---

Read this first — what Nyx can and cannot see

This is the part most "hidden camera detector" apps quietly skip, and it is the whole reason to trust or distrust a reading. Nyx is honest about it on the device and here.

Nyx finds IR emitters, not cameras. A camera only shows up while it is actively lighting the room with infrared. That is exactly what a night-vision camera does in the dark — so Nyx is at its best doing a lights-off sweep of a dark room, which is also when a covert camera is most likely emitting.

There is a second catch, and it comes from the Flipper's hardware.

The two modes, and why there are two

	Onboard (no extra hardware)	Probe (+ ~$1 phototransistor)
Sensor	Built-in TSOP-75338 IR receiver	IR phototransistor on a GPIO ADC pin
Sees steady DC illuminators	❌ No	✅ Yes
Sees pulsed / modulated IR	✅ Yes	✅ Yes
Finds a typical night-vision camera	⚠️ Only if it pulses its LEDs	✅ Yes
Setup	Just run it	Wire a probe (2 min, see below)

The Flipper's onboard IR receiver is a demodulating part: it has a band-pass filter centred on 38 kHz and automatic gain control, built to pull TV-remote codes out of a sunlit room. That filter throws away steady light. A covert camera whose IR illuminator runs at constant DC current — very common — is invisible to the onboard receiver no matter how bright it is. A clean 0 in onboard mode does not mean the room is clean. Onboard mode still catches anything pulsed: remotes, IR beacons and link ports, PIR sensor floodlights, and illuminators driven by PWM.

To actually catch a steady illuminator you need a sensor without that filter. That is what Probe mode is: a bare IR phototransistor on an ADC pin, which reads DC light directly and can even tell a steady illuminator apart from a mains-flickering lamp. It costs about a dollar and two minutes. If you are serious about a sweep, wire the probe.

Auto mode uses the probe if one is plugged in, otherwise the onboard receiver, and the header always tells you which one is live.

---

Using it

1. Sweep — the meter, built around an eye that watches back. Kill the room lights, then pan the Flipper slowly across walls, smoke detectors, alarm clocks, vents, mirrors, and anything with a pinhole. The eye's ring fills and its pupil dilates as the signal rises, a tick marks your best reading so far, and the big trend arrow (▲ getting warmer / ▼ colder) points you in. When it locks on, glare spikes spin around the iris and the geiger clicks and LED speed up as you close in.
2. Probe Setup — how to wire the phototransistor, plus a live check so you can prove the probe works (aim a TV remote at it and watch the needle jump) before you trust a clean sweep.
3. Settings — mode, sensitivity, probe pin, and sound/vibro/LED. Your choices are saved and restored on the next launch.
4. About — the same honesty notes, on the device.

Reading the source label

• STEADY — flat DC light. This is the night-vision illuminator signature. Probe mode only.
• FLICKER — ~100/120 Hz ripple. Riding the mains, so almost always a lamp, a heater, or a screen — not a camera.
• PULSED — faster modulation. A remote, a beacon, or a PWM-driven illuminator.

Keys

Key	Action
OK	Zero the peak-hold and hit count
Hold OK	Re-null the ambient baseline (probe mode) — do this after you walk into a new room
← / →	Flip between the wiring diagram and the live check on Probe Setup
Back	Leave the sweep / return to the menu

---

Building the probe (optional, but it's the real tool)

You need one part: an IR phototransistor — the dark-epoxy kind with a daylight filter, sold for pairing with 940 nm IR LEDs — and one 10 kΩ resistor. It wires as an emitter-follower: more IR in, more volts out.

        3V3  (pin 9)
         │
        ┌┴┐   IR phototransistor
    IR →│ │   (collector to 3V3)
        └┬┘
         ├───────────►  ADC pin — PC0 (pin 16) by default
        ┌┴┐
        │ │  10 kΩ
        └┬┘
         │
        GND  (pin 18)

Phototransistor lead	Wire to	Flipper pin
Collector	3V3	pin 9
Emitter	ADC in + one end of 10 kΩ	PC0, pin 16
(10 kΩ other end)	GND	pin 18

You can pick any ADC-capable pin (PC0, PC1, PC3, PA4, PA6, PA7) under Settings → Probe pin; the Probe Setup screen always shows the pin it expects by its silkscreened number. Nyx detects the probe automatically by sensing the load on the pin.

Then open Probe Setup → → and press a key on any TV remote pointed at the phototransistor. If the reading jumps, you're good.

---

Limits — please read

• Nyx finds emitters, not cameras. A camera sitting in a lit room (no IR needed) or switched off emits nothing, and Nyx will not see it. Do a lights-off sweep.
• IR reflects. A strong reading can be a bounce off a wall or mirror rather than the source. Move around; triangulate on the peak.
• The world is full of IR. Sunlight, incandescent and halogen bulbs, remote controls, and PIR sensors all emit it. Treat a hit as a reason to look closely, not as proof. Confirm with your eyes — most phone cameras (front cameras especially) see 850 nm IR as a faint purple glow, so cross-check by looking at the suspected source through a phone.
• Nyx is a triage tool to point you at things worth inspecting. It is not a guarantee, and no RF/IR gadget is.

---

Install

From a release (easiest)

Download nyx.fap from the latest release and drop it in apps/Infrared/ on your Flipper's SD card (qFlipper, or the mobile app). It shows up under Apps → Infrared → Nyx. Works on stock firmware — no custom firmware required.

From source

python3 -m pip install --upgrade ufbt
ufbt update            # pull the SDK (release channel)
git clone https://github.com/at0m-b0mb/Nyx-FlipperZero.git
cd Nyx-FlipperZero
ufbt                   # builds dist/nyx.fap
ufbt launch            # build + install to a connected Flipper

Regenerate the art after editing the generators:

python3 tools_gen_icons.py
python3 tools_gen_banner.py
python3 tools_gen_mockups.py

---

How it works

• helpers/ir_sense.c — the dual-path engine, on a worker thread.
  • Onboard: furi_hal_infrared_async_rx_* with a capture ISR that counts output edges per window. Edge-rate is the activity metric; we never decode, because we don't care what is transmitted, only that something is.
  • Probe: furi_hal_adc_* sampling a dense 32 ms burst each window, reduced to mean level (nulled against the ambient baseline captured at arm time), peak-to-peak ripple, and a mean-crossing ripple frequency that separates a steady illuminator from mains flicker. Oversampling is deliberately off so the ripple survives.
  • The probe pin list is built from the SDK's own gpio_pins[] ADC table, so it can't drift from the HAL.
• views/sweep_view.c — the locating instrument: an eye whose ring fills with the live level, whose pupil dilates as you close in, with a peak tick, a source label, a get-warmer trend arrow, and an inverted alarm strip when an emitter is locked on. In onboard mode it keeps admitting, in the idle hint line, that it can only see pulsed IR.
• views/probe_view.c — the wiring schematic and the live probe check.
• views/splash_view.c — the boot intro: a Nyx eye opening through IR wave-rings (any key skips it).
• helpers/nyx_store.c — settings persistence via the firmware's saved_struct, so mode / sensitivity / probe pin survive a relaunch.
• scenes/ — splash / start / sweep / probe / settings / about, wired with the standard Flipper scene-manager X-macro.

Listen-only. Nyx never transmits IR.

---

Credits & license

Built by at0m-b0mb. MIT licensed — see LICENSE.

Part of a family of Flipper counter-surveillance tools: Specter (NFC reader sweep), Argus (Wi-Fi deauth detector), GhostTag (BLE tracker hunter).

Use Nyx to protect your own privacy and only in spaces you are entitled to sweep. You are responsible for complying with local law.