, 05 Jun 2021 00:00:00 GMT

VDON-invite

Generates VDO.Ninja invites tailored to the user preferences by toggling switches on or off.

Features

Expanding panel UI
Popover information
Loads data from external JSON file, allowing for complete reorder of toggles
Generates additional VDO.Ninja director page URL when appropriate
Generates custom view links
Click to copy URLs
Optionally obfuscates links via invite.cam

Source Code

View the project on GitHub

Semáforo de Vacinação COVID

Joel Calado — Sun, 11 Jul 2021 00:00:00 GMT

Semáforo de Vacinação COVID - Mobile App

This React Native app consumes the same data as covid19.min-saude.pt/cvc and presents it in a friendly manner.

It is my first React Native app, so some things might not be 100% up to standard.

Features

Downloads real-time data from the API endpoint
Searches by location or center name
Shows a map with API-provided markers so you can have a sense of scale. There are a lot of centers!
Displays how old the API-provided data is, so the user is not misled
Provides undocumented stats such as "Pessoas em recobro", "Pessoas em espera"
Pull down to refresh data

Screenshots

Source Code

View the project on GitHub

Environmental quality sensors - CML

Joel Calado — Sat, 17 Jul 2021 00:00:00 GMT

Environmental Quality Sensors - Câmara Municipal de Lisboa

A React application that displays environmental quality sensor data from Lisbon's public API in an interactive data table.

Live Demo: jcalado.com/sensores-qa-cml

Screenshot

Features

Search by Sensor name
Search by Category name
Search by Station
Some sensors have colored thresholds in place: low, medium, high, danger, extreme
Every column is sortable

Technical Notes

Requests are proxied through allorigins.win, since the original API URL has CORS issues.

Metadata Info

There's some information about the API published here: Metadata

APOD

Joel Calado — Tue, 17 Aug 2021 00:00:00 GMT

import GooglePlayButton from '~/components/GooglePlayButton.astro'

APOD

APOD stands for "Astronomy Picture Of the Day".

App download

Screenshot

Features

Today's APOD
Last 90 days worth of APODs
Get a random APOD
Share
Support for videos and other web content

HeidiSQL Password Decoder: A Secure Client-Side Recovery Tool

Joel Calado — Sun, 23 Mar 2025 00:00:00 GMT

🔐 HeidiSQL Password Decoder

I'm excited to share a new tool I've built that solves a common problem for database administrators who use HeidiSQL. Have you ever found yourself in a situation where you need to recover a database password from your HeidiSQL connection settings? Maybe you're migrating to a new system or just need to share credentials with a colleague. That's exactly why I created the HeidiSQL Password Decoder.

Live Demo: jcalado.com/heidisql_password_decoder

The Problem

HeidiSQL is a fantastic database management tool, but it stores your passwords in an encoded format in its settings file. While this isn't true encryption (and isn't meant to be), it does prevent casual viewing of your passwords. When you need those passwords outside of HeidiSQL, you're typically out of luck.

The Solution

This browser-based tool uses the same algorithm that HeidiSQL employs to encode/decode passwords but runs entirely in your browser. No data ever leaves your computer, making it a secure way to retrieve those passwords when you need them.

✨ Key Features

🔒 100% Client-side Processing: All decoding happens in your browser - no data is ever sent to a server
🖥️ Clean Modern Interface: Intuitive design with visual feedback
📋 Easy Copy Functionality: One-click copy for decoded passwords
🔍 Smart Detection: Automatically finds password entries in your settings file
🌐 Works Offline: No internet connection required after initial page load

📋 How to Use It

The tool is designed to be as simple as possible:

Export your HeidiSQL connection settings or copy from your sessions file
Paste the contents into the text area
Click "Decode Passwords"
View all your server connections and their decoded passwords
Copy any password with a single click

🔍 Behind the Scenes

HeidiSQL's password encoding is relatively straightforward. The encoded password format ends with a digit that indicates the shift value used in the encoding. Here's the JavaScript function that powers the decoding:

function heidiDecode(hex) {
    var str = '';
    var shift = parseInt(hex.substr(-1));
    hex = hex.substr(0, hex.length - 1);
    for (var i = 0; i < hex.length; i += 2)
        str += String.fromCharCode(parseInt(hex.substr(i, 2), 16) - shift);
    return str;
}

