Documentation Index
Fetch the complete documentation index at: https://docs.altnautica.com/llms.txt
Use this file to discover all available pages before exploring further.
Power and Runtime
The ADOS Ground Agent is designed to stay compact. It does not need an internal battery to work in the field. Power it from USB-C using a wall adapter, a USB-C PD power bank, a vehicle adapter, or another regulated field power source.
This keeps the ground node small and lets you choose the runtime you need for each job.
Recommended power sources
| Source | Use it for | Notes |
|---|
| USB-C wall adapter | Bench work, lab testing, fixed setup | Use a supply that can sustain the board’s required output under load. |
| USB-C PD power bank | Field operation | Best portable option. Pick a bank with sustained output, not only a high peak rating. |
| Vehicle or field battery adapter | Long sessions | Use only regulated USB-C output. Avoid bare battery leads into the board. |
| Laptop USB-C power | Short setup only | Some laptops limit current. Use separate power when video, WiFi AP, HDMI, or extra radios are active. |
Do not judge power banks only by the mAh label. Most banks print mAh at internal cell voltage, not at USB output. Runtime should be estimated in watt-hours.
Expected draw
Use these bands for planning:
| Ground Agent mode | Expected draw | Plan for |
|---|
| Direct/headless node | ~7.5 W | One radio, no HDMI kiosk, normal local clients |
| Kiosk or dual-radio node | ~9-11 W | HDMI, browser kiosk, extra radio, or heavier uplink use |
| Supply ceiling | 15 W | Power-supply sizing and brownout margin, not normal runtime |
Runtime estimates
These estimates assume 75-85% usable energy after USB conversion losses.
| Power bank label | Usable energy | ~7.5 W direct/headless | ~10 W kiosk/dual-radio | 15 W ceiling |
|---|
| 10,000 mAh | ~28-31 Wh | ~3.7-4.1 h | ~2.8-3.1 h | ~1.9-2.1 h |
| 20,000 mAh | ~56-63 Wh | ~7.5-8.4 h | ~5.6-6.3 h | ~3.7-4.2 h |
| 30,000 mAh | ~83-94 Wh | ~11.1-12.5 h | ~8.3-9.4 h | ~5.5-6.3 h |
| 99 Wh PD bank | ~74-84 Wh | ~9.9-11.2 h | ~7.4-8.4 h | ~5.0-5.6 h |
USB tether power
USB tether is a data path first. A laptop may also power the Ground Agent, but that is not the recommended field setup.
For reliable USB tether:
- Power the Ground Agent from a wall adapter or USB-C power bank.
- Use a separate USB-C cable that is explicitly data-capable.
- Treat laptop back-power as a short setup convenience only.
- If video freezes or the USB network drops under load, test again with a known-good power source before changing radio settings.
Brownout symptoms
Power problems often look like radio or network problems:
| Symptom | Likely cause | First fix |
|---|
| USB tether appears and disappears | Host power limit or bad cable | Use separate power and a known data cable |
| Video freezes when more clients join | Supply sag under WiFi load | Use a stronger USB-C source |
| Radio adapter disappears from diagnostics | Brownout on the USB bus | Change power source and cable |
| HDMI kiosk works, then drops video | Load spike from display and browser | Use a higher-output USB-C source |
| Works on wall power but not on a power bank | Bank cannot sustain output | Use a PD bank with sustained output rating |
Field checklist
- Use a USB-C source that can sustain the required output.
- Carry one known-good data cable and one known-good power cable.
- Keep the power bank out of direct sun when possible.
- Start long sessions with the bank fully charged.
- For USB tether, separate power from data whenever the hardware allows it.
What is next
