Frequently Asked Questions

Download the free app from Google Play. It runs on Android and gives you the FORSYTE Map and Drone ID Detection straight away, with no extra hardware.

To go further you connect a compatible radio receiver (SDR), and FORSYTE does full spectrum sensing, interference detection and multi-target scanning on it. If that is where you are heading, talk to us and we will work out what fits.

What FORSYTE can do is driven mostly by the receiver you connect to it.

An affordable RTL-SDR receiver is a good place to learn, train, and watch a smaller set of selected frequencies. It has real limits: it cannot see Wi-Fi-style signals and has a much narrower view of the radio environment, so it will miss many fast-changing signals.

HackRF-class hardware gives FORSYTE a far wider view, and it is what site protection, GPS and GNSS interference awareness, automatic signal recognition and direction-finding workflows are built around.

Either way it works offline. FORSYTE does not need cloud access to detect, alert, log, or display activity on the map.

If you are working out what your situation needs, talk to us.

Free desktop SDR tools show you a waterfall on a laptop and leave you to interpret it. FORSYTE runs on a phone in the field, with no laptop, and turns raw radio into usable awareness:

• Persistence-based detection, so it flags real activity rather than every momentary spike.
• Plain-language and spoken voice alerts.
• A Signal Signature for every detection, so you can tell when the same transmitter comes back, and Automatic Signal Recognition to sort each detection into a signal family.
• A detection log and history, the FORSYTE Map, Drone ID Detection and TAK / ATAK export.

It all works fully offline. The value is the software layer that makes a receiver genuinely field-usable, not the radio.

FORSYTE RF is the SDR-based sensing app for Android. It lets you scan the frequencies you choose, detect persistent signal activity, and review alerts and signal history through a mobile interface built for fast field use.

Moving from a basic RTL-SDR receiver to HackRF-class hardware widens what FORSYTE can see, and unlocks:

• Wideband scanning, wider multi-signal detection, and the full Signal View.
• The GPS / GNSS Interference Monitor.
• Automatic Signal Recognition and the full Direction Finder.

Everything runs offline-first and field-ready either way.

FORSYTE is built for passive signal detection and situational awareness. Typical uses are lawful monitoring, testing, training, security and research - anywhere you need better visibility of the radio activity around you.

In most places, yes - FORSYTE is a passive, listen-only receiver. It never transmits, jams, spoofs, or decodes the content of communications, which is what most radio law restricts.

That said, the rules on which bands you may monitor, and what you may do with what you receive, vary by country - and you are responsible for using FORSYTE lawfully. It is built for lawful monitoring, testing, training, security and research; see the Acceptable Use section of the EULA.

RF stands for radio frequency - the part of the spectrum used for wireless communication and sensing. These radio waves travel at the speed of light and let devices send information without wires.

Everyday technologies use RF: radios, mobile phones, Wi-Fi, GPS, satellites, drones and two-way radios. Each one works within specific frequency bands so they can share the airwaves without interfering with each other.

An SDR (software-defined radio) is a radio combined with a small computer.

A traditional radio is built to listen to one kind of signal, such as FM or aircraft communications. An SDR is different: it captures raw radio and hands it to software, which can analyse it in many ways. Because software does the work, the same device can monitor very different kinds of radio activity just by changing that software.

FORSYTE uses compatible SDR hardware (such as HackRF-based devices) to receive signals across wide frequency ranges, then analyses that data in real time to flag unusual activity.

FORSYTE sweeps across the frequencies you choose and watches how the radio energy changes over time. The trick is not reacting to everything - the airwaves are noisy, and most of what you see is background. So FORSYTE:

• Learns what "normal" looks like where you are, and keeps updating it as conditions change.
• Ignores the constant background clutter, so it does not cry wolf.
• Waits for a signal to stay present before it calls it real, rather than firing on a momentary blip.

If something looks interesting in a wide sweep, FORSYTE can zoom in on a narrower slice of the spectrum to take a closer look and confirm it.

No. A signal-strength meter (sometimes called RSSI) only tells you how strong the radio energy is right now. FORSYTE starts there, but it also learns what the background normally looks like, ignores brief spikes, and waits for a signal to stick around before it calls it real. That is what cuts the false alarms.