The algorithm works like this:

It takes the last character of the encoded string as a "shift" value
It processes the rest of the string in pairs of characters, treating them as hexadecimal values
It converts each hex pair to a character code, subtracts the shift value, and converts to the corresponding character
The resulting string is the original password

🔒 Privacy Considerations

When dealing with passwords, security is paramount. This tool was built with privacy as the top priority:

No data is ever sent to any server
All processing happens directly in your browser
No cookies or local storage used
No analytics or tracking
No external requests after page load

Why Build This?

As a developer who works with databases frequently, I've encountered situations where I needed to recover a HeidiSQL password. Rather than writing a quick script each time, I decided to build a proper tool that others might find useful as well.

The project also gave me a chance to practice creating a focused, security-conscious web application that respects user privacy while solving a specific problem.

What's Next?

While the tool is fully functional as is, I'm considering adding support for additional database tools that use similar encoding methods. If you have suggestions or feature requests, feel free to reach out or contribute to the project.

Source Code

View the project on GitHub

Repetidores - Portugal Amateur Radio Repeater Directory

Joel Calado — Fri, 24 Oct 2025 00:00:00 GMT

Repetidores - Your Complete Amateur Radio Companion for Portugal

Update: Repetidores has moved! The application is now available at radioamador.info. All features and functionality remain and there's so much more at the new domain.

Repetidores is an all-in-one Progressive Web App for Portuguese amateur radio operators. Instead of juggling multiple websites and resources, Repetidores brings together everything you need in one place: repeater data, band plan information, and upcoming ham radio events.

The Problem

Amateur radio operators in Portugal were dealing with fragmented information scattered across multiple sources. Finding repeater details meant one website, checking band plans required another, and discovering local events meant searching through various channels. Whether you're planning a trip, setting up your radio equipment, or looking for the next ham radio gathering, having to consult multiple resources is inefficient and frustrating.

The Solution: A One-Stop-Shop for Ham Radio in Portugal

Repetidores consolidates the essential resources Portuguese amateur radio operators need into a single, modern platform. With over 190 repeaters in the database, comprehensive band plan information, and an events calendar, you can access everything from one convenient location.

The application combines powerful search and filtering with interactive visualization, giving operators both the detailed technical specifications they need and the geographic context to make informed decisions.

Three Essential Resources in One Place

1. Comprehensive Repeater Database

Access detailed information on over 190 repeaters across Portugal, including mainland, Azores, and Madeira regions.

Search and filter repeaters
Show them on a map
Copy repeater data easily - single click
Export to Chirp-compatible CSV.

2. Band Plan Information

No need to search elsewhere for frequency allocations and band plan details. Repetidores includes a dedicated bands section with comprehensive frequency information, making it easy to understand which frequencies you can use and for what purposes.

3. Amateur Radio Events Calendar

Stay connected with the Portuguese ham radio community through the built-in events section. Discover upcoming amateur radio activities, contests, field days, and gatherings all in one convenient location.

Important Notes

The platform emphasizes responsible amateur radio operation. Users must:

Hold proper licensing before transmitting
Identify themselves correctly on air
Comply with repeater owner guidelines
Follow frequency band plans and regulations

Open Source

Repetidores is open source software released under the GPL-3.0 license. You can view the source code, report issues, or contribute on GitHub.

Try It Out

Visit repetidores.jcalado.com to access your all-in-one amateur radio companion for Portugal. Install it as a PWA on your device for instant access to repeaters, band plans, and events wherever you are.

Whether you're a seasoned operator planning your next portable operation, a new ham learning the ropes, or an active community member looking for the next gathering, Repetidores brings together all the essential information you need in one convenient, mobile-friendly platform. Stop juggling multiple websites and bookmarks—everything you need is right here.

RT4D Codeplug Editor - A Modern, Open-Source Tool for Your Radtel RT-4D Radio

Joel Calado — Tue, 28 Oct 2025 00:00:00 GMT

RT4D Codeplug Editor: A Modern, Open-Source Tool for Your RT-4D/Retevis RT84 Radio

Source code at https://github.com/jcalado/rt4d-cps

What is RT4D Codeplug Editor?

