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Build Log

Offline Trails and a Radio That Hears the Sky

· 3 min read

Godwit can take you to the trail now, not just the town. Load your GPX tracks from a USB stick or record your own as you drive, and the head unit guides you to the closest point of the trail. Plug in one small radio stick and it also picks up FM, weather radio, and the planes and ships around you. None of it needs a signal.

Your trails, on the dash

A GPX file is how trail apps and handheld GPS units save a route. Copy yours onto a USB stick, plug it in, and Godwit keeps a library of them. Give each one a name and a color, see how long it is and how much it climbs, and switch it on to see it drawn on the map under your route.

Pick a trail and ask for directions, and Godwit plans a route to the closest point of it. That is the part a road map never helps with: finding where the dirt starts.

Press record on the map and it saves your own track as you drive, even across a power cut.

The maps underneath are the same offline maps Headwaters carries for the rest of the rig. If you have used trails in Overlook, the idea will feel familiar: streets to the trailhead, trails from there, now up on the dash.

One radio stick, four radios

An RTL-SDR is a USB radio receiver a little bigger than a thumb drive. Godwit turns one into four apps:

  • FM radio with station names. The first scan fills your presets for you.
  • Weather radio, naming the nearest transmitter on each channel.
  • Aircraft overhead, as a list or a radar-style scope you zoom with the left knob.
  • Ships nearby, for the coast and the big lakes. This one has not met a real ship yet.

The four take turns with the one stick. Aircraft, ships and weather radio are for the United States for now. Which antenna works best, and why there is no AM radio yet, are both in the video.

The stick in the video is the Nooelec NESDR SMArt v5 kit. That is an Amazon affiliate link. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you.

Things you will notice

The second knob is in, and climate, radio and the map now put both of them to work.

Spin a knob fast and it no longer jumps backwards. The video shows the fix, and whether a generic knob from a parts bin would do the job.

Answering texts by voice got smarter, down to reading phone numbers back one digit at a time.

The streaming service apps are gone. Music comes from your phone over Bluetooth, or from your own library on a USB stick.

What happens on the head unit stays there

Godwit's everyday logs record what happened and leave out what was said, what your messages say, and which phone was connected. More detail is written only when you switch it on to chase down a problem, and switching it off wipes it. And Erase Everything in Settings clears everything personal, from paired phones to your trails, while keeping the maps.

Your questions, in the video

The last part of the video answers what you asked after episode two: push to talk, Jellyfin or Plex, steering wheel controls, hooking up a real amplifier and speakers, and Meshtastic. It ends with a hint of something coming for these knobs.

Godwit is demonstration and test software. It runs on the bench and is still under development. Do not install it in a vehicle you drive.

Follow along

The Godwit source is free and MIT licensed, like the rest of TrailCurrent, and the Godwit page still lets you drive it in your browser. The knobs are Elecrow 1.28 inch rotary displays, and Elecrow sent the second one for this build at no cost. That link carries our affiliate tag. It costs you nothing extra and sends a small cut back to the project.

New episodes go up on the open source channel. What should Godwit pick up next? Tell us in the video comments.