Scanner Follow: The Map Shows Who Your Scanner Is Hearing

Scanner Follow joins your scanner to the UKAFG interactive map. Each time the scanner stops on an ATC frequency, the map lights up the airspace that frequency works and shows only the aircraft inside it, at the right levels — so the voices you’re hearing come from a short list of aircraft you can see, rather than everything in the sky. It works with every Squawker Connect scanner type, hardware or SDR, and with the Fast Scanner.

You need access to the interactive map, which the Squawker PC subscription includes (see Interactive Map Access).

Switching It On

• Any Connect profile — the 🗺 Follow on map toggle beside the Frequency box on the Connect tab.
• Fast Scanner — the Map switch at the right-hand end of the Now-Listening panel. It’s the same setting as the toggle above, for that profile.

Switching it on opens the map window inside Squawker PC (or uses the one already open) and a bar appears along the bottom of the map: Following the scanner (profile name) – waiting for a stop. The toggle is remembered per profile, but only when you move it yourself — closing the window doesn’t save it off. If you reopen a profile with Follow remembered on, open the map (the Map button on the main window’s General panel) and the stops reach it from there; the toggle’s tooltip says so until you do.

For a hardware scanner, every frequency the radio reports is a stop. For the Fast Scanner it’s the live park — the map follows the moment the squelch opens, and is told when the scanner resumes.

What a Stop Shows

Say the scanner stops on 124.600. The bar reads something like 124.600 · London Control · Daventry South S32 · FL255–UNL · 11 aircraft. The Daventry South volumes are drawn with a bright outline and light fill, the map fits to them (the first time, and only if they aren’t already in view), and every aircraft outside the volume or outside its level band disappears. Stop on 118.700 instead and it’s the Heathrow ATZ, aircraft on the ground and in the circuit.

What’s drawn depends on what the frequency is:

• Area sectors (London, Scottish, Terminal Control) — every polygon with that name, each with its own flight-level band. A sector can be a dozen separate volumes.
• Western Radar — its own area, FL195 and above.
• Approach, Director, Radar, Arrival, Departure — the aerodrome’s CTR, CTAs and TMA from the surface to their top; a 25 nm circle to FL150 where there are none.
• Tower, Ground, Delivery, Air/Ground, AFIS — the ATZ (or a 2.5 nm circle), ground level up to just above its top. Aircraft on the ground show only for tower frequencies.
• LARS — a circle of the published radius around the unit, surface to FL100.
• MATZ / Zone — the military zone, surface to 3,000 ft above the airfield.
• UHF military sectors — Swanwick Mil’s sectors, from 3,000 ft up with no upper limit.

A stop on a frequency the map has no airspace for — an ATIS, VOLMET, a company frequency, 121.500, anything HF, marine or PMR — says so in the bar and leaves the previous volume up, dimmed.

When one frequency is known to be working several sectors together (bandboxed), the extra sectors come in by themselves, marked (bandboxed). If five or more aircraft in view report a QNH, the bar shows it and altitudes are corrected against aerodrome limits that are set in feet.

When the Scanner Moves On

The last volume stays up until the next stop, so you have time to pick the aircraft out; the bar notes scanning again, last stop kept. The after control on the bar can clear it instead, 15, 30 or 60 seconds after the scanner resumes.

The Bar’s Controls

• ± level slack (0 to 3,000 ft) — aircraft this far above or below the band still show.
• pad (0 to 10 nm) — aircraft this far outside the edge still show.
• Dim others — fade the aircraft outside the volume instead of hiding them.
• after — keep the last volume, or clear it 15/30/60 s after the scanner resumes.
• Widen / Narrow (sector stops only) — add the neighbouring sectors of the same group, drawn dashed, for a night when one frequency is working them all.
• Exit — leave the mode and show every aircraft again. This also switches the toggle off in the app, as does closing the map window.

Your slack, pad, dim, widen and after settings are remembered in the map.

While following, the map’s own altitude chips and height control are set aside so they can’t hide the aircraft you want; they come back on Exit.

Shared Frequencies

One channel can belong to several aerodromes far apart. Squawker Connect already picks the nearest match for a stop, and the map is told which airport and service that was, so the right volume is drawn. Where a frequency is shared between two aerodromes within range, correct the pick in the Connect window’s Live Scan list and the map follows.

The Same Mode on the Website

You can drive the mode by hand without Squawker PC: type a frequency into the map’s search box and the first row offers Focus the map on 124.600: its airspace and the aircraft in it. A map link ending in ?focus=124.600 does the same on opening.