If you own a Radtel RT-4D (analog/DMR) radio, you know that programming it with the official Chinese Programming Software (CPS) can be... challenging. That's where RT4D Codeplug Editor comes in - a modern, open-source alternative built from the ground up to make radio programming straightforward and reliable.

Why Use RT4D Editor?

🎯 Built for Accuracy

Unlike guesswork-based editors, RT4D Editor was developed through careful reverse-engineering of the official CPS. Every setting, every byte offset, every dropdown value has been verified against the official software to ensure your radio configuration is exactly what you expect.

🖥️ Clean, Modern Interface

Tabbed interface for organized access to Channels, Contacts, Zones, and Settings
Real-time editing with immediate visual feedback
Advanced settings dialog for power users who want full control
Cross-platform support - works on Windows, Linux, and macOS

📡 Complete Feature Support

Channel Management:

Supports all 1024 channels
Both analog (FM/AM/SSB) and DMR digital modes
Full CTCSS/DCS sub-tone support (all 210+ codes)
Scrambler, encryption, and privacy features
Talkaround, scan, and alarm settings

Contact & Zone Organization:

Manage up to 1000 DMR contacts
Group lists for organized contact groups
Zone-based channel organization
All Call, Group Call, and Private Call support

Radio Settings:

Identity: Radio name, DMR ID, startup messages
Audio: Separate controls for analog and DMR audio
- TX Mic Gain (0-31) and RX Speaker Volume (0-63)
- DMR Call audio with independent gain controls (0-24)
- Beep settings for various events
Display: LCD contrast, brightness, display modes
Power management and dual-watch settings
4 programmable clock/timers
Frequency lock ranges for band limiting
Scan settings (direction, dwell time, modes)
Function key programming (40 different actions)
DMR enhancements: hang times, remote control, call display
Advanced: NOAA weather channels, spectrum scan, detection range

How It Works

The editor reads and writes .4rdmf files - the binary codeplug format used by the RT-4D radio. The file structure includes:

CFG Section (4096 bytes): Radio settings, identity, audio, display
Channels (1024 × 48 bytes): All channel data
Contacts (1000 × 32 bytes): DMR contact directory
Group Lists (250 × 288 bytes): Contact groupings
Zones (250 × 512 bytes): Channel organization
Encryption Keys (256 × 40 bytes): Privacy keys

Every field has been mapped to its exact byte offset through careful analysis of the official CPS software, ensuring 100% compatibility with your radio.

Technical Details

For the technically curious:

Built With:

Python 3.x
PySide6 (Qt6) for the GUI
Binary parsing with struct module
GBK text encoding for Chinese character support
BCD encoding for DMR IDs

Key Architecture:

models.py - Data structures for all codeplug entities
parser.py - Binary file reading and conversion to Python objects
serializer.py - Python objects back to binary format
dropdowns.py - All valid values for radio settings
gui/ - Qt-based user interface

File Format Documentation: Complete documentation of the .4rdmf binary format is included in CODEPLUG_FORMAT.md, making it easy for other developers to build compatible tools.

Getting Started

Read from Radio: Use the official CPS to read your current config and save as .4rdmf
Open in RT4D Editor: Load the file and make your changes
Save: Export back to .4rdmf format
Write to Radio: Use the official CPS to write the modified file back

Settings Organization

The Advanced Settings dialog logically groups related settings:

📻 Analog Audio Settings - Squelch, mic gain, speaker volume, beeps for FM/AM/SSB operation
🔊 DMR Audio Settings - Separate controls optimized for digital voice with call-specific audio levels
🖥️ Display Settings - Screen brightness, contrast, display modes
📡 DMR Operation Settings - Remote control, hang times, call display
⚙️ Advanced Features - NOAA, spectrum scan, detection settings

Open Source & Community Driven

RT4D Codeplug Editor is open-source software, developed through reverse-engineering the official CPS to provide accurate, reliable radio programming. The project welcomes contributions, bug reports, and feature requests.

