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Powersoff Signal Heat-map

powersoff.com · 10×10 m grid · Wi‑Fi, Bluetooth & motion · Installable PWA

Online

JavaScript is required. The Powersoff Signal Heat-map runs entirely in your browser and needs JavaScript enabled to read sensors and draw the map. No data leaves your device.

1 How are you measuring?

Solo device
One phone/tablet; tap the map to set your position Multi-device
Several devices at fixed positions (triangle, square, 3D)

Scan speed Use solo position on map Show dead zones Dead zone window s

Formation This device is slot (0 = here) Phase duration min Warn before switch s

2 Start collecting signals

Motion time windows: 5 s 30 s 300 s

3 Devices & sources

Click + to add phones, desktop helpers, Bluetooth headphones/mics, smart watches, and other devices. Each maps to a position on the heatmap.

Advanced

Manual input — fallback when sensors unavailable

Add data points manually when sensors or APIs are unavailable. Position (x, y) in meters on the 10×10 grid.

X Y Signal (dBm) Type

Geo fallback (when geolocation unavailable): Lat Lng

Optional: Desktop helper (Windows) — for richer WiFi scan data

HTTPS: The desktop helper uses ws://127.0.0.1:8732 and is blocked from this page. Use the in-browser Wi‑Fi monitor here, or run a local copy of this file with wifi_helper.exe.

Helper source and build scripts are served at /helper/ on this deployment. Download bundles all files for offline build.

cl /nologo /O2 wifi_helper.c ws2_32.lib advapi32.lib /Fe:wifi_helper.exe
wifi_helper.exe

Device matrix (custom positions)

Add devices and set (x, y, z) in meters. Used when Formation = Custom.

Pattern editor (motion colors)

Debug log

Settings

Remember formation & pattern settings on this device

On production HTTPS (powersoff.com, Cloudflare Pages, etc.), settings are session-only until you enable this. Sensor data is never stored on disk.

Change log

v3.3 — Newtonian gravity: sensor-origin body models (L×W×H, mass), accessor detection in field-of-relevance adjacency, g = GM/r² superposition to objects and g₀ ground; perspective overlay.
v3.2 — Power metrology: battery/plug sampling, localized drain dL/dt, P_m vs distance/velocity; isolated green session heatmap; toolbar icon (grid·clock·bolt·plug).
v3.1 — Cloudflare Pages deploy package: deploy/ output, /helper/ assets linked, hybrid local+HTTPS docs.
v3.0 — Sensor channel layers: Wi‑Fi / BT / motion with distinct colors and textures for u, |du/dt|, |d²u/dt²| on the grid.
v2.9 — Terminology: coverage deficit metric (MCDM) — complementary support deficit with context weight field w(r); calculus/metrology naming throughout.
v2.8 — Context weight w(r) from spatial anchoring deficit, magnitude derivative |du/dt|, position derivative |dr/dt|, inter-track |dd/dt|.
v2.7 — Complementary void measure on spatiotemporal sample support; deficit index I vs observed sum Σ.
v2.6 — + Device registry: add mobile, desktop helper (multi-port, download build files), Bluetooth headphones L/R, microphone, smart watch, IoT; per-device position, slot, pair/connect.
v2.5 — Full single-file capability: 32×32 grid heat renderer with textures (7), static/dynamic patterns, time-slice aggregation, height shading, view modes (grid / points / combined). Canvas-only; zero external JS.
v2.4 — (merged into v2.5) Canvas visual engine port.
v2.3 — Deploy path config (deployPath, auto-detect on powersoff.com), session-only prefs on production (opt-in remember), dead-zone style variants, Advanced panel, HTTPS helper note, Apache .htaccess.
v2.2 — Deployment hardening: high‑DPI canvas fix (sharp on mobile/retina), canonical + PWA head metadata, no‑JS fallback, version/privacy text synced.
v2.1 — Installable PWA: inline manifest, blob service worker (offline), Canvas icons (192/512 + maskable), install button, update banner, online/offline indicator, HTTPS host detection for powersoff.com.
v2.0 — Powersoff branding; All Rights Reserved license.
v1.1 — Manual input (Wi‑Fi, BT, motion), geo fallback, safe storage fallback.

Privacy & Legal

Privacy Notice

This tool runs entirely in your browser. Sensor readings (Wi‑Fi, Bluetooth, motion) are held in volatile memory only and are cleared when you press Reset or close the page. They are never transmitted to any server.

The only optional data written to disk is your interface preferences (formation, pattern colors, device matrix) when you enable Remember formation & pattern settings in Settings. On powersoff.com this is off by default; preferences stay in memory for the session only.

Permissions

You will be prompted by your browser before granting access to Bluetooth devices, motion sensors, geolocation or other optional APIs. Granting permission is voluntary and can be revoked at any time.

Terms of Use

By using this page you agree to operate it only on devices and networks you own or have explicit permission to test. You are solely responsible for complying with local laws regarding radio scanning and data collection.

License

Copyright © Lawrence Allen Bowker. All Rights Reserved. No part of this software may be copied, modified, distributed, or used without express written permission from the rights holder.

Disclaimer

The software is provided “as is” without warranty of any kind. The authors are not liable for any damages arising from its use.