More importantly, it captures a Signal Signature: a compact summary of the shape of each detection. That lets FORSYTE tell apart two transmitters sitting on the same frequency, and lets you use Find Similar to pull up past detections whose shape matches. Automatic Signal Recognition goes further and sorts each detection into a signal family - for example a drone's control link, its video downlink, or GPS interference. A strength meter can do neither. FORSYTE stays passive and listen-only throughout, and never reads message content.

There is no single fixed range. FORSYTE is a passive detector, so range depends on the signal source, your receiver and antenna, the frequency being monitored, and the local radio environment.

A powerful transmitter - an illegal signal booster, say, or a strong source of interference - might be picked up from several kilometres away, while a low-power “privacy plug” in a car might only be seen within a few hundred metres. Think of it like hearing: you can hear a jet engine from miles away, but a whisper only when it is right next to you.

The Interference Monitor uses HackRF-class hardware to watch the GPS L1 band in real time and compare current conditions against a learned baseline. Rather than reacting to a single spike, it looks for sustained abnormal power or spectrum behaviour before raising an alert.

It can also use your device's own GNSS health data - such as degraded satellite conditions or unusual position behaviour - for extra context. Alerts use a simple status workflow, so you can quickly see whether the environment looks normal, degraded, or actively interfered with.

Yes. Confirmed detections are saved as sessions, with the timing and history that go with them, and each one carries its Signal Signature. You can review activity over time and use Find Similar to pull up past detections that share the same signature. Everything stays on your device.

Automatic Signal Recognition sorts each detection into a signal family - for example a control link, a video downlink, or GPS / GNSS interference. It uses rule-based logic over the frequency band and the signal's spectral shape, then explains the result in plain language.

It works from a set of rules, not machine learning. It tells you the kind of signal; it does not read the content, and it does not name a specific device or drone model.

Every detection gets a Signal Signature - a short summary of what the signal's shape looks like. This lets FORSYTE tell apart two transmitters sitting on the same frequency, and lets you use Find Similar to pull up past detections whose shape matches.

It is a pattern, not a guaranteed identity: two devices set up the same way can produce the same signature. You can save signals you care about and have FORSYTE alert you when one of them appears again. What it will not do is match a signal against a catalogue of known third-party devices, and it never identifies a device make or model from radio alone.

Not by device or drone model - and that is deliberate. FORSYTE tells you the signal family (Automatic Signal Recognition) and gives each detection a Signal Signature to tell transmitters apart, but it will not tell you “that's a DJI Mavic.” Reliably naming a platform from RF energy alone is not something we will claim.

Drone ID / Remote ID is separate: that is an open, standards-based broadcast that many drones send out on purpose, so reading it is nothing like working out what a device is from its signal shape.

It sorts signals, but it never reads what they are carrying. Automatic Signal Recognition puts a detection into a signal family based on the band it is on and the shape of the signal (a set of rules, not machine learning). FORSYTE does not extract or read the contents of a transmission, and it does not identify the specific device behind it.

The Listen feature turns a signal into sound so you can hear what kind of thing it is - a voice, a data burst, a hiss. That is not the same as decoding a message.

You can turn a detected signal into sound you can actually hear, the way you would tune an analogue radio to work out whether something sounds like speech, data, or just noise. It works on an RTL-SDR receiver and above.

This is the raw sound of the radio signal, for identification only. It is not decoding the content of private communications, and FORSYTE does not transcribe, store or interpret speech.

Yes. The Direction Finder gives you a bearing: a line pointing from where you are standing toward the signal. It tells you which way the signal is coming from. On its own, it does not tell you how far away the source is.

One bearing narrows a signal down to a direction, not a place. If you move to a different spot and take a second bearing, the two lines cross - and where they cross is roughly where the signal is coming from. Take a third from somewhere else again and the estimate tightens. You end up with an approximate area rather than an exact dot on the map, and the further apart your positions are, the better that estimate gets.

How well this works depends on the transmitter, your receiver and antenna, and what is around you. Buildings, terrain and other radio activity can all bend or bounce a signal and throw a bearing off.

What you need: bearings work on an RTL-SDR Blog V4 receiver. The full Direction Finder needs HackRF-class hardware.

Being clear so there are no surprises. FORSYTE:

• Is passive and listen-only - it does not transmit, jam, spoof or interfere with anything.
• Does not decode the content of communications.
• Does not identify a device make/model or drone platform from RF.
• Is not a command-and-control or weapons system.
• Gives you a direction to a signal, not an exact location from a single reading.
• Has no fixed detection range - it depends on the transmitter, receiver, antenna and environment.