Key Benefits of Open Source:

Transparent code - see exactly what's happening with your radio data
Community improvements - bugs get fixed quickly
Cross-platform - not locked to Windows
Future-proof - won't become abandonware

What's Next?

Future enhancements on the roadmap:

DTMF programming system UI (data structure complete)
Import/export from CSV for bulk editing

Conclusion

Whether you're a ham radio operator, professional radio user, or just someone who wants reliable control over your RT-4D radio programming, RT4D Codeplug Editor offers a modern, accurate, and user-friendly alternative to the official CPS.

Github repo at https://github.com/jcalado/rt4d-cps

RT4D Codeplug Editor is not affiliated with or endorsed by the radio manufacturer. It's an independent, community-driven project created through reverse-engineering for compatibility and educational purposes.

RadShot: A Lightweight Screenshot Tool for Radtel RT-4D

Joel Calado — Sun, 18 Jan 2026 00:00:00 GMT

RadShot: A Lightweight Screenshot Tool for Radtel RT-4D

If you own a Radtel RT-4D, you've probably wanted to capture what's on that little 128x64 display at some point — maybe to document a configuration, share a channel setup, or just show off your radio's screen online.

RadShot is a small Windows utility that does exactly that. Connect your RT-4D via USB, click capture, and save the screenshot as a PNG.

What It Does

Captures the RT-4D display over serial connection
Live preview of the captured screen
Gallery view to browse multiple captures
Rename and organize your screenshots
Export to PNG with one click

Why I Built It

I wanted a simple, fast tool to grab screenshots from my RT-4D without the overhead of larger applications. The result is a single executable under 300KB that just works.

Features

The interface is straightforward:

Select your COM port from the dropdown
Click "Capture" to grab the current display
Preview appears instantly
Save to your preferred folder

You can capture multiple screenshots in a session and browse them in the gallery view before deciding which ones to keep.

Download

RadShot is free and open source. Grab it from GitHub:

github.com/jcalado/radshot

Prebuilt Windows binaries are available in the Releases section.

Technical Notes

For the curious: RadShot is written in C++ using Dear ImGui for the interface. The entire application compiles to a single portable executable with no external dependencies. It communicates with the RT-4D using the same serial protocol the radio uses for programming.

If you're an RT-4D owner, give it a try and let me know what you think. Issues and contributions are welcome on GitHub.

Remmina RDP Protocol Missing After Installing freerdp on Arch Linux

Joel Calado — Fri, 13 Mar 2026 00:00:00 GMT

Installed Remmina on Arch Linux but RDP isn't in the protocol list? Install freerdp:

sudo pacman -S freerdp

Then reboot. Restarting Remmina alone won't do it — the RDP plugin only appears after a full system reboot.

VoxLink: A Push-to-Talk Client for SvxLink Reflectors

Joel Calado — Sat, 11 Apr 2026 00:00:00 GMT

VoxLink: A Push-to-Talk Client for SvxLink Reflectors

If you use SvxLink reflectors to connect repeaters and stations, you've probably wished you could jump on from your phone — without lugging a radio or sitting at a desktop client. VoxLink is an Android app that does exactly that.

Connect to any SvxLink reflector, pick a talkgroup, and hit PTT. That's it. No accounts, no subscriptions, no setup wizards.

Why I Built It

SvxLink is a fantastic system for linking amateur radio repeaters over IP, but the options for mobile clients have always been limited. I wanted something that felt native on Android, worked reliably in the background, and didn't compromise on audio quality. So I built one.

What It Does

VoxLink speaks the SvxLink Reflector Protocol V2 natively — TCP for control and signaling, UDP for audio. It handles authentication, heartbeats, talkgroup selection, and node tracking, all while streaming Opus-encoded audio at 16 kHz.

Three PTT Modes

Hold — press and hold to transmit, classic radio style
Latch — tap to toggle TX on and off
VOX — voice-activated transmission with adjustable threshold and delay

Multiple Server Profiles

Save and switch between different reflector servers. Each profile stores its own callsign, auth key, talkgroup, and connection details. You can also import and export server configurations as JSON to share setups with other operators.

Live Node List

See who's connected to the reflector in real time. The nodes screen shows all stations on your current talkgroup with their callsigns.

