Site status

Under active construction — and yes, the paint is still tacky.

Repeater Planner is built, coded, and maintained entirely by me as a solo project. It runs well enough that folks are already plotting real incidents, which is awesome to see—and slightly nerve-racking when I’m the only one answering the inbox when someone’s handheld doesn't match the shade on the map.

Why I Built This

Solid mapping software already exists. Heavy hitters like Radio Mobile Online and CloudRF have earned their stripes over decades, and this isn't meant to run them out of business.

It started with a practical question: what if an RF planner actually worked the way comms work in the field?

Most commercial tools are engineered for RF broadcast engineers. Before you can drop a single pin, you're hit with 30 confusing drop-downs, antenna geometry menus, and settings that assume you’re building a commercial cell tower. In real-world incident management, you don't have time for that. You’re working with standard cache gear, shifting frequencies, sketchy connectivity, and tight operational deadlines.

I wanted a clean, fast tool where you pick the actual hardware you have in your hands—like an NFES 4312 command repeater, a 4248 logistics hub, or a standard belt-worn handheld—and let the software automatically dial in the exact mast heights, gains, feedline losses, and multi-band parameters without you having to convert decibels in your head.

Because I'm developing this in the open during my off-hours, the platform is alive. Math gets refined, clutter engines get tuned, and buttons will occasionally move. If you get comfortable with a corner of the UI today, don't be shocked if it looks slightly different next month.

Why Is It Slower Than Commercial Tools?

The short answer: CPU power costs real money, and I pay 100% out of my own pocket so this stays free for everyone.

Commercial platforms run on dedicated cloud clusters backed by venture funding or hefty monthly subscription fees. This site runs on a single, self-funded virtual server.

When you request an area coverage map, the server isn't drawing a cartoon radius ring; it is crunching thousands of terrain and land-cover points across raw elevation tiles. Typical times for a planning-radius ITM run when the queue is clear:

Standard — about 1–2 minutes.
High — about 2–4 minutes.
Maximum — about 4–6 minutes. Closer to 10 minutes the first time that area has to download the 10 m elevation tiles.
Plus Ultra! — usually 20–40 minutes. Still the long one, not an overnight job.

The faster diffraction engine is quicker than those ITM numbers. A bigger radius or a busy queue adds time. You don't have to keep your browser tab open—jobs keep processing on the server even if you close the page, and longer runs will email you a Google Earth KMZ when they finish. Thank you for being patient with a one-person budget.

The RF Engine (No Painted Circles)

A modest server doesn't mean cut corners on propagation physics. Every coverage map, site-to-site backhaul, point check, and route corridor calculates a true point-to-point link budget across real elevation and land-cover models to measure whether your receiver has an honest safety margin.

The Dual Terrain Engines

Longley-Rice (ITM v1.2.2): The gold-standard Irregular Terrain Model trusted across public-safety engineering. Coverage maps default to this higher-accuracy model using a persistent background engine that calculates true per-cell path loss, matching closely with classic Radio Mobile outputs.
Deygout: A faster, multi-edge diffraction model designed for rapid sketches, briefing maps, and quick cross-ridge sanity checks without bogging down the queue.
Site-to-site backhaul always runs Longley-Rice end-to-end.

Real Hardware & Link Budgets

Instead of guessing generic numbers, the system models standard field packages out of the box:

Per-Band RF Chains: VHF command repeaters and UHF logistics links are treated as separate physical installs—distinct masts, separate feedlines, and independent frequency-scaled cable attenuation.
Antennas & Feedlines: Pre-tuned to field specs (such as 4.5 m masts, omni and Yagi patterns, and calibrated coax line loss so VHF lands right at ~3 dB).
Ground Clutter (NLCD): Where USGS Land Cover tiles exist, evergreen timber (~23 m), chaparral/scrub (~4 m), and urban canopy are raised directly onto the elevation model, plus residual foliage attenuation. The math doesn't pretend the mountains are a pool table.
Receiver Profiles: Signals are tested against realistic receiving setups—from a belt-worn handheld at 2 meters with negative body loss up to mobile rigs, base stations, and aircraft.

How to Read the Colors

Coverage maps display available fade margin (received signal minus receiver sensitivity):

Green (10+ dB margin): The comfortable cushion planners like to see on paper.
Yellow / Amber (0–10 dB margin): Above receiver threshold, but riding the hairy edge. Usable, but one dense stand of wet timber away from scratchy audio.
Purple (Below threshold): Signal shadows and dead zones. Kept visible by default so you know exactly where terrain cuts you off, but toggleable if you prefer a clean map.

What the Different Tools Do

Coverage Maps: Predicts where a specific radio setup can actually hear a site across 30-meter SRTM terrain (Standard/High) or high-density 10-meter USGS 3DEP terrain (Maximum/Ultra). You can swipe-compare two runs side-by-side or merge loaded sites into a unified "best-of" incident coverage map.
Site-to-Site Backhaul: Evaluates two-way repeater links with full Fresnel zone clearance, knife-edge diffraction, and atmospheric bending. It always reports the worst-case direction (A→B vs. B→A), because a repeater link that only talks one way is just an operational headache waiting to happen.
Point Checks: Need an instant check on a spike camp, staging area, or helibase without waiting on a full coverage map? Drop a pin to pull a fast, one-way link budget slice in seconds. Near the pin, the engine pulls fine-scale 1-meter lidar data (where available) and predicts local building diffraction and structural shadow loss (using the Global Building Atlas) so you can see if a rig parked behind a metal warehouse is getting blocked.
Route Analysis: Paints a continuous 200-foot coverage ribbon along roads or travel routes to reveal dead stretches for mobile convoys.

Reality Checks & Field Truth

Treat every result here as an educated planning estimate, not gospel.

Computer models run on math, not magic. The software doesn't know if a handheld has a bent stubby antenna, if someone is standing inside a metal garage, or if rain-soaked timber is eating 6 dB of signal that the dry satellite pass didn't account for.

Major mountain shadows and clear line-of-sight peaks will line up closely with what you see in the field and on high-dollar software. But right along the fringe, nature always gets a vote.

When it matters: walk it, drive it, or key a mic where the mouse clicked. The computer doesn't have to explain dead air to anyone; you do.

Feedback & Ground Truth

Found a bug, have a suggestion, or noticed a ridge where the radio worked fine but the map painted purple?

Drop me a line at repeater@fireguy.net. Real-world ground truth from folks carrying radios in the dirt is the only way a solo project like this gets sharper.