It also does not compare what it hears against a library of known third-party devices. You can save your own signals and be alerted when one of them turns up again, but FORSYTE does not ship with a catalogue of other people's signals to match against.

A compatible Android device is enough to start: the FORSYTE Map and Drone ID Detection run with no SDR at all.

To do spectrum sensing you add a supported radio receiver (SDR). An RTL-SDR receiver covers multi-signal detection and Signal View. HackRF-class hardware adds wideband scanning, Automatic Signal Recognition, the full Direction Finder and the GPS / GNSS Interference Monitor.

Use your own compatible hardware. We do not sell it.

FORSYTE is hardware-agnostic across two classes:

• An RTL-SDR receiver. The RTL-SDR Blog V4 is the reference model, and is required for RTL-SDR direction finding.
• A HackRF-class wideband receiver, roughly 1 MHz to 6 GHz.

Antenna choice depends on the bands you watch: a wideband whip to start, or directional antennas for direction finding.

You source the hardware yourself. FORSYTE is a software company and we do not sell or resell receivers.

Smartphones are not built to receive most of the RF used by drones, radios and other wireless systems. An SDR is a specialised receiver that can capture signals across a wide range of frequencies.

Connecting one to your Android device lets FORSYTE scan and analyse activity that would otherwise be invisible to the phone alone.

No. FORSYTE is software. You bring your own compatible SDR, which is the point: coverage grows with the receivers and the people an organisation already has, rather than with a procurement budget.

If you build radios yourself and want FORSYTE running on them, that is a conversation we do want to have.

Yes, FORSYTE is offline-first. Signal detection and the interface run on-device. You only need internet for licence activation, updates and support.

The FORSYTE Map is an awareness map that plots your RF detections and Drone ID / Remote ID contacts geographically, so you can see where activity is happening around you in real time. It is there from the free app onwards, with no SDR required.

It is for situational awareness only - not a command-and-control surface, a tasking tool, or a multi-node tracking network. It simply shows the detections from your own device, on a map you control.

Yes, where available. Drone ID Detection decodes the standards-based Remote ID broadcasts that many drones transmit, so you can see nearby Remote ID contacts on the FORSYTE Map.

Basic Drone ID Detection is part of the free app. Coverage depends on what each drone broadcasts and on local regulations, so it varies by region and device - it is provided on a “where available” basis, and is separate from the RF scanning engine.

Yes. FORSYTE works with the TAK ecosystem (ATAK / WinTAK) to boost shared situational awareness. It can automatically export live RF detections and GPS interference alerts as Cursor-on-Target (CoT) events - the standard message format TAK apps use to share map contacts. TAK / ATAK export needs a connected receiver.

• Connection: CoT output over UDP to a host and port you set.
• Alert types: map markers (a pin at your location when something is detected), chat messages, or both.
• Result: teammates see your real-time detections on their own TAK maps as they happen.

FORSYTE is an awareness and export tool - it is not a command-and-control system.

Yes. FORSYTE is built to talk to you, not just show data on a screen. When you are moving, driving, or your hands and eyes are busy, you cannot watch a display - so FORSYTE can speak an alert out loud when something important happens, and you can keep your attention on what you are doing.

FORSYTE is offline-first and privacy-conscious:

• RF processing happens on your device. Your scan data, detections and log stay on the device - they are not uploaded to us.
• The app needs internet only for licence activation, updates and support.
• Like most apps, it may send anonymous crash and basic usage analytics through Google Play, which you can control in your device settings.
• Licences are device-bound. We do not collect your detections or your location.

This website is separate: it uses optional, consent-based analytics only if you accept. See the Privacy Policy and Cookie Notice.

Download the free app first: it gives you the FORSYTE Map and Drone ID Detection on any Android phone, with no extra hardware and nothing to buy.

Beyond that, get in touch and we will work out what you actually need. Deployments differ enough that a conversation gets you to the right place faster than a menu does.

Licences are issued per device and are non-transferable by default, and there is no self-serve device reset. If you need to move a licence to a new device, or you hit an activation problem, contact support and we will help.

Software licences are generally non-refundable once a key has been issued and activated, subject to your statutory rights. The exact terms are in the Sales Terms.

Yes. Existing licences remain valid and keep working exactly as before. If you hit an activation problem, contact support and we will sort it out.