Audio That Stays On

VoxLink runs as a foreground service with wake lock and WiFi lock, so it stays connected even with the screen off. Audio routing supports speaker, earpiece, and Bluetooth. There's also a time-out timer (configurable from 30 seconds to 10 minutes) with a vibration warning before it cuts your transmission.

Recording

Optionally record TX and RX audio as WAV files, organized by talkgroup and timestamp. Play them back or share them directly from the app.

Under the Hood

VoxLink is built with Flutter and uses native platform channels for low-latency audio I/O on Android. The Opus codec runs via FFI bindings to the native C library, and a custom FIR polyphase resampler handles the 48 kHz to 16 kHz conversion using SvxLink-compatible filter coefficients. An adaptive jitter buffer with packet loss concealment keeps audio smooth even on spotty connections.

State management uses Riverpod, and the UI follows Material 3 with dynamic color support.

Get It

VoxLink is free — no ads, no in-app purchases, no subscriptions.

Available on the Google Play Store. More details at voxlink.jcalado.com.

If you're a ham using SvxLink reflectors, give VoxLink a try. Feedback and bug reports are welcome.

Ulanzi Stream Controller D200 as a Bitfocus Companion surface

Joel Calado — Mon, 20 Apr 2026 00:00:00 GMT

Bitfocus Companion's new surface plugin system (shipped in 4.3.0) makes it possible to add support for new control surfaces without touching Companion itself. I used that to plug in the Ulanzi Stream Controller D200, a 13-button, 5×3 grid Stream-Deck-alike that's cheaper than the Elgato but wasn't supported out of the box.

Project: github.com/jcalado/companion-surface-d200

What it does

13 Companion-controlled buttons, each with a 196×196 icon
Brightness, button events, press/release
Small-window status display (clock / system stats), selectable per surface
Drop-in installable as a developer module in Companion 4.3.0+

The reverse-engineering rabbit hole

redphx/strmdck had the wire protocol in Python: 1024-byte HID packets framed as 0x7c 0x7c [cmd:u16] [length:u32] [data...], with full button uploads pushed as ZIP archives containing a JSON manifest plus per-button PNGs. That gave me a head start, but a few things were out of date or wrong:

strmdck targets VID/PID 2207:0019. On my Linux box, the D200 enumerated as 18d1:d002, Google's ADB-style VID/PID. Standard USB control transfers to it failed with EPROTO, adb devices hit the same wall.
My first port used node-hid, which couldn't see the device at all. Switching to node-usb and bulk transfers got further but still failed with LIBUSB_TRANSFER_ERROR.

A USBPcap capture of Ulanzi Studio on Windows cleared everything up: the D200 actually exposes two USB devices simultaneously through an internal hub. The 18d1:d002 one is an abandoned/bootloader interface, dead on arrival from the host's point of view. The real device is 2207:0019, a proper HID composite with two interrupt endpoints at wMaxPacketSize = 1024 plus a keyboard interface for the standalone hotkey buttons.

Windows enumerates both cleanly. Linux, connected directly, gives up after three tries:

usb 3-1: can't read configurations, error -22
usb 3-1: can't read configurations, error -22
usb usb3-port1: attempt power cycle
usb 3-1: New USB device found, idVendor=18d1, idProduct=d002

Only the useless one survives. The fix turned out to be stupidly simple: a USB 2.0 hub between the D200 and the host. With the extra hub layer, both child devices enumerate, usbhid binds to the HID interface, and node-hid just works.

That one detail burned a couple hours.

The ZIP manifest was wrong in strmdck too

The captured ZIPs from Ulanzi Studio use:

manifest.json
Images/<uuid>.png

(flat, no page/ prefix) and require a per-button Font object inside each ViewParam[0]. Getting icons to render required matching that structure exactly, including declaring the small-window slot 3_2 (which spans two cells) with SmallViewMode: 1.

Plus a lovely firmware bug: the byte at file offsets 1016 + 1024·N in the ZIP payload must not be 0x00 or 0x7c, or the upload is silently corrupted. strmdck's workaround (retry compression with a random-length dummy file appended) ports over directly.

Writeup

The full wire protocol and ZIP format are documented in PROTOCOL.md; Linux-specific setup (hub requirement, udev rule, the diagnosis of the enumeration failure) is in SETUP.md.

Support

If this is useful to you: ko-fi.com/jcalado.

CGTimer 3.0

Joel Calado — Wed, 29 Apr 2026 00:00:00 GMT

CGTimer 3.0 is out. It's a major release that rebuilds the app around a flexible layout system and adds first-class support for the production tools I keep reaching for: OSC control surfaces and Blackmagic HyperDeck recorders.

Download: github.com/jcalado/cgtimer/releases/tag/v3.0.0

A layout system that gets out of the way

The biggest change is that the dashboard is no longer a fixed arrangement. You can split panels horizontally or vertically, drag widgets between slots, and pull new widgets in from a palette. Resize anything by dragging the dividers, and reconfigure widgets (label, colors, options) inline. Press F at any time to go fullscreen.

If you used the old version, the default layout still stacks a remaining timer over an elapsed timer, so first-run still feels familiar.

New widgets

Time-of-day countdown, replacing the older production clock. Pick a wall-clock time and the widget counts down to it.
Timezone clocks for any city or zone, with themed previews so you can see what they'll look like before adding them to a layout.
HyperDeck status, showing live timecode and recording state from a connected Blackmagic HyperDeck.
A unified renderer for the remaining, elapsed, and loop timers so they all share the same typography.
The loop icon now spins while a loop is active, so it's easy to tell at a glance.

All clocks are now driven from a single wall-clock-aligned tick, so widgets on the same screen no longer drift apart by a fraction of a second.

OSC and HyperDeck

CGTimer now ships an OSC server, so an external console can drive timer commands (start, stop, reset, and so on) and switch between layouts remotely. That last part is the one I wanted most: building a production layout once and switching to it from a button on a Companion or QLab surface.

HyperDeck support is end-to-end: configure recorders from the new Recorders tab in preferences, monitor their status, and drop a HyperDeck widget into your layout to see the deck's timecode next to your timers.

Preferences, rewritten

The Forge-generated preferences window is gone. In its place is a custom Fluent UI window with five tabs: Application, Colors, Timezones, Recorders, and Server. Open it with Cmd/Ctrl + ,. Toggles in the Production tab are now inline, the Colors tab has been reformatted, and the Timezones tab has a themed time preview so you can pick zones without guessing.

Multi-display

Display matching is now hardened against monitor IDs changing across reboots, so windows return to the right screen instead of jumping around. Fullscreen and window positioning behave correctly when you plug or unplug displays mid-session.

Builds

3.0 ships builds for everything I can produce on CI:

macOS arm64 (.dmg, .zip)
Windows (Setup.exe installer and a new portable .exe)
Linux (.AppImage, .deb)

Auto-update metadata is published alongside the artifacts on all three platforms.

Under the hood

If you fork the project, the toolchain is now Vite plus electron-builder, replacing the previous Webpack and Electron Forge setup. Builds are noticeably faster and the config surface is much smaller. Electron, React, and Fluent UI are all on their latest majors (41, 19, and v9 respectively).

Issues, ideas, and PRs welcome at github.com/jcalado/cgtimer.

VoxLink 1.2: Audio file playback, deep links, smarter audio routing

Joel Calado — Thu, 30 Apr 2026 00:00:00 GMT

VoxLink 1.2: Audio file playback, deep links, smarter audio routing

VoxLink 1.2 is out. The headline feature is audio file playback — you can now transmit a pre-recorded clip over the air directly from the PTT screen — and it brings a stack of smaller workflow improvements on top.

Audio file playback

A new file-playback button sits next to PTT. Tap it, pick an audio file, and VoxLink streams it over the air while a progress card tracks playback. Local monitoring plays the same audio out the speaker while you transmit, so you actually hear what's going out.

A few sensible guard rails:

Disabled while VOX mode is active — file playback and voice-activated TX don't mix.
Disabled while another station is talking — no stomping on a live conversation.

It's the feature I've wanted for ages for tests, recorded ID announcements, and net openings.

Faster talkgroup workflows

Managing presets used to mean diving into the server edit form. Several changes make presets feel first-class:

Talkgroups entry in the active server's menu — jump straight to preset management without re-opening the edit form.
Optional onboarding right after you add a new server, so you can set presets up while it's fresh.
‹ / › chevron buttons on the PTT screen to step through presets without leaving the talk view (appears when the server has two or more).
Monitor another TG… in the picker — drop into any arbitrary talkgroup for monitoring without first turning it into a preset.
Per-preset "Monitor by default" flag in the talkgroup presets screen — pin specific talkgroups to always be monitored when you connect.

voxlink:// deep links and QR codes

You can now share server configurations as a single URL or QR code. The format:

voxlink://host:port/?name=&user=&pass=&tg=

Open one (or scan a QR code that encodes one) and VoxLink launches with the new-server form prefilled — no manual copying of host, user, or talkgroup numbers. Useful for net coordinators, club groups, or just sharing your own setup across devices.

Live audio routing

Two changes that fix a long-standing pain point:

The audio output picker in Settings is now live — it lists the actual devices currently available (built-in speaker, wired headset, paired Bluetooth device, etc.) instead of a fixed enum that didn't always match reality.
Auto-rerouting — when Audio output is set to Auto, plugging in or removing a headset or Bluetooth device switches the route on the fly. If your selected device disappears mid-session, a toast tells you what happened.

The Settings rows for audio output and audio input also stack the device or source name below the label, so a long Bluetooth name no longer wraps awkwardly.

Smaller changes

The PTT screen header now shows the server name (with host as fallback) instead of the raw hostname — friendlier when you're managing multiple reflectors.

Fixes

Snackbars on the Servers and Recordings screens now auto-dismiss when an Android accessibility service is active. Previously they could sit on screen indefinitely, and recordings deleted via the snackbar were never actually cleaned from disk.
The "Connection timed out" warning no longer lingers on the PTT screen after a successful auto-reconnect.
The reflector connection no longer reconnects in a loop after a protocol-level error like Access denied.

Get it

VoxLink 1.2 is rolling out on the Google Play Store. More details at voxlink.jcalado.com.

If you hit a bug or have an idea, drop into the VoxLink Telegram community. 73.

VoxLink 1.3: APRS, accessibility, and a settings overhaul

Joel Calado — Tue, 12 May 2026 00:00:00 GMT

import KofiBanner from '~/components/KofiBanner.astro'

VoxLink 1.3: APRS, accessibility, and a settings overhaul

VoxLink 1.3 is out. The headline is APRS — VoxLink now speaks APRS-IS, with a live map, station list, messaging, and configurable beaconing — but a lot has happened around it: a full set of accessibility features, a reorganized settings area, Bluetooth audio routing fixes, and on-screen alerts for monitored talkgroup activity.

APRS

VoxLink is now an APRS client. Connect to APRS-IS with your callsign and passcode and you get:

A live map (OpenStreetMap) with stations as markers, callsigns labeled under each symbol, and common APRS symbols mapped to Material icons.
A stations list with a search box, sort by distance / last-heard / callsign, last-heard age pills, an inline movement chip for moving stations, category filter chips with a stale-fade, pull-to-refresh, dense rows, and persisted sort. Tapping a station opens a detail sheet with path, status, course/speed/altitude, and other metadata.
Messaging — send and receive APRS messages directly from the app.
Beaconing with two positioning modes: automatic from GPS (with tunable accuracy) or a manual map picker for fixed locations. Each mode has its own settings, and a smart-beacon fallback derives speed from distance/time when the GPS speed channel is unreliable.
Background operation — the APRS-IS connection (and position stream) is kept alive through the foreground service, so beacons keep going out and incoming traffic keeps flowing when the app isn't in front.
Parsing for compressed positions, Mic-E, course/speed/altitude, objects, and items.
VoxLink now identifies itself with the officially-assigned APVOXL tocall on the APRS-IS network.

The whole feature lives behind a master toggle in Settings, so if you don't want it, it's not in your way. UI is localized in English and Portuguese.

Accessibility

VoxLink 1.3 ships a dedicated accessibility section with options that make the app usable in tougher conditions:

Outdoors mode — a larger PTT button with a glanceable outer ring you can hit without looking.
Huge talker display — 56px callsign, 22px subtitle, for reading at a glance.
Green screen flash on RX talker start, so you know someone's transmitting without looking at the indicator.
Reduce motion — disables the pulsing connection indicator and other ambient animation.
Haptic strength — Off / Subtle / Strong, scaling all vibration durations across the app.
TX start/stop vibration cues — a short pulse on TX start, a double-tap on stop.
High-contrast state colors on the PTT button and talker display.

Monitor activity alerts

Monitored talkgroups now surface activity directly in the app:

A monitor activity banner appears at the top of the PTT screen when a monitored TG goes active. Tap it to switch to that talkgroup.
OS notifications for talker activity on monitored TGs and for connection drops, with toggles to enable or disable each in the new Notifications section.
A 5-second idle-coalesce window keeps the banner stable through bursts of short transmissions.

Settings, reorganized

The Settings screen had grown into a long scroll. It's now split into focused sub-screens, all reachable from a clean grouped-card index:

Transmission (PTT / VOX / TOT)
Audio
External PTT
Notifications
PTT screen controls
Accessibility
Connection
APRS

Each row uses a right-chevron for navigation. Less hunting, more findability.

Other small additions: a Keep screen on toggle (wired to wakelock), an APRS server picker, and a server export/import flow that uses your share sheet (with a visible warning about the secrets it contains).

Audio

Bluetooth audio routing fix — the comm-device session lifecycle is now handled properly, which resolves a long-standing class of routing issues with BT headsets. A live audio output picker enumerates devices in real time, auto-reroutes on connect/disconnect when set to Auto, and surfaces a fallback toast when a chosen device disappears.
User-selectable BT audio mode — pick whether the Bluetooth path uses the voice-call (SCO) profile or the media profile, depending on what your headset does well.
48 kHz Opus — the encoder and decoder now run at 48 kHz, improving audio quality.
RX hardening for background and locked-screen wake-ups, including keeping the RX path warm across QSOs and surviving fast keyup → keydown patterns without missing the start of the next over.
Android 16 WiFi PSM mitigation — the app holds a multicast lock and runs a 1 Hz UDP heartbeat so the radio doesn't park itself in power-save mode while backgrounded.
AudioTrack lifecycle work: recreated after long idle to avoid the stuck-slow-mixer bug, jitter-buffer tail drained on talkerStop to stop clipped overs, zombie playback timers prevented from double-draining, decoder + jitter buffer reset on foreground resume, audio channel taken off the main thread, FAST-mixer hint dropped.
Several stability fixes around mic leaks in VOX, decoder teardown, and AudioTrack underruns.

Playback improvements

The audio file playback feature from 1.2 grew up:

Playlist-based playback with a strip UI for the active entry.
Pause / resume that preserves the absolute file offset.
Manual-PTT interrupt — keying up cleanly stops the file.

Nodes & talkgroups

The Nodes screen now splits the list by activity on the selected talkgroup, so you can tell who's actually using the channel right now.
Scan across talkgroups.
Per-preset default monitored TGs and arbitrary-TG monitoring.
Chevron buttons to step through presets on the PTT screen.

Other fixes & polish

Recordings: swipe-to-delete with a working Undo.
Servers: first server is auto-activated on add and on load, so the PTT picker always has presets to show.
Polished active-server hero card and servers dashboard.
Manage talkgroups directly from the active server menu, and onboard them when adding a new server.
RX is now torn down cleanly on talkgroup switch, and monitor/scan toggles are persisted across restarts.
voxlink:// deep links continue to work for provisioning servers via URL or QR.
A grab bag of smaller stability and translation fixes.

1.3.1

A short follow-up patch shipped on top of 1.3.0 with a few requested PTT-screen options and one more reliability fix:

Optional TX / TOT timer row on the PTT screen.
Optional Quit item in the PTT-screen connection menu, for when you want to fully stop the app instead of backgrounding it.
Foreground service notification now reflects RX state (and the mediaPlayback FGS type was dropped now that audio routing is handled directly).

Get it

VoxLink 1.3 is rolling out on the Google Play Store. More details at voxlink.jcalado.com.

If you hit a bug or have an idea, drop into the VoxLink Telegram community